INTRODUCTION
⌅Tamarix L. (Tamaricaceae) includes between 60 and 90 species (Baum 1966Baum B.R. 1966. Monographic Revision of the genus Tamarix. Final research report for the USDA. Department of Botany. Hebrew University, Jerusalem., 1978Baum B.R. 1978. The genus Tamarix. Israel Academy of Sciences and Humanities, Jerusalem. ; Qaiser 1981Qaiser M. 1981. The genus Tamarix Linn. (Tamaricaceae) in Pakistan. Pakistan Journal of Botany 13: 107-158.; Zohary 1972Zohary M. 1972. Tamarix L. In Zohary M. (ed.), Flora palaestina vol. 2: 350-362. Israel Academy of Sciences and Humanities, Jerusalem. [Reprint 1987].; Yang & Gaskin 2007Yang Q. & Gaskin J.F. 2007. Tamarix. In Zhengyi W. & Raven P.H. (eds.), Flora of China 13: 59-65. Science Press, Beijin, & Missouri Botanical Garden Press, St. Louis.), which are naturally distributed in Eurasia and Africa. They tend to inhabit arid, desertic or sub-desertic areas, under Mediterranean, Temperate or Subtropical climates (Zohary 1972Zohary M. 1972. Tamarix L. In Zohary M. (ed.), Flora palaestina vol. 2: 350-362. Israel Academy of Sciences and Humanities, Jerusalem. [Reprint 1987].). The taxonomy of the genus has repeatedly been considered to be complex by most of the authors who dealt with that group (Bunge 1852Bunge A. 1852. Tentamen Generis Tamaricum Species Accuratius Definiendi. J.C. Schuenmanni & C. Mattieseni, Dorpati.; Baum 1966Baum B.R. 1966. Monographic Revision of the genus Tamarix. Final research report for the USDA. Department of Botany. Hebrew University, Jerusalem., 1978Baum B.R. 1978. The genus Tamarix. Israel Academy of Sciences and Humanities, Jerusalem. ; Zohary 1972Zohary M. 1972. Tamarix L. In Zohary M. (ed.), Flora palaestina vol. 2: 350-362. Israel Academy of Sciences and Humanities, Jerusalem. [Reprint 1987].). Most of the characters used for species discrimination are, to certain degree, variable within a species or even in a single specimen, and only the use of a combination of characters allows reliable identifications (Villar & al. 2012Villar J.L., Alonso M.Á., Juan A. & Crespo M.B. 2012. Does Tamarix dalmatica (Tamaricaceae) occur in Spain? Anales del Jardín Botánico de Madrid 69: 253-258. ). These morphological complications have resulted in the publication of hundreds of names at species and lower ranks, which implies that some of the currently accepted species include many synonyms. As a result, some species have been reported to territories where they are actually absent (Villar & al. 2012Villar J.L., Alonso M.Á., Juan A. & Crespo M.B. 2012. Does Tamarix dalmatica (Tamaricaceae) occur in Spain? Anales del Jardín Botánico de Madrid 69: 253-258. ) or else overlooked for years in territories in which they are pretty common (Villar & al. 2014Villar J.L., Alonso M.Á., Juan A., Gaskin J.F., & Crespo M.B. 2014. Proposal to conserve the name Tamarix ramosissima against T. pentandra (Tamaricaceae). Taxon 63: 1140-1141. ).
The possibility of interspecific hybridization has also been dealt with in the past (Gorschkova 1949Gorschkova S.G. 1949. Tamaricaceae. In Komarov V.L. (ed.), Flora URSS vol. 15: 290-327. Izdatelstvo Akademii Nauk SSSR, Moscow-Leningrad.; Baum 1966Baum B.R. 1966. Monographic Revision of the genus Tamarix. Final research report for the USDA. Department of Botany. Hebrew University, Jerusalem., 1978Baum B.R. 1978. The genus Tamarix. Israel Academy of Sciences and Humanities, Jerusalem. ). More recently, it has become clear that hybridization occurs (Gaskin & Schaal 2003Gaskin J.F. & Schaal B. 2003. Hybrid Tamarix widespread in U.S. invasion and undetected in native Asian range. Proceedings of the National Academy of Sciences 99: 11256-11259.), that it can happen between species morphologically very distant (Gaskin & Shafroth 2005Gaskin J.F. & Shafroth P.B. 2005. Hybridization of T. ramosissima and T. chinensis (saltcedars) with T. aphylla (athel) (Tamaricaceae) in the Southwestern USA determined from DNA sequence data. Madroño 52: 1-10.; Mayonde & al. 2015Mayonde S.G., Cron G.V., Gaskin J.F. & Byrne M.J. 2015. Evidence of Tamarix hybrids in South Africa, as inferred by nuclear ITS and plastid trnS-trnG DNA sequences. South African Journal of Botany 96: 122-131.) and that hybridization processes must have played a key role in the evolution of this genus (Villar & al. 2019Villar J.L., Alonso M.Á., Juan A., Gaskin J. & Crespo M.B. 2019. Out of the Middle East: new phylogenetic insights in the genus Tamarix (Tamaricaceae). Journal of Systematics and Evolution 57: 488-507.). However, up to now, no hybrid has been officially described under the rules of the International Code of Nomenclature for Algae, Fungi and Plants (Turland & al. 2018Turland N.J., Wiersema J.H., Barrie F.R., Greuter W., Hawksworth D.L., Herendeen P.S., Knapp S., Kusber W.-H., Li D.-Z., Marhold K., May T.W., McNeill J., Monro A.M., Prado J., Price M.J. & Smith G.F. 2018. International Code of Nomenclature for algae, fungi, and plants (Shenzhen Code) adopted by the Nineteenth International Botanical Congress Shenzhen, China, July 2017. [Regnum Vegetabile 159]. Koeltz Botanical Books, Glashütten.).
Prior to the publication of Species plantarum (Linnaeus 1753Linnaeus C. 1753. Species plantarum vol. 1. Laurentii Salvii, Holmiae [Stockholm].), we can find some direct references to Tamarix in the Iberian Peninsula in the works of authors such as Mattioli (1562: 127)Mattioli P.A. 1562. Comentarii denuo aucti, in libros sex Pedacii Dioscoridis Anzarabei de medica materia. Gabrielem Coterium, Lugduini (Lyon)., Clusius (1576: 106)Clusius C. 1576. Rariorum aliquot stirpium per hispanias observarum historia. Christophori Platini, Antwerpen (Amberes), 104-107., Dalechamps (1586: 179)Dalechamps S.J. 1586. Historia generalis plantarum. Pars prima. Leiden., Bauhin & Cherler (1650: 350-351)Bauhin J. & Cherler, J.H. 1650. Historia Plantarum Universalis vol. 1. Ebroduni [Yverdon]. or Linnaeus himself (1737)Linnaeus C. 1737. Hortus Cliffortianus. Amstelaedami [Amsterdam].. In the late 19th Century, the reference work for the Iberian botany (Willkomm 1880Willkomm H.M. 1880. Tamariscinae St. Hil. In Willkomm H.M. & Lange J.M.C. (eds.), Prodromus florae hispanicae vol. 3: 596-598. Sumtibus E. Schweizerbart, Stuttgartiae.) included only 3 species: Tamarix gallica L., T. anglica Webb. (currently synonymized to T. gallica) and T. africana Poir. It did not include T. hispanica Boiss. (Boissier 1856Boissier E. 1856. Diagnoses Plantarum Orientalium Novarum ser. 2, 3(2): 56-59. B. Herrmann, Leipzig.), the only species described with material from the Iberian Peninsula to that moment. The early 20th Century sought a great increase of new names, all based on the prolific work of Pau, Sennen and their respective collaborators (Pau 1906Pau C. 1906. Synopsis formarum novarum hispanicarum cum synonimin nonnullis accedentibus. Bulletin de l’Académie Internationale de Géographie Botanique 206: 73-77. , 1918Pau C. 1918. Una ligera visita botánica a Tous. Butlletí de la Institució Catalana d’Història Natural 18: 158-161., 1922Pau C. 1922. Nueva contribución al estudio de la flora de Granada. Memòries del Museu de Ciències Naturals de Barcelona. Sèrie Botànica 1(1): 74. ; Pau & Huguet del Villar 1927Pau C. & Huget del Villar E. 1927. Novae Tamaricis in Hispania centrali. Broteria 23: 101-113.; Sennen 1928Sennen F. 1928. Plantes d’Espagne, par le Fr. Sennen-Diagnoses et comentaires. Boletín de la Sociedad Ibérica de Ciencias Naturales 27: 66-67., 1932Sennen F. 1932. Brèves diagnoses des formes nouvelles parues dans nos exsiccata “Plantes d’Espagne-F. Sennen”. Butlletí de la Institució Catalana d’Història Natural 32: 90., 1936Sennen F. 1936. Diagnoses des nouveautés parues dans les exsiccata Plantes d’Espagne et du Maroc de 1928 a 1935. Ed. Anglada, Vic.). However, none of the names described by the later authors is currently accepted (see Baum 1978Baum B.R. 1978. The genus Tamarix. Israel Academy of Sciences and Humanities, Jerusalem. ; Cirujano 1993Cirujano S. 1993. Tamarix L. In Castroviejo S., Aedo C., Cirujano S., Laínz M., Monserrat P., Morales R., Muñoz Garmendia F., Navarro C., Paiva J. & Soriano C. (eds.), Flora iberica vol. 3: 437-443. Real Jardín Botánico, CSIC, Madrid.; Villar & al. 2021Villar J.L., Alonso M.Á. & Crespo M.B. 2021. Remarks on the types of Tamarix names (Tamaricaceae) described from the Iberian Peninsula. Phytotaxa 484: 281-290. ; Villar & Alonso 2016Villar J.L. & Alonso M.Á. 2016. Tamarix mascatensis. In Raab-Straube E. von & Raus T. (eds.), Euto+Med Checklist Notulae 6. Willdenowia 46: 423-442.). The following great contribution to the knowledge of the Iberian Tamarix was the monograph by Baum (1966)Baum B.R. 1966. Monographic Revision of the genus Tamarix. Final research report for the USDA. Department of Botany. Hebrew University, Jerusalem., which reached major diffusion under a later version (Baum 1978Baum B.R. 1978. The genus Tamarix. Israel Academy of Sciences and Humanities, Jerusalem. ) including only minor changes. Baum’s treatment (1966Baum B.R. 1966. Monographic Revision of the genus Tamarix. Final research report for the USDA. Department of Botany. Hebrew University, Jerusalem., 1978Baum B.R. 1978. The genus Tamarix. Israel Academy of Sciences and Humanities, Jerusalem. ) accepted five species for the Iberian Peninsula, with a number of synonyms for each of them: T. africana Poir., T. boveana Bunge, T. canariensis Willd., T. gallica L., and T. parviflora DC. The four species were considered native, except for T. parviflora whose native status remains doubtful. We have not found references of specimens that can be assigned to T. parviflora prior to the publication of T. lucronensis Sennen & Elías by Sennen (1928)Sennen F. 1928. Plantes d’Espagne, par le Fr. Sennen-Diagnoses et comentaires. Boletín de la Sociedad Ibérica de Ciencias Naturales 27: 66-67.. The same number of species was reported in Flora europaea, whose Tamarix treatment was indeed conducted by Baum (1968)Baum B.R. 1968. Tamarix L. In Tutin T.G., Heywood V.H., Burges N.A., Moore D.M., Valentine D.H., Walters S.M. & Webb D.A. (eds.), Flora Europaea 2: 292-294. Cambridge University Press, Cambridge. [Reprint 1990].. Apart from the inclusion of T. boveana and T. parviflora, Baum (1978)Baum B.R. 1978. The genus Tamarix. Israel Academy of Sciences and Humanities, Jerusalem. restricted T. gallica to the southwestern side of Europe, and expanded the distribution of T. canariensis (previously restricted to the Canary Islands) to northwestern Africa, the Iberian Peninsula, the southern Mediterranean coast of France, Corsica, and Sardinia. These changes were based on morphological aspects that were later found to be inconsistent and thus, on the basis of morphological and phylogenetic information (Villar & al. 2019Villar J.L., Alonso M.Á., Juan A., Gaskin J. & Crespo M.B. 2019. Out of the Middle East: new phylogenetic insights in the genus Tamarix (Tamaricaceae). Journal of Systematics and Evolution 57: 488-507.), the presence of T. canariensis in the Iberian Peninsula was discarded, and the species is currently regarded as a Macaronesian endemism.
The next step on the knowledge of the Iberian species of Tamarix was taken by Cirujano (1993)Cirujano S. 1993. Tamarix L. In Castroviejo S., Aedo C., Cirujano S., Laínz M., Monserrat P., Morales R., Muñoz Garmendia F., Navarro C., Paiva J. & Soriano C. (eds.), Flora iberica vol. 3: 437-443. Real Jardín Botánico, CSIC, Madrid. in his genus treatment for Flora iberica. Cirujano (1993)Cirujano S. 1993. Tamarix L. In Castroviejo S., Aedo C., Cirujano S., Laínz M., Monserrat P., Morales R., Muñoz Garmendia F., Navarro C., Paiva J. & Soriano C. (eds.), Flora iberica vol. 3: 437-443. Real Jardín Botánico, CSIC, Madrid. maintained the five species proposed by Baum (1978)Baum B.R. 1978. The genus Tamarix. Israel Academy of Sciences and Humanities, Jerusalem. and added four more: T. ramosissima Ledeb., and T. chinensis Lour., as introduced; T. mascatensis Bunge, first reported by De Martis & al. (1985De Martis B., Loi M.C. & Polo M.B. 1985. Tamarix mascatensis Bge. (Tamaricaceae) in Portogallo, nuova per la flora d’Europa. Boletim da Sociedade Broteriana 58: 215-217.); and T. dalmatica Baum. The presence of T. dalmatica and T. mascatensis in the Iberian Peninsula was later discussed and discarded (Villar & al. 2012Villar J.L., Alonso M.Á., Juan A. & Crespo M.B. 2012. Does Tamarix dalmatica (Tamaricaceae) occur in Spain? Anales del Jardín Botánico de Madrid 69: 253-258. ; Villar & Alonso 2016Villar J.L. & Alonso M.Á. 2016. Tamarix mascatensis. In Raab-Straube E. von & Raus T. (eds.), Euto+Med Checklist Notulae 6. Willdenowia 46: 423-442.). More recently, new names (T. arborea (Ehrenb.) Bunge, T. arborea var. subvellutina Boiss. and T. meyeri Boiss.) have been reported in the Iberian Peninsula (Gil & al. 1996Gil Ll., Tébar F.J. & Boi M. 1996. Notes florístiques de les illes Balears (VIII). Bolletí de la Societat d’Història Natural de les Balears 39: 117-128.; Gargano & al. 2009Gargano M.L., Mandracchia G & Venturella G. 2009. Tamarix arborea var. subvelutina (Tamaricaceae), new from Spain. Lagascalia 29: 320-321.; Venturella & al. 2012Venturella G., Gargano M.L. & Mandracchia G. 2012. First record of Tamarix meyeri (Tamaricaceae) for western Europe. Plant Biosystems 146: 484-489.). Moreover, the last contribution from Gargano & al. (2018)Gargano M.L., Mandracchia G., Venturella G. & Calvo R. 2018. A revision of Tamarix specimens (Tamaricaceae) kept in the BCN herbarium of Barcelona (Spain). Flora Mediterranea 28: 393-397. increased the species number up to 14. Therefore, Gargano & al. (2018)Gargano M.L., Mandracchia G., Venturella G. & Calvo R. 2018. A revision of Tamarix specimens (Tamaricaceae) kept in the BCN herbarium of Barcelona (Spain). Flora Mediterranea 28: 393-397. included names never mentioned before in the studied territory, such as T. octandra Bunge, T. rosea Bunge, T. tetragyna Ehrenb., and T. mannifera Ehrenb. ex Bunge. These recent records will be discussed further below, since they are here considered to be doubtful or mere misidentifications. The last addition to the Iberian Tamarix account is T. aphylla (L.) H.Karst. (Terrones & al. 2016Terrones A., Moreno J., Agulló J.C., Villar J.L., Vicente A., Alonso M.Á. & Juan A. 2016. Influence of salinity and storage on germination of Tamarix taxa with contrasted ecological requirements. Journal of Arid Environments 135: 17-21.), which we have been collecting from cultivated specimens in different localities since 2011.
The aim of this study is to synthesize the current knowledge on the genus Tamarix and to update the account for the Iberian species. We used both morphological comparisons and available phylogenetic information (Villar & al. 2019Villar J.L., Alonso M.Á., Juan A., Gaskin J. & Crespo M.B. 2019. Out of the Middle East: new phylogenetic insights in the genus Tamarix (Tamaricaceae). Journal of Systematics and Evolution 57: 488-507.). Our approach to the classification of different species does not strictly follow the common reference of Baum (1978)Baum B.R. 1978. The genus Tamarix. Israel Academy of Sciences and Humanities, Jerusalem. , given that we accept a wider plasticity in characters previously considered as highly diagnostic, such as the staminal disk or the presence of papillae on the rachis of the racemes (see Villar & al. 2012Villar J.L., Alonso M.Á., Juan A. & Crespo M.B. 2012. Does Tamarix dalmatica (Tamaricaceae) occur in Spain? Anales del Jardín Botánico de Madrid 69: 253-258. , 2019Villar J.L., Alonso M.Á., Juan A., Gaskin J. & Crespo M.B. 2019. Out of the Middle East: new phylogenetic insights in the genus Tamarix (Tamaricaceae). Journal of Systematics and Evolution 57: 488-507.). Therefore, an identification key to the Iberian Tamarix species is provided, and a new hybrid between T. boveana and T. gallica is described as Tamarix × verae.
MATERIALS AND METHODS
⌅Since 2009, about 3000 specimens have been studied at several European and American herbaria: ABH, B, BC, G, K, MA, MEX, MO, MPU, P, PR, PRC, and W (codes according to Thiers 2021+Thiers B. 2021+. Index Herbariorum: A global directory of public herbal and associated staff. New York Botanical Garden’s Virtual Herbarium, New York. Website: http://sweetgum.nybg.org/science/ih/ [accessed: 1 Sep. 2022].), as well as from herbarium loans (BCN, JAEN, UIB, VAL), in order to get a global idea of the genus. Moreover, new collections were made in Morocco, Algeria, Italy, Greece, Montenegro, Albania, Croatia, France and different parts of the Iberian Peninsula; specimens are kept at the herbarium of the University of Alicante (ABH).
The study of specimens was mainly conducted through observation of leaf material and dissection of flowers under a binocular microscope. Racemes or flowers were re-hydrated before study in order to observe all floral parts without destroying them. The identifications were based in the information provided by various monographs (Bunge 1852Bunge A. 1852. Tentamen Generis Tamaricum Species Accuratius Definiendi. J.C. Schuenmanni & C. Mattieseni, Dorpati.; Niedenzu 1925Niedenzu F. 1925. Tamaricaceae. In Engler A. & Prantl K. (eds.), Die natürlichen Pflanzenfamilien vol. 21: 282-289. W. Engelmann, Berlin.; Baum 1978Baum B.R. 1978. The genus Tamarix. Israel Academy of Sciences and Humanities, Jerusalem. ) and local treatments (Cirujano 1993Cirujano S. 1993. Tamarix L. In Castroviejo S., Aedo C., Cirujano S., Laínz M., Monserrat P., Morales R., Muñoz Garmendia F., Navarro C., Paiva J. & Soriano C. (eds.), Flora iberica vol. 3: 437-443. Real Jardín Botánico, CSIC, Madrid.; Salazar & Quesada 2011Salazar C. & Quesada J. 2011. Tamarix L. In Blanca G., Cabezudo B., Cueto M., Morales Torres C. & Salazar C. (eds.), Flora vascular de Andalucía Oriental ed. 2, vol. 2: 590-593. Universities of Almería, Granada, Jaén and Málaga, Granada.), as well as in the detailed study of type materials and other herbarium specimens.
The list of studied specimens (Appendix 1) is shortlisted to a selection of Iberian material, type material and collections relevant for being close to type localities or for other reasons. Moreover, some vouchers from species not accepted here as present in the Iberian Peninsula, are also included. Materials already listed in previous publications are not included on the list but referenced to their respective publication. Morphological descriptions are based on those specimens.
Distribution maps showing the species occurrences by province are provided for all accepted species occurring in the Iberian Peninsula and the Balearic Islands. Those are based on the studied materials and completed with the information in Flora iberica (Cirujano 1993Cirujano S. 1993. Tamarix L. In Castroviejo S., Aedo C., Cirujano S., Laínz M., Monserrat P., Morales R., Muñoz Garmendia F., Navarro C., Paiva J. & Soriano C. (eds.), Flora iberica vol. 3: 437-443. Real Jardín Botánico, CSIC, Madrid.). It is likely that the natural distribution of the studied species is not completely covered by the revised herbarium materials and, therefore, some distributions are probably wider than those reflected on the maps.
Accepted species are listed alphabetically. Synonyms follow each accepted species entry, including only those names that have been described on Iberian or Balearic materials or that have been used to name specimens from de Iberian Peninsula.
Taxonomic procedures conform to the International Code of Nomenclature for Algae, Fungi and Plants (Turland & al. 2018Turland N.J., Wiersema J.H., Barrie F.R., Greuter W., Hawksworth D.L., Herendeen P.S., Knapp S., Kusber W.-H., Li D.-Z., Marhold K., May T.W., McNeill J., Monro A.M., Prado J., Price M.J. & Smith G.F. 2018. International Code of Nomenclature for algae, fungi, and plants (Shenzhen Code) adopted by the Nineteenth International Botanical Congress Shenzhen, China, July 2017. [Regnum Vegetabile 159]. Koeltz Botanical Books, Glashütten.). Citations of names follow IPNI (2022+)IPNI. 2022+. International Plant Names Index. The Royal Botanic Gardens, Kew, Harvard University Herbaria & Librasies and Australian National Botanic Gardens. Website: http://www.ipni.org [accessed 1 Sep. 2022]..
RESULTS
⌅Key to the Iberian and Balearic species of Tamarix
⌅-
1. Leaves vaginate (Fig. 1a) … T. aphylla
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- Leaves scale-like, sometimes auriculate at base but never clasping or embracing the twigs around … 2
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2. Flowers mostly tetramerous … 3
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Flowers mostly pentamerous … 4
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• Racemes 4-5 mm wide; bracts 1-1.8(2) mm, not reaching the calyx tip … T. parviflora
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- Racemes 7-15 mm wide; bracts 3-8 mm long, reaching the calyx upper level or clearly surpassing it (Fig. 1e) … T. boveana
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4. Blackish branches; racemes 5-8 mm wide, with a short peduncle densely covered by broad scarious bracts (Fig. 1g); petals 2-3 mm; sepals (0.8)1-1.5(2.5) mm long … T. africana
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-Branches brown to reddish; racemes 3-5 mm wide; petals 1-2 mm; sepals 0.5-1 mm long … 5
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5. Staminal filaments inserted above the disc lobes, or rising from the disc lobes; petals deciduous, flat or slightly retrorse at maturity … T. gallica
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- Staminal filaments inserted between the disc lobes; petals persistent and concave, forming a cup shaped flower (Fig. 1i) … T. gr. ramosissima
Taxonomic treatment
⌅The examination of the studied specimens has resulted in the shortage from 14 species (Gargano & al. 2018Gargano M.L., Mandracchia G., Venturella G. & Calvo R. 2018. A revision of Tamarix specimens (Tamaricaceae) kept in the BCN herbarium of Barcelona (Spain). Flora Mediterranea 28: 393-397. ) to only seven of which three are native (T. africana, T. boveana, and T. gallica), one was probably introduced in the late 19th or the early 20th Century (T. parviflora), and three are relatively recent introductions (T. aphylla, T. ramosissima, and T. chinensis).
Tamarix africana Poir., Voy. Barbarie 2: 139 (1789). Type: Algeria. “Côte de barbarie. Poiret” (lectotype designated as “holotype” by Baum (1966: 97)Baum B.R. 1966. Monographic Revision of the genus Tamarix. Final research report for the USDA. Department of Botany. Hebrew University, Jerusalem.: P-LA 00287249!; isolectotype: P 00166702!).
Tamarix hispanica Boiss., Diagn. Pl. Orient. ser. 2, 2: 56 (1856). Type: Spain. Jaén. Puerta, Guadalmena, 1849, A. Blanco 340 (lectotype designated by Villar & al. (2021: 285)Villar J.L., Alonso M.Á. & Crespo M.B. 2021. Remarks on the types of Tamarix names (Tamaricaceae) described from the Iberian Peninsula. Phytotaxa 484: 281-290. : G 00359317!; isolectotypes: K 000641862 [photo!], P 04957866!).
Tamarix segobricensis Pau, Butl. Inst. Catalana Hist. Nat. 18: 160 (1918)Pau C. 1918. Una ligera visita botánica a Tous. Butlletí de la Institució Catalana d’Història Natural 18: 158-161.. Type: Spain. Castellón, Segorbe, May 1918, C. Pau s.n. (lectotype designated by Villar & al. (2021: 287)Villar J.L., Alonso M.Á. & Crespo M.B. 2021. Remarks on the types of Tamarix names (Tamaricaceae) described from the Iberian Peninsula. Phytotaxa 484: 281-290. : MA 79030!).
Tamarix calarantha Pau, Mem. Mus. Ci. Nat. Barcelona, Ser. Bot. 1: 43 (1922)Pau C. 1922. Nueva contribución al estudio de la flora de Granada. Memòries del Museu de Ciències Naturals de Barcelona. Sèrie Botànica 1(1): 74. . Type: Spain. Málaga, de Torre del Mar a La Cala, 3 Jun. 1919, E. Gros s.n. (lectotype designated by Villar & al. (2021: 282)Villar J.L., Alonso M.Á. & Crespo M.B. 2021. Remarks on the types of Tamarix names (Tamaricaceae) described from the Iberian Peninsula. Phytotaxa 484: 281-290. : MA 78981!; isolectotype: BC 22345 [photo!]).
Tamarix malacitana Pau, Mem. Mus. Ci. Nat. Barcelona, Ser. Bot. 1: 43 (1922)Pau C. 1922. Nueva contribución al estudio de la flora de Granada. Memòries del Museu de Ciències Naturals de Barcelona. Sèrie Botànica 1(1): 74. . Type: Spain. Granada, La Herradura, 29 Apr. 1919, E. Gros s.n. (neotype designated by Villar & al. (2021: 286)Villar J.L., Alonso M.Á. & Crespo M.B. 2021. Remarks on the types of Tamarix names (Tamaricaceae) described from the Iberian Peninsula. Phytotaxa 484: 281-290. : BC 22338 [photo!]).
Tamarix longebracteolata Sennen, Pl. Espagne 1926 n.º 5735 (1926). Type: Spain. Tarragona, Cambrils, large lit desséché du torrent de Riudoms, 1 Mar., fr. Sennen s.n. (lectotype designated by Villar & al. (2021: 286)Villar J.L., Alonso M.Á. & Crespo M.B. 2021. Remarks on the types of Tamarix names (Tamaricaceae) described from the Iberian Peninsula. Phytotaxa 484: 281-290. : MA 79040!; isolectotype: BCN 58969!, G 6990/1338!, G 6990/1339!, MA 79041!, W 1927-20437!).
Tamarix castellana Pau & Villar, Brotéria Ser. Bot. 23: 108 (1927)Pau C. & Huget del Villar E. 1927. Novae Tamaricis in Hispania centrali. Broteria 23: 101-113.. Type: Spain. Madrid, Vaciamadrid, 1911, F. Beltrán s.n. (lectotype designated by Villar & al. (2021: 283)Villar J.L., Alonso M.Á. & Crespo M.B. 2021. Remarks on the types of Tamarix names (Tamaricaceae) described from the Iberian Peninsula. Phytotaxa 484: 281-290. : MA 78874!).
Tamarix castellana f. rosea Pau & Villar, Brotéria Ser. Bot. 23: 109 (1927)Pau C. & Huget del Villar E. 1927. Novae Tamaricis in Hispania centrali. Broteria 23: 101-113.. Type: Spain. Madrid, Vaciamadrid, 18 Apr. 1926, H. Villar s.n. (holotype: MA 78871!).
Tamarix viciosoi Pau & Villar, Broteria Ser. Bot. 23: 109 (1927)Pau C. & Huget del Villar E. 1927. Novae Tamaricis in Hispania centrali. Broteria 23: 101-113.. Type: Spain. Madrid, Rivas de Jarama, 9 Jun. 1918, C. Vicioso s.n. (lectotype designated by Villar & al. (2021: 289)Villar J.L., Alonso M.Á. & Crespo M.B. 2021. Remarks on the types of Tamarix names (Tamaricaceae) described from the Iberian Peninsula. Phytotaxa 484: 281-290. : MA 78880!; isolectotype: MA 78879!).
Tamarix uncinatifolia Sennen, Ann. Soc. Linn. Lyon sér. 2,73: 9 (1928)Sennen F. 1928. Plantes d’Espagne, par le Fr. Sennen-Diagnoses et comentaires. Boletín de la Sociedad Ibérica de Ciencias Naturales 27: 66-67.. Type: Spain. Tarragona, Cambrils, Torrent de Janer, 8 Apr. 1917, fr. Sennen s.n. (lectotype designated by Villar & al. (2021: 288)Villar J.L., Alonso M.Á. & Crespo M.B. 2021. Remarks on the types of Tamarix names (Tamaricaceae) described from the Iberian Peninsula. Phytotaxa 484: 281-290. : MA 78985!; isolectotype: MA 78989!, W 1922-15231!, G 6990/1225!, G 6990/1224!).
Tamarix celtiberica Sennen & Elías, Bol. Soc. Ibér. Ci. Nat. 27: 66 (1928)Sennen F. 1928. Plantes d’Espagne, par le Fr. Sennen-Diagnoses et comentaires. Boletín de la Sociedad Ibérica de Ciencias Naturales 27: 66-67.. Type: Spain. Logroño, Recajo, Sables de l’Ebre, 10 May 1923, Hno. Elías s.n. [Pl. d’Espagne- F. Sennen 4988] (lectotype designated by Villar & al. (2021: 283)Villar J.L., Alonso M.Á. & Crespo M.B. 2021. Remarks on the types of Tamarix names (Tamaricaceae) described from the Iberian Peninsula. Phytotaxa 484: 281-290. : MA 78937!; isolectotypes: BCN 58933!, MA 78936!, G 6990-1226!, G 6990-1227!, W 1926-23534!).
Tamarix theodori Sennen, Pl. Espagne 1929, n.º 5945 (1929), in sched. Type: Spain. Tarragona, Cambrils, Pinar de la Llosa, 26 May, fr. Teodoro s.n. (lectotype designated by Villar & al. (2021: 288)Villar J.L., Alonso M.Á. & Crespo M.B. 2021. Remarks on the types of Tamarix names (Tamaricaceae) described from the Iberian Peninsula. Phytotaxa 484: 281-290. : MA 78038!; isolectotypes: BCN 58800!, MA 435537!, MA 78039!, W!, G 6990/1346!, G 6990/1348!).
Tamarix hieronymi Sennen, Diagn. Nouv. Pl. Espagne & Maroc 1928-35: 148 (1936). Type: Spain. Almería, Sierra de Enix, 3 Jun., Hno. Jerónimo s.n. [[Pl. d’Espagne- F. Sennen 8268] (lectotype designated by Villar & al. (2021: 284)Villar J.L., Alonso M.Á. & Crespo M.B. 2021. Remarks on the types of Tamarix names (Tamaricaceae) described from the Iberian Peninsula. Phytotaxa 484: 281-290. : MA 78991!, isolectotypes: G 6990/1335!, BCN 59562!, BCN 58932!, BC 75693 [photo!], VAL 157928-1!, MPU 022218!).
Description.-Deciduous shrubs or small trees that lose their leaves in late autumn. Flowering from early spring, generally only one bloom per year. New green shoots in late winter or early spring are short and condensed. Leaves 1-3 (4) mm long, ovate-triangular to lanceolate, acute, auriculate with narrow or broad and slightly decurrent base, sometimes embracing more than half the twig circumference. Inflorescence composed of racemes arranged in unbranched spike-like panicles or solitary, intermixed with new green shoots. Usually growing at the top of branches from the previous year. Racemes (15) 25-55 (70) × (4.5) 5.5-7 (8) mm, with a short peduncle < 5(8) mm densely covered by scarious bracts (fig. 1g). Rachis usually papillose. Bracts 1.5-3 (4) mm long, sub-equaling to slightly overpassing the calyx, broadly triangular to oblong, sometimes with scarious incurved apex, usually obtuse, with papillose margin, base narrow decurrent to calcarate, sometimes with 2 small decurrent auricules. Pedicels ca. 0.5 mm, shorter than sepals. Sepals 5 (rarely 4, exceptionally 6), broadly ovate to oblong, with an obtuse tip and a narrow hyaline margin entire or finely denticulate; (0.8) 1-1.5 (2.5) mm long, the 2 external ones are slightly larger and can show a prominent central nerve. Petals 5 (rarely 4, exceptionally 6), 2-3 (4) × 0.9-1.5 (2) mm, ovate to elliptic (sometimes oblong with cuneate or unguiculate base when they overpass 3 mm long). Filaments 5 (rarely 6-8, exceptionally 4), inserted on the top of the disc lobes, (when extra filaments are present, inserted between lobes). Anthers mostly not apiculate. Ovary always with 3 styles. Capsules 4.5-6 mm long.
Distribution.-Distributed mainly in the western Mediterranean Basin, extending to western Europe and Macaronesia. eastern and southern parts of the Iberian Peninsula, and Menorca (Balearic Islands). Fig. 2a.
Notes.-Specimens in the higher size ranges of inflorescence and floral parts (sometimes also with oblong-cuneate to oblong-unguiculate petals), have been frequently named Tamarix africana var. fluminensis (Maire) Baum. Some specimens from the Jarama river (Madrid) have been seen to show thinner racemes and secondary blooms resembling those of T. gallica, which might be a hint of hybridization between those species. Mediterranean French populations have seen to show longer pedicels (ca. 1.5 mm), even longer than sepals. Some specimens of T. africana were classified in the past as T. dalmatica (see Villar & al. 2012Villar J.L., Alonso M.Á., Juan A. & Crespo M.B. 2012. Does Tamarix dalmatica (Tamaricaceae) occur in Spain? Anales del Jardín Botánico de Madrid 69: 253-258. and further comments under the discussion of T. africana). A specimen with duplicated corolla and lacking androecium was found near Jaén by professor Carlos Salazar and a voucher is preserved at JAEN.
The specimen identified as Tamarix mascatensis (BCN 59562) by Gargano & al. (2018)Gargano M.L., Mandracchia G., Venturella G. & Calvo R. 2018. A revision of Tamarix specimens (Tamaricaceae) kept in the BCN herbarium of Barcelona (Spain). Flora Mediterranea 28: 393-397. is an isolectotype of T. hieronymi, which is a synonym of T. africana (Villar & al. 2021Villar J.L., Alonso M.Á. & Crespo M.B. 2021. Remarks on the types of Tamarix names (Tamaricaceae) described from the Iberian Peninsula. Phytotaxa 484: 281-290. ).
Tamarix aphylla (L.) H. Karst., Deut. Fl.: 641 (1882). Thuja aphylla L., Cent. Pl. 1: 32 (1755). Type: “Habitat in Aegypto” (lectotype designated by Burtt (in Burtt & Lewis 1954Burtt B.L. & Lewis P. 1954. On the Flora of Kuweit: III. Kew Bulletin 9: 377-410.): LINN 1136.3 [photo!]).
Description.-Perennial tree, sometimes surpassing 10 m high. Flowering in one main bloom from late summer throughout autumn. Leaves (0.75) 1-3 mm, vaginate, completely surrounding the twigs and forming a tube, with a triangular acute apex on one side (Fig. 1a). Inflorescence composed of racemes arranged in unbranched spike-like panicles at the end of green branches. Flowers arranged alternate in two distichous rows that grow spirally along the raceme. Racemes 25-70 × 4.5-5.5 mm, with short ebracteate peduncles or with a peduncle up to 1 cm long, with vaginate bracts. Bracts 1-1.5 (2) mm long, vaginate or, sometimes, amplexicaule at the base of racemes, divaricate below the pedicels, ended in a triangular acute-acuminate apex, not reaching the calyx apex. Pedicels very reduced, resulting in almost sessile flowers. Sepals 5, 1-1.6 × 0.9-1.5 mm, widely ovate to sub-orbicular, with obtuse apex and a small hyaline margin that is entire or sub-entire, the 2 external slightly smaller, concave and, sometimes, slightly keeled. Petals 5, 2-2.5 × 1 (1.4) mm, deciduous, though they can remain trapped between the calyx and the capsule, ovate-elliptical to oblong, concave and erect, forming a cup-shaped corolla (Fig. 1b). Stamens 5, filaments inserted between the disc lobes or abruptly over the disc lobes, sometimes the disc lobes are not evident and it is difficult to assign the insertion to one of the options mentioned. Anthers slightly apiculate. Ovary with 3 styles. Capsules 3-4 mm opened by 3 valves.
Distribution.-Distributed from northwestern Africa to southwestern Asia, and naturalized in the western Mediterranean basin, America and Australia. Scattered from the southern to the eastern parts of the Iberian Peninsula. Fig. 2b.
Notes.-In the specimens collected in Spain, we observed a very high proportion of unviable seeds inside each capsule. Unviable seeds were also observed in other species (Tamarix africana, T. boveana, T. gallica, and T. parviflora) but not in high proportions. It would be interesting to examine if this happens also in wild populations in the T. aphylla original distribution area, which covers a wide area in arid habitats between Morocco and Senegal in the west, and Pakistan and Afghanistan in the east (Baum 1978Baum B.R. 1978. The genus Tamarix. Israel Academy of Sciences and Humanities, Jerusalem. ). Most of the specimens collected and observed are cultivated and only one clearly naturalized has been seen by the authors (ABH 57455, ABH 71893, ABH 74668).
Tamarix boveana Bunge, Tent. Gen. Tamar.: 24 (1852)Bunge A. 1852. Tentamen Generis Tamaricum Species Accuratius Definiendi. J.C. Schuenmanni & C. Mattieseni, Dorpati.. Type: Algeria. Près de la Macta, 30 Apr. 1830, N. Bové s.n. (lectotype designated by Villar & al. (2015: 593)Villar J.L., Alonso M.Á., Juan A. & Crespo M.B. 2015. Remarks on typification of nineteen names in Tamarix (Tamaricaceae). Nordic Journal of Botany 33: 591-600.: P 00166715!; isolectotypes: B 100165200!, B 100165201!, G!, K 000242695!, K 000614109!, P 00166717!, P 05038533!, W 0031775!).
Tamarix jimenezii Pau, Bull. Acad. Int. Géogr. Bot. sér. 3, 16 (206): 75 (1906)Pau C. 1906. Synopsis formarum novarum hispanicarum cum synonimin nonnullis accedentibus. Bulletin de l’Académie Internationale de Géographie Botanique 206: 73-77. . Type: Spain. Murcia, Cartagena, Lopollo, 31 May 1903, F. Jiménez Munuera s.n. (lectotype designated by Villar & al. (2021: 285)Villar J.L., Alonso M.Á. & Crespo M.B. 2021. Remarks on the types of Tamarix names (Tamaricaceae) described from the Iberian Peninsula. Phytotaxa 484: 281-290. : MA 79004!).
Description.-Deciduous to marcescent shrubs or trees usually less than 4 m high, that can develop a lateral branch growth making them wider than higher. Main blooming period starts in late winter and extends to mid spring (depending on the climate); weak secondary blooms may occur through the spring or early summer. Leaves (1) 2-4 (5) mm long, narrowly lanceolate acute. In shoots developing from late summer to early winter, leaves are markedly auriculate and sometimes at the smaller size range. Each year´s new green shoots can also bear large basal and axillary leaves, 5-10 mm long, triangular-lanceolate, with a wide base (Fig. 1d). Inflorescence composed of generally solitary racemes that can appear at almost any part of the tree, intermixed with green shoots, and more frequent towards the tips of last year branches. Racemes (2.5) 40-120 (150) × 7-13 mm, very large, with a peduncle up to 1 cm long, with some long and wide oblong and slightly retrorse bracts, green at the beginning and yellowish-pale when the flowers are mature. Rachis from papillose to almost glabrous. Floral bracts 4-6 (7.5) × 0.5-1 mm, oblong-obtuse, sometimes with scarious incurved apex, base decurrent, divaricate to reflected at fruit stage, with papillose margin and surface, generally reaching or clearly surpassing the tip of the calyx (Fig. 1e); exceptionally 1-3 extra bracts can be found on the pedicels of basal flowers, these bracts being triangular linear and usually shorter than 2 mm. Pedicels 0.5-1.5 (2) mm, sometimes slightly recurved. Sepals 4 (rarely 5, exceptionally 6), (1.7) 2-3.5 (4) × (1.25) 1.5-2.5 (3) mm, ovate-elliptical, with a hyaline margin that is entire or finely and irregularly denticulate, sometimes eroded, the 2 internal obtuse, the 2 external slightly larger, commonly acute (rarely obtuse) to acuminate; when acuminate, the central nerve is strongly developed and the sepals may appear keeled. Petals 4 (rarely 5), (2.5) 3-4.5 (6) × 1.25-2.5 mm, elliptical-obovate to obovate-unguiculate, reflexed. Filaments 4 (rarely 5, very rarely 6-7), inserted on the top of disc lobes, the lobes short and filament insertion usually progressive, sometimes truncate; sometimes the stigmatic disc is very thin and circular, with no clear lobes, and then the insertion of filaments is progressive. Anthers not apiculate or, sometimes, very slightly apiculate. Ovary with 4 styles, rarely 3. Capsules 5-7 mm.
Distribution.-Distributed in northwestern Africa and the southwestern Mediterranean Basin. Southern and eastern Iberian Peninsula, including the Ebro basin, Mallorca, and Menorca (Balearic Islands). Fig. 2c.
Notes.-Secondary blooms are weak and occasional in this species. However, it is worth mentioning that they present racemes arranged in panicles and a high number of pentamerous flowers bearing shorter and thinner lanceolate bracts. Racemes in the shorter and longer size ranges are commonly found in a single tree. In some specimens, extra bracts are very close to the calyx, and they adopt the shape of a sepal (Villar & al. 2012Villar J.L., Alonso M.Á., Juan A. & Crespo M.B. 2012. Does Tamarix dalmatica (Tamaricaceae) occur in Spain? Anales del Jardín Botánico de Madrid 69: 253-258. ). Presence of additional bracts was strongly linked to T. rosea Bunge in Baum (1978)Baum B.R. 1978. The genus Tamarix. Israel Academy of Sciences and Humanities, Jerusalem. , although they have been later reported to a certain number of species (Villar & al. 2012Villar J.L., Alonso M.Á., Juan A. & Crespo M.B. 2012. Does Tamarix dalmatica (Tamaricaceae) occur in Spain? Anales del Jardín Botánico de Madrid 69: 253-258. ). Sepals reaching 3.5-4 mm have not been recorded out of Spain. The presence of T. dalmatica in the Iberian Peninsula was already discussed (Villar & al. 2012Villar J.L., Alonso M.Á., Juan A. & Crespo M.B. 2012. Does Tamarix dalmatica (Tamaricaceae) occur in Spain? Anales del Jardín Botánico de Madrid 69: 253-258. ). That piece of research included detailed study of type materials and specimens from T. dalmatica original range, as well as Iberian materials reported as T. dalmatica. The results showed great differences between the materials from the Adriatic coast and those collected in Spain. The latter were confused with T. boveana and, in a few cases, with T. africana. The specimen (BCN 41042) reported as T. dalmatica by Gargano & al. (2018)Gargano M.L., Mandracchia G., Venturella G. & Calvo R. 2018. A revision of Tamarix specimens (Tamaricaceae) kept in the BCN herbarium of Barcelona (Spain). Flora Mediterranea 28: 393-397. is here classified as T. boveana.
Tamarix meyeri belongs to a group of mostly tetramerous flowered and large raceme sized species. This group includes T. tetragyna, T. meyeri, T. boveana, T. brachystachys, and T. elongata (alongside several synonyms). Tamarix meyeri was described by Boissier (1849)Boissier E. 1849. Diagnoses Plantarum Orientalium Novarum ser. 1, 2(10): 8-10. M. Ducloux et Cons, Paris. and years later, the same author (Boissier 1867Boissier E. 1867. Flora Orientalis 1: 763-779. H. Georg, Gèneve.) regarded it as a variety of T. tetragyna. This same criterion was also followed by authors such as Zohary (1972)Zohary M. 1972. Tamarix L. In Zohary M. (ed.), Flora palaestina vol. 2: 350-362. Israel Academy of Sciences and Humanities, Jerusalem. [Reprint 1987]. and Qaiser (1981)Qaiser M. 1981. The genus Tamarix Linn. (Tamaricaceae) in Pakistan. Pakistan Journal of Botany 13: 107-158.. Recent molecular studies (Villar & al. 2019Villar J.L., Alonso M.Á., Juan A., Gaskin J. & Crespo M.B. 2019. Out of the Middle East: new phylogenetic insights in the genus Tamarix (Tamaricaceae). Journal of Systematics and Evolution 57: 488-507.) have provided certain support for a close relation between T. elongata, T. boveana, and T. tetragyna, but T. brachystachys and T. meyeri could not be included in the analyses. Therefore, a more detailed molecular and morphological study of this group of species and their synonyms would surely provide a basis upon which to make decisions on their taxonomic status. In the meantime, we know that the first and subsequent records of T. meyeri in the Iberian Peninsula (Venturella & al. 2012Venturella G., Gargano M.L. & Mandracchia G. 2012. First record of Tamarix meyeri (Tamaricaceae) for western Europe. Plant Biosystems 146: 484-489.; Gargano & al. 2018Gargano M.L., Mandracchia G., Venturella G. & Calvo R. 2018. A revision of Tamarix specimens (Tamaricaceae) kept in the BCN herbarium of Barcelona (Spain). Flora Mediterranea 28: 393-397. ) were based on the affirmation that those specimens “are characterized by a tetramerous paralophic disk and, therefore, clearly correspond to T. meyeri”. Nevertheless, as explained before, we recognize a considerable degree of variability with respect to the staminal disc. Moreover, the mentioned localities include sites widely known to maintain healthy populations of T. boveana, such as Cabo de Gata (Almería) and the Ebro River delta (Tarragona). After examining the specimens from BCN, we consider that material to belong to T. boveana.
Tamarix octandra has been scarcely reported since its publication (Bunge 1852Bunge A. 1852. Tentamen Generis Tamaricum Species Accuratius Definiendi. J.C. Schuenmanni & C. Mattieseni, Dorpati.), from some localities around the Caucasus, northern Iran, the northwestern Caspian shores, Krym, and Turkey (Gorschkova 1949Gorschkova S.G. 1949. Tamaricaceae. In Komarov V.L. (ed.), Flora URSS vol. 15: 290-327. Izdatelstvo Akademii Nauk SSSR, Moscow-Leningrad.; Schiman-Czeika 1964Schiman-Czeika H. 1964. Tamaricaceae. In Rechinger K.H. (ed.), Flora iranica vol. 4. Akademische Druck, Graz. ; Baum 1966Baum B.R. 1966. Monographic Revision of the genus Tamarix. Final research report for the USDA. Department of Botany. Hebrew University, Jerusalem., Zieliński 1993Zieliński J. 1993. Tamarix octandra (Tamaricaceae) a species new to Turkey. The Karaca Arboretum Magazine 2: 7-10.). Its identity as a species is well supported by molecular phylogenetic data (Villar & al. 2019Villar J.L., Alonso M.Á., Juan A., Gaskin J. & Crespo M.B. 2019. Out of the Middle East: new phylogenetic insights in the genus Tamarix (Tamaricaceae). Journal of Systematics and Evolution 57: 488-507.). In the Iberian Peninsula and the Balearic Islands, it could only be confused with a T. boveana with extra stamens in its flowers. The specimen (BCN 58996) reported as T. octandra by Gargano & al. (2018)Gargano M.L., Mandracchia G., Venturella G. & Calvo R. 2018. A revision of Tamarix specimens (Tamaricaceae) kept in the BCN herbarium of Barcelona (Spain). Flora Mediterranea 28: 393-397. consists of a loosely branched twig with immature racemes. Not a single opened flower could be found and the racemes, bracts and floral parts were underdeveloped. After opening several flowers buds from three racemes, we found no characters that could lead us to T. octandra. Our observations suggest an underdeveloped T. boveana individual.
Tamarix gallica L., Sp. Pl. 1: 270 (1753). Type: “Tamarix narbonensis gallica” Hortus Cliffortianus 111, Tamarix 1 (lectotype designated by Baum (1966: 35-36)Baum B.R. 1966. Monographic Revision of the genus Tamarix. Final research report for the USDA. Department of Botany. Hebrew University, Jerusalem.: BM 000558434 [photo!]).
Tamarix anglica Webb, J. Bot (Hooker) 3: 430 (1841)Webb P.B. 1841. Tamarix gallica of Linnaeus. Journal of Botany 3: 422-431.. Type: “Tamarix narbonensis” (lectotype designated by Baum (1966: 35)Baum B.R. 1966. Monographic Revision of the genus Tamarix. Final research report for the USDA. Department of Botany. Hebrew University, Jerusalem.: P-LA 00287245!).
Tamarix esperanzana Pau & Villar, Brotéria Ser. Bot. 23: 101 (1927)Pau C. & Huget del Villar E. 1927. Novae Tamaricis in Hispania centrali. Broteria 23: 101-113.. Type: Spain. Madrid, Aranjuez, 21 May 1897, C. Pau s.n. (lectotype designated by Villar & al. (2021: 284)Villar J.L., Alonso M.Á. & Crespo M.B. 2021. Remarks on the types of Tamarix names (Tamaricaceae) described from the Iberian Peninsula. Phytotaxa 484: 281-290. : MA 78910!).
Tamarix esperanzana var. majoriflora Pau & Villar, Broteria Ser. Bot. 23: 104 (1927)Pau C. & Huget del Villar E. 1927. Novae Tamaricis in Hispania centrali. Broteria 23: 101-113.. Type: Spain. Madrid, Ciempozuelos, 18 May 1897, C. Pau s.n. (lectotype designated by Villar & al. (2021: 284)Villar J.L., Alonso M.Á. & Crespo M.B. 2021. Remarks on the types of Tamarix names (Tamaricaceae) described from the Iberian Peninsula. Phytotaxa 484: 281-290. : MA 78908!).
Tamarix matritensis Pau & Villar, Broteria Ser. Bot. 23: 105 (1927)Pau C. & Huget del Villar E. 1927. Novae Tamaricis in Hispania centrali. Broteria 23: 101-113.. Type: Spain. Madrid, Aranjuez ad Laguna de Ontígola, 26 May 1919, C. Vicioso s.n. (lectotype designated by Villar & al. (2021: 286)Villar J.L., Alonso M.Á. & Crespo M.B. 2021. Remarks on the types of Tamarix names (Tamaricaceae) described from the Iberian Peninsula. Phytotaxa 484: 281-290. : MA 78890!; isolectotype: BC 22355 [photo!]).
Tamarix riojana Sennen & Elías, Bol. Soc. Ibér. Ci. Nat. 27 (3-4): 67 (1928)Sennen F. 1928. Plantes d’Espagne, par le Fr. Sennen-Diagnoses et comentaires. Boletín de la Sociedad Ibérica de Ciencias Naturales 27: 66-67.. Type: Spain. Logroño, Alcanale, bords de l’Ebre. 29 Aug. 1921, fr. Elías s.n. (lectotype designated by Villar & al. (2021: 287)Villar J.L., Alonso M.Á. & Crespo M.B. 2021. Remarks on the types of Tamarix names (Tamaricaceae) described from the Iberian Peninsula. Phytotaxa 484: 281-290. : MA 78815!; isolectotypes: MA 78915!, G 6990/1281!, G 6990/1280!, G 6990/1279!, W 1922-16790!, SEV 74925, SEV 75449, MPU 022209!, BCN 58968!, BC 75704 [photo!], L 2462526 [photo!]).
Tamarix brachylepis Sennen, Butl. Inst. Catalana Hist. Nat. 32: 90 (1932)Sennen F. 1932. Brèves diagnoses des formes nouvelles parues dans nos exsiccata “Plantes d’Espagne-F. Sennen”. Butlletí de la Institució Catalana d’Història Natural 32: 90.. Tamarix gallica var. brachylepis Sennen, Butl. Inst. Catalana Hist. Nat. 32: 90 (1932). Type: Spain. Barcelona, Castelldefels, 16 May 1929, fr. Sennen s.n. (lectotype designated by Villar & al. (2021: 282)Villar J.L., Alonso M.Á. & Crespo M.B. 2021. Remarks on the types of Tamarix names (Tamaricaceae) described from the Iberian Peninsula. Phytotaxa 484: 281-290. : MA 78916!; isolectotypes: MA 78915!, BCN 58976!, BC 84493 [photo!], G 6990/1295!, P 06618422!, W 1930-12296!).
Tamarix sireti Sennen, Butl. Inst. Catalana Hist. Nat. 32(4-6): 110 (1932)Sennen F. 1932. Brèves diagnoses des formes nouvelles parues dans nos exsiccata “Plantes d’Espagne-F. Sennen”. Butlletí de la Institució Catalana d’Història Natural 32: 90.. Type: Spain. Almería, Cuevas de Vera, berges de l’Almanzora, 14 Jul. 1929, fr. Sennen & Jerónimo s.n. (lectotype designated by Villar & al. (2021: 288)Villar J.L., Alonso M.Á. & Crespo M.B. 2021. Remarks on the types of Tamarix names (Tamaricaceae) described from the Iberian Peninsula. Phytotaxa 484: 281-290. : MA 78917!; isolectotypes: BCN 58970!, W 1930-12213!, G 6990/1277!, G 6990/1278!, P 06618791!, RAB 013567!).
Description.-Deciduous to marcescent shrubs or trees that lose their leaves in late autumn, 2 to 8 m high. Main bloom starts at mid-late spring in the warmer areas; secondary blooms may take place from early summer and, especially in late summer and early autumn. Leaves 1-2 (3) mm long, very variable in shape, ovate-lanceolate to lanceolate, acute, more or less auriculate, with narrow slightly decurrent base, usually not embracing more than half the twig circumference, more auriculate towards the end of the year. Inflorescence composed of racemes arranged in unbranched spike-like panicles, slightly ramified panicles or, especially in secondary and late blooms, in compound panicles. Sometimes racemes can also grow in fascicles. Racemes (10) 20-55 (100) × 3.5-5 (5.5) mm, with variable peduncles (<2-5 (10) mm), The shorter ones naked, the longer sparsely covered by 4-11 green or scarious broad based, leaf-like bracts. Rachis glabrous or sometimes papillose at first spring bloom, clearly papillose at secondary and late blooms throughout the summer and early autumn. Bracts (0.75) 1-1.75 (2.5) mm long, generally scarious and papillose, at least on the margins of the basal part, from ovate-obtuse with wide base not equaling the calyx top, to narrowly subulate with narrow and slightly decurrent base and commonly overpassing the calyx apex (Fig. 1h). Pedicels usually shorter than 0.5 mm, shorter than sepals, when longer (up to 1 mm), they influence the relative length of bracts in respect to the calyx top level and in relation to sepal length. Sepals 5, 0.6-0.9 × 0.4-0.7 (0.8) mm, ovate to triangular ovate, with the tip generally obtuse, sometimes acute, with a subentire margin, finely serrulate; the 2 external ones can show a marked central nerve and be more acute tipped. Petals 5 (exceptionally 6 or 7), (1) 1.2-1.7 (2) × 0.6-1 (1.2) mm, elliptic, elliptic-obovate or oblong-elliptic, less frequently elliptic ovate. Filaments 5 (rarely 6 to 8), usually arising smoothly from the disc lobes or inserted on top of them. Anthers slightly apiculate. Ovary always with 3 styles. Capsules 2.5-4 mm long.
Distribution.-Distributed in western Europe and the western Mediterranean basin. Widespread in the Iberian Peninsula and the Balearic Islands. Fig. 2d.
Notes.-Racemes reaching 5.5 mm wide were associated with uncommon elongation of pedicels, while the remaining floral parts conform with typical measures. Moreover, these extra wide racemes are mixed with racemes of normal width within the same tree. Racemes reaching extreme length (10 cm) were observed in one tree (ABH 77211). This tree was visited at different times later, and its racemes showed normal size. Petal shape varies from slightly obovate to slightly ovate in single individuals. Sometimes disc lobes are not prominent and there are cases in which the disk could even be classified as hololophic, according to Baum (1978)Baum B.R. 1978. The genus Tamarix. Israel Academy of Sciences and Humanities, Jerusalem. . Several specimens falling under the morphological description provided in the present study have been classified as T. canariensis since the 1970’s.
One of the most controversial issues about the identification of Tamarix in the Iberian Peninsula has been the distinction between T. canariensis and T. gallica. Both species are highly similar in morphology. However, T. canariensis has not been commonly cited out of the Canary Islands and it was even synonymized to T. gallica by early authors such as Webb (1841)Webb P.B. 1841. Tamarix gallica of Linnaeus. Journal of Botany 3: 422-431.. Baum’s (1966Baum B.R. 1966. Monographic Revision of the genus Tamarix. Final research report for the USDA. Department of Botany. Hebrew University, Jerusalem., 1978Baum B.R. 1978. The genus Tamarix. Israel Academy of Sciences and Humanities, Jerusalem. ) interpretation of T. canariensis expanded its distribution to Morocco, Algeria, Tunisia, Corsica, Sardinia, France, Spain and Portugal. Thus, the numerous previous records of T. gallica in north-western Africa were assigned to T. canariensis, whereas the distribution of T. gallica was mostly constrained to south-western Europe. A set of characters for each species was provided by Baum (1966)Baum B.R. 1966. Monographic Revision of the genus Tamarix. Final research report for the USDA. Department of Botany. Hebrew University, Jerusalem., including shape and size of petals, shape of sepals, shape and relative length of bracts and presence or absence of papillae on the rachis of floral racemes. This interpretation was later followed in regional and local floras (Cirujano 1993Cirujano S. 1993. Tamarix L. In Castroviejo S., Aedo C., Cirujano S., Laínz M., Monserrat P., Morales R., Muñoz Garmendia F., Navarro C., Paiva J. & Soriano C. (eds.), Flora iberica vol. 3: 437-443. Real Jardín Botánico, CSIC, Madrid.; Salazar & Quesada 2011Salazar C. & Quesada J. 2011. Tamarix L. In Blanca G., Cabezudo B., Cueto M., Morales Torres C. & Salazar C. (eds.), Flora vascular de Andalucía Oriental ed. 2, vol. 2: 590-593. Universities of Almería, Granada, Jaén and Málaga, Granada.; Mateo & Crespo 2014Mateo G. & Crespo M.B. 2014. Claves ilustradas para la Flora Valenciana. [Colección Monografías de Flora Montiberica, nº 6]. Jolube Ed., Jaca.). Nevertheless, the set of characters assigned to each species often overlap when identifying specimens of wild populations, making identification difficult. Indeed, in recent years, we showed that both sets of characters could be found in a single tree across the year or even at the same time. Herbarium sheets coming from single individuals but collected at different times of the year are kept at the ABH. Typically, the set of characters usually related to T. gallica was mostly found in the first spring bloom, whilst the characters assigned to T. canariensis tended to appear progressively in secondary blooms, being very clear in late-summer and autumn racemes. Based on the phylogenetic data available (Villar & al. 2019Villar J.L., Alonso M.Á., Juan A., Gaskin J. & Crespo M.B. 2019. Out of the Middle East: new phylogenetic insights in the genus Tamarix (Tamaricaceae). Journal of Systematics and Evolution 57: 488-507.), it was demonstrated that individuals of T. canariensis from the Canaries were genetically very distant to T. gallica (including specimens reported as T. canariensis outside the Canaries). Nevertheless, we have not found clear morphological characters to separate these species. Therefore, as it was explained in Villar & al. (2019)Villar J.L., Alonso M.Á., Juan A., Gaskin J. & Crespo M.B. 2019. Out of the Middle East: new phylogenetic insights in the genus Tamarix (Tamaricaceae). Journal of Systematics and Evolution 57: 488-507., in the light of phylogenetic data, we only recognize T. gallica for those records of both species made in north-western Continental Africa and south-western Europe. These results are congruent with Terzoli & al. (2014)Terzoli S., Abbruzense G., Beritognolo I., Sabatti M., Valentini R. & Kuzminsky E. 2014. Genetic characterization of a Tamarix spp. germoplasm collection in Italy. Botany 92: 360-369. , who found no genetic differences for Italian T. canariensis and T. gallica. This would confirm that all those Italian T. canariensis specimens were, in fact, T. gallica. More recently, Bihaoui & al. (2020)Bihaoui A., Haddioui A. & Hammada S. 2020. Les erreurs d’identification des espèces du genre Tamarix L. au Maroc: Clés non uniformes et especès polymorphes. Ecologia mediterranea 46: 49-61. , also had great difficulties distinguishing between both species because of the great plasticity in the characters commonly used for identification. Further genetic studies will be needed to determine the true extension of the distribution of T. canariensis, which has only been assessed from specimens collected in Tenerife and Gran Canaria.
The presence of Tamarix mascatensis was also recently discarded (Villar & Alonso 2016Villar J.L. & Alonso M.Á. 2016. Tamarix mascatensis. In Raab-Straube E. von & Raus T. (eds.), Euto+Med Checklist Notulae 6. Willdenowia 46: 423-442.), and neither the specimens nor the previous descriptions provided by De Martis & al. (1985)De Martis B., Loi M.C. & Polo M.B. 1985. Tamarix mascatensis Bge. (Tamaricaceae) in Portogallo, nuova per la flora d’Europa. Boletim da Sociedade Broteriana 58: 215-217. and Cirujano (1993)Cirujano S. 1993. Tamarix L. In Castroviejo S., Aedo C., Cirujano S., Laínz M., Monserrat P., Morales R., Muñoz Garmendia F., Navarro C., Paiva J. & Soriano C. (eds.), Flora iberica vol. 3: 437-443. Real Jardín Botánico, CSIC, Madrid., matched the characters of the original material from T. mascatensis. The specimens studied by Villar & Alonso (2016)Villar J.L. & Alonso M.Á. 2016. Tamarix mascatensis. In Raab-Straube E. von & Raus T. (eds.), Euto+Med Checklist Notulae 6. Willdenowia 46: 423-442. were found to belong to T. gallica. Most identifications gave high importance to the staminal disc, but obviated a key character already mentioned in the original description (Bunge 1852Bunge A. 1852. Tentamen Generis Tamaricum Species Accuratius Definiendi. J.C. Schuenmanni & C. Mattieseni, Dorpati.), such as the strongly amplexicaule leaves, almost vaginate.
Tamarix arborea was first cited by Gargano & al. (2009)Gargano M.L., Mandracchia G & Venturella G. 2009. Tamarix arborea var. subvelutina (Tamaricaceae), new from Spain. Lagascalia 29: 320-321., including both of the varieties recognized by Baum (1966)Baum B.R. 1966. Monographic Revision of the genus Tamarix. Final research report for the USDA. Department of Botany. Hebrew University, Jerusalem.. Probably, the first identification of this species in the Iberian Peninsula dates from a specimen kept in the herbarium of the University of Málaga (MGC 11349). That specimen was collected by López and Nieto in May 1982 and initially classified as T. gallica. In 1989, Loi and De Martis identified it as T. arborea. That same specimen has recently been re-assigned to T. gallica by Soriguer, an identification in which we totally agree. The identity of T. arborea is complicated. Having observed type materials and gatherings from the area from which it was described (El Cairo, Egypt), we may say that the most significant difference with T. gallica is the shape of the leaves, which tend to embrace more than half the twig circumference. Moreover, there is a clearly close relation of this species with T. nilotica (Ehrenb.) Bunge, even reflected in a rather heterogeneous type collection of T. arborea, that includes specimens that can be assigned to either species. In fact, Zohary (1972)Zohary M. 1972. Tamarix L. In Zohary M. (ed.), Flora palaestina vol. 2: 350-362. Israel Academy of Sciences and Humanities, Jerusalem. [Reprint 1987]. included T. arborea as a synonym of T. nilotica, alongside other names such as T. mannifera and T. arabica. These relations remained unclear in our recent phylogenetic work (Villar & al. 2019Villar J.L., Alonso M.Á., Juan A., Gaskin J. & Crespo M.B. 2019. Out of the Middle East: new phylogenetic insights in the genus Tamarix (Tamaricaceae). Journal of Systematics and Evolution 57: 488-507.), but they were clearly apart from the clade including T. gallica. It would be helpful to confirm suspicious cases by using molecular data. Nevertheless, according to our observations of the materials kept at BCN, the high percentage of T. arborea identifications in Gargano & al. (2018)Gargano M.L., Mandracchia G., Venturella G. & Calvo R. 2018. A revision of Tamarix specimens (Tamaricaceae) kept in the BCN herbarium of Barcelona (Spain). Flora Mediterranea 28: 393-397. is due to misidentifications. After detailed analysis of the BCN specimens classified by Gargano & al. (2018)Gargano M.L., Mandracchia G., Venturella G. & Calvo R. 2018. A revision of Tamarix specimens (Tamaricaceae) kept in the BCN herbarium of Barcelona (Spain). Flora Mediterranea 28: 393-397. as T. arborea. It is evident that our approaches on Tamarix species identification differ greatly. These discrepancies with our colleagues give another insight on the taxonomic challenge presented by this genus. Under our interpretation, all those specimens can be easily identified as either T. africana or T. gallica. The only specimen (BCN 58947) reported as T. arborea var. subvellutina is here assigned to T. africana.
Tamarix mannifera was reported by Gargano & al. (2018)Gargano M.L., Mandracchia G., Venturella G. & Calvo R. 2018. A revision of Tamarix specimens (Tamaricaceae) kept in the BCN herbarium of Barcelona (Spain). Flora Mediterranea 28: 393-397. on three specimens previously identified as T. canariensis (BCN 58965, BCN 58966, BCN 58970). One of them (BCN 58970) is, indeed an isolectotype of T. sireti Sennen. According to our interpretation, all three specimens represent late blooms of T. gallica. Therefore, we cannot give support to the presence of T. mannifera in the Iberian Peninsula.
Tamarix rosea is a taxon of difficult interpretation. Its description (Bunge 1852Bunge A. 1852. Tentamen Generis Tamaricum Species Accuratius Definiendi. J.C. Schuenmanni & C. Mattieseni, Dorpati.) noted some features that probably do not reflect the most common features of a Tamarix species, such as heptandrous flowers (bearing almost always 7 stamens) and flowers with 5 or 6 petals. Later, Baum (1966)Baum B.R. 1966. Monographic Revision of the genus Tamarix. Final research report for the USDA. Department of Botany. Hebrew University, Jerusalem. added a new uncommon character, such as bearing 2 or 3 bracts in, at least, some flowers in each raceme. The type materials, observed at G and especially at P, do not allow to confirm such features, in part, due to the impossibility of examining flowers without greatly damaging the specimens. The specimen kept at G shows, indeed, a morphology that could match with the late bloom of T. hohenckeri Bunge, though the state of the specimen does not allow to confirm if the petals are persistent or not, as suggested by Bunge (1852). To add more confusion, Gorschkova (1949)Gorschkova S.G. 1949. Tamaricaceae. In Komarov V.L. (ed.), Flora URSS vol. 15: 290-327. Izdatelstvo Akademii Nauk SSSR, Moscow-Leningrad. included T. rosea as a synonym of T. octandra. A synonymyzation that is difficult to support attending to the type materials available. Another example is the inclusion (Baum 1966Baum B.R. 1966. Monographic Revision of the genus Tamarix. Final research report for the USDA. Department of Botany. Hebrew University, Jerusalem.) of the specimens belonging to the gathering Balansa 130 (type material for T. hampeana var. smyrnea Boiss.) into T. rosea, even mentioning that it could be a transitional form between T. hampeana and T. rosea. In our opinion, the specimens of Balansa 130 are clear examples of T. hampeana (Villar 2017Villar J.L. 2017. Tamarix. Euro+Med Plantbase. The information resource for Euro-Mediterranean plant diversity. Website: http://ww2.bgbm.org/EuroPlusMed/PTaxonDetail.asp?NameId=34690&PTRefFk=7500000 [accessed: 1 Sep. 2022]), despite the extra bracts in some flowers. Lately, T. rosea has also been included as a synonym of T. hohenackeri in the catalogue of life (Hassler 2020Hassler M. 2020. World Plants: Synonymic Checklists of the Vascular Plants of the World (version Sep 2020). In Roskov Y., Ower G., Orrell T., Nicolson D., Bailly N., Kirk P.M., Bourgoin T., DeWalt R.E., Decock W., van Nieukerken E.J. & Penev L. (eds.), Species 2000 & ITIS Catalogue of Life, 2020-12-01. Species 2000: Naturalis, Leiden, the Netherlands. Website: www.catalogueoflife.org [accessed 1 Sep. 2022].). The specimen (BCN 58989) identified as T. rosea by Gargano & al. (2018)Gargano M.L., Mandracchia G., Venturella G. & Calvo R. 2018. A revision of Tamarix specimens (Tamaricaceae) kept in the BCN herbarium of Barcelona (Spain). Flora Mediterranea 28: 393-397. shows the typical features of T. gallica except for the insertion of the staminal filaments into the disc, which is not clearly assignable to a category. According to our data, the morphology of this specimen must not lead to the recognition of a new species for the Iberian Peninsula, especially if it means the inclusion of such a controversial species as T. rosea.
Tamarix parviflora DC., Prodr. 3: 97 (1828). Type: Turkey: “Constantinople. 1822. M. Louis Castagne 24” (holotype: G-DC).
Tamarix lucronensis Sennen & Elías, Bol. Soc. Ibér. Ci. Nat. 27 (3-4): 67 (1928)Sennen F. 1928. Plantes d’Espagne, par le Fr. Sennen-Diagnoses et comentaires. Boletín de la Sociedad Ibérica de Ciencias Naturales 27: 66-67.. Type: Spain. La Rioja, Herrera, 29 May 1923, fr. Elías s.n. (lectotype designated by Villar & al. (2021: 285)Villar J.L., Alonso M.Á. & Crespo M.B. 2021. Remarks on the types of Tamarix names (Tamaricaceae) described from the Iberian Peninsula. Phytotaxa 484: 281-290. : MA 78791!; isolectotypes: BCN 59557!, G 6990/1340!, G 6990/1341!, L 101910 [photo!], SEV 92127, MPU 022217!).
Description.-Deciduous shrubs or trees usually less than 4 m high. Main bloom from late winter to early-mid spring. Secondary blooms extremely uncommon. Leaves 1-3 mm long, triangular-lanceolate to lanceolate acute, with a narrow decurrent base, sometimes slightly auriculate. Inflorescence composed of generally solitary, sometimes fasciculate racemes that usually appear in last year’s branches before the new green shoots start growing, more frequent towards the branch tips. Racemes 20-40 (50) × 4-5 (5.5) mm, with a short peduncle less than 5 mm, with 2 to 5 bracts, leaf like or scariose and grouped at the base. Rachis usually glabrous. Floral bracts 1-1.8 (2) × 0.5-0.8 mm, triangular-oblong, divaricate, concave, base narrow and decurrent, apex incurved and obtuse, with entire margins or, sometimes, slightly papillose at the base, generally not reaching the tip of the calyx. Pedicels usually shorter than 0.5 mm (rarely reaching 1 mm). Sepals 4, 0.75-1.25 × 0.6-1 mm, with a hyaline entire to irregular margin, sometimes pink-purple coloured towards the tip (Fig. 1c), the outer 2 triangular ovate-acute, sometimes with a marked central nerve, the inner 2 elliptical and obtuse, all concrescent at the pedicel, making it difficult to establish the start of the sepal. Petals 4, (1.6) 1.75-2.25 (2.5) × 0.75-1.2 (1.5) mm, trullate ovate to oblong cuneate or even elliptic-obovate, incurved to retrorse. Filaments 4 (rarely 5), smoothly rising from the top of disc lobes, which sometimes shows a cruciform shape. Anthers generally apiculate. Ovary with 4 (3) styles. Capsules 3.5-5 (5.5) mm.
Distribution.-Distributed in the eastern Mediterranean basin, northern Africa and southwestern Asia. Cultivated and naturalized mostly in the coastal areas of the eastern, southern and northern Iberian Peninsula, with some localities in central Spain. Fig. 2e.
Notes.-Secondary blooms seem to be rare in this species. However, when happening, flowers can show a variety of rare features such as pentamery or an uncertain number of extra stamens that can greatly difficult a proper identification.
Tamarix gr. ramosissima Ledeb., Fl. Altaic. 1: 424 (1829).
Description.-Deciduous shrubs or trees usually less than 4 m high. Flowering several times from spring to autumn. Leaves 1-3 mm long, ovate-triangular to triangular-lanceolate, acute at the apex, with a narrow and slightly decurrent base, sometimes slightly auriculate. Inflorescence composed of racemes arranged in loosely compound panicles in the apical part of, generally, new branches. Racemes 25-50 (80) × 3.5-5 mm, with a short (2-8 mm) naked peduncle, or bearing a few leaflike bracts. Rachis usually glabrous. Floral bracts 0.75-2 (2.5) mm long, narrowly triangular, lanceolate or subulate, with a narrow and slightly decurrent base with entire margins or, sometimes, slightly papillose-denticulate at its basal third, generally not reaching the tip of the calyx, or slightly surpassing it, though this character strongly depends on pedicel length. Pedicels 0.2-1 (1.5) mm. Sepals 5, 0.6-1 × 0.5-75 mm, triangular-ovate, mainly acute though they can sometimes be obtuse at the tip, with a hyaline sub-entire to finely serrulate margin, the two outer ones sometimes showing a marked central nerve. Petals 5, 1-2 × 0.6-1 mm, obovate, elliptic or wide elliptic, rarely elliptic ovate, frequently inequilateral at their upper part, concave and persistent, forming a cup shaped corolla (Fig. 1i). Filaments 5, inserted between the disc lobes. Anthers generally not apiculate. Ovary with 3 styles. Capsules 3-4.2 mm.
Distribution.-Native to central and eastern Asia, but widely cultivated and naturalized in many parts of the world. Some localities in northern and southeastern Spain. Fig. 2f.
Notes.- Baum (1966)Baum B.R. 1966. Monographic Revision of the genus Tamarix. Final research report for the USDA. Department of Botany. Hebrew University, Jerusalem. mentioned the specimen K 000341731 as a fragment of the holotype, but his previous discussion on the matter of Tamarix ramosissima type material makes clear that some uncertainty remains. Moreover, as it is stated on the Report of the Nomenclature Committee for Vascular Plants 68 (Wilson 2017: 480Wilson K.L. 2017. Report of the General Committee 17. Taxon 66: 478-480. ), the selected specimens can not be clearly linked to Ledebour (1829)Ledebour C.F. 1829. Flora altaica vol. 1. G. Reimeri, Berlin. protologue, and possible original material at LE was not studied. Therefore, the status of these vouchers could undergo some changes in the future. Iberian specimens identified as either T. ramosissima or T. chinensis are found in herbaria. Alongside other species (T. austromongolica Nakai, T. smyrnensis Bunge and T. hohenackeri), they share the very characteristic persistent petals. This group would basically match Series Xeropetalae Bunge (Bunge 1852). The resemblance of T. ramosissima and T. chinensis has been widely discussed over the last decades (Baum 1978Baum B.R. 1978. The genus Tamarix. Israel Academy of Sciences and Humanities, Jerusalem. ; Cirujano 1993Cirujano S. 1993. Tamarix L. In Castroviejo S., Aedo C., Cirujano S., Laínz M., Monserrat P., Morales R., Muñoz Garmendia F., Navarro C., Paiva J. & Soriano C. (eds.), Flora iberica vol. 3: 437-443. Real Jardín Botánico, CSIC, Madrid.) and hybrid forms are widely distributed out of their respective native areas (Gaskin & Schaal 2003Gaskin J.F. & Schaal B. 2003. Hybrid Tamarix widespread in U.S. invasion and undetected in native Asian range. Proceedings of the National Academy of Sciences 99: 11256-11259.). The features observed in the type of T. chinensis present in the Loureiro herbarium (at P) greatly match with the morphology observed in T. ramosissima from collections nearby the original location of the latter. We have taken this with caution, since we have only been able to see a few specimens that would undoubtedly belong to T. chinensis and maybe, other regional treatments (Yang & Gaskin 2007Yang Q. & Gaskin J.F. 2007. Tamarix. In Zhengyi W. & Raven P.H. (eds.), Flora of China 13: 59-65. Science Press, Beijin, & Missouri Botanical Garden Press, St. Louis.) could provide a better understanding of this group. However, in the light of the difficulties sometimes found to classify this kind of specimens under one of the two aforementioned names, we have classified them as Tamarix group ramosissima (T. gr. ramosissima). This decision is also supported by the fact that most of the specimens found (mainly cultivated) seem to match with what nurseries sell as T. ramosissima “pink cascade”. We hope further studies on this group will help to clairfy the issues regarding the names included upon it.
Tamarix × verae J.L.Villar, M.Á.Alonso & M.B.Crespo, nothosp. nov. Parentals: Tamarix boveana Bunge × Tamarix gallica L. Type: Spain. Elche, Clot de Galvany, 30SYH1635, 9 m, 7 Apr. 2022, J.L. Villar T217A (holotype: ABH 81571!). Fig. 3.
Diagnosis.-General aspect similar to Tamarix boveana, but with clear differences in characters such as the arrangement of racemes, more similar to T. gallica, the smaller size of the floral parts and a clear tendency to pentamery. These intermediate features can show similar proportions to T. africana, but it can be easily distinguished from the latter by its flexuose bracts, the less condensed green spring shoots, the shape of floral parts and the hypersaline habitats this hybrid shares with both parentals, but not with T. africana.
Eponymy.-The hybrid’s name is dedicated to the first author’s daughter, Vera.
Description.-Deciduous shrubs or trees, usually less than 4 m high. Blooming in spring. Leaves 1.5-3.5 (9) mm long, ovate-triangular to narrowly lanceolate, with narrow and slightly decurrent base, sometimes slightly auriculate. Inflorescence composed of generally solitary racemes, sometimes fasciculate, more frequent towards the tips of branches, new or old, sometimes forming unbranched panicles. Racemes (20) 30-60 (70) × 6-7.5 (9) mm, with a peduncle up to 2-10 mm long, with sparse wide bracts, oblong to triangular, scarious. Rachis of the racemes glabrous or not evidently papillose. Floral bracts 2.7-3.5 (4.5) × 0.6-0.8 mm, oblong-obtuse, wide triangular or subulate, sometimes flexuose in their upper part, base narrow and slightly decurrent, sometimes with a papillose margin, generally reaching or slightly surpassing the tip of the calyx. Pedicels 0.5-1 mm. Sepals 5, but flowers with 4 sepals are frequent (exceptionally 6), 1.2-1.5 (2) × 0.8-1.2 mm, ovate triangular or ovate, with a hyaline margin that is entire or finely and irregularly denticulate, sometimes eroded, the 2-3 internal obtuse, the 2 external sometimes acute. Petals 5 (rarely 4), 2.25-3 × 0.8-1.5 mm, oblong obovate to oblong, rarely trullate ovate, retrorse at maturity. Filaments 5 (rarely 4 or 6), the antesepalous inserted on the top of disc lobes, Anthers not apiculate or, sometimes, very slightly apiculate. Ovary with 3 styles, rarely 4. Capsules 3.75-5 mm.
Notes.-All specimens of this hybrid were observed in localities where both parent species were present and very close to each other. When tetrasepalous flowers were found, the calyx greatly resembled to that of T. boveana at a smaller scale. Many tetrasepalous flowers were found to be pentapetalous and pentandrous. Some pentasepalous flowers showed 2 sepals almost overlapping, needing careful manipulation in order not to classify them as tetrasepalous. Sometimes, the fifth sepal showed a mixed sepal-petal morphology.
DISCUSSION
⌅Only seven species are recognized in the present work for the Iberian Peninsula and the Balearic Islands. The status of other species reported to those territories is discussed under each of the recognized species in the treatment above. Many of these identifications seem to be derived from an extensive use of Baum’s monograph key (Baum 1978Baum B.R. 1978. The genus Tamarix. Israel Academy of Sciences and Humanities, Jerusalem. ), and an excessive reliance on the stability of some characters that, according to our studies, are more variable than previously reported. Over the next paragraphs, some examples of how this could affect the identification of the most common Iberian and Balearic species are provided.
One of the key features used by Baum (1966Baum B.R. 1966. Monographic Revision of the genus Tamarix. Final research report for the USDA. Department of Botany. Hebrew University, Jerusalem., 1978Baum B.R. 1978. The genus Tamarix. Israel Academy of Sciences and Humanities, Jerusalem. ) is the shape of the nectariferous disc, which was divided in synlophic, paralophic and hololophic, depending on the insertion of the staminal filaments. This character has lately been regarded to show certain plasticity within the species natural variability (Zohary 1972Zohary M. 1972. Tamarix L. In Zohary M. (ed.), Flora palaestina vol. 2: 350-362. Israel Academy of Sciences and Humanities, Jerusalem. [Reprint 1987].; Villar & al. 2012Villar J.L., Alonso M.Á., Juan A. & Crespo M.B. 2012. Does Tamarix dalmatica (Tamaricaceae) occur in Spain? Anales del Jardín Botánico de Madrid 69: 253-258. ). In the mentioned key, the three main Iberian Tamarix species are considered to show a synlophic disc. A strict interpretation of the disc shape, under the three mentioned categories, would mean that T. gallica would never be selected if the identifier considered the disc as paralophic. Nevertheless, this could lead to records of T. mascatensis or T. arborea, whose discs were regarded as paralophic (Baum 1978Baum B.R. 1978. The genus Tamarix. Israel Academy of Sciences and Humanities, Jerusalem. ). Similarly, a standard specimen of T. boveana could not be properly identified if someone considered the disc as paralophic. Under this circumstance, such specimen would easily be identified as T. meyeri or T. dalmatica. Even to get to T. africana, anyone will find a last step in which, if the disc is considered paralophic, the final result would be T. tetragyna. Therefore, as it can be seen in the species description provided, a less strict interpretation of the disc shape should better represent the real variability of the Iberian and Balearic Tamarix species, and would probably result in a lesser number of conflicting identifications.
Another conflicting character is the number of stamens, regarded as haplostemonous, when the number of stamens matches the number of calyx pieces; diplostemonous, when the filaments are double than sepals; and partially diplostemonous, when extra filaments appear in an haplostemonous disc, without reaching numbers double than sepals. Other terms such as triplostemonous and partially triplostemonous do not apply to any of the Iberian or Balearic reported species. None of the species recognized in this article can be reached if the entry of “diplostemonous or partially diplostemonous discs is followed”. This entry would easily lead a T. africana with some proportion of extra staminal filaments, to be easily identified as T. tetragyna. This derivation has probably happened in the past in other regions. For instance, the description and the figure appearing in De Martis & al. (1984)De Martis B., Loi M.C. & Polo M.B. 1984. Il genere Tamarix L. (Tamaricaceae) in Sardegna. Webbia 37: 211-235. for Sardinia, seems to be closer to T. africana than to T. tetragyna. Indeed, it seems that the general conception of T. tetragyna that derives from Baum (1978)Baum B.R. 1978. The genus Tamarix. Israel Academy of Sciences and Humanities, Jerusalem. remarks too much the special features (such as pentamerous flowers and extra stamens), instead of in its most common features (haplostemonous tetramerous flowers) placing it as something similar to a T. africana with extra filaments. However, according to our observations, T. tetragyna is a very similar species to T. boveana. Both species can show some pentamerous flowers, which can be dominant in secondary blooms, but their main blooms consist of large tetramerous flowered racemes. The presence of mostly pentamerous flowers in aestival racemes was well documented by Baum (1966)Baum B.R. 1966. Monographic Revision of the genus Tamarix. Final research report for the USDA. Department of Botany. Hebrew University, Jerusalem. for T. tetragyna but not for T. boveana, maybe for the practical lack of specimens showing this feature in the available herbarium materials. A strong relation between the aforementioned species is supported by the phylogenetic data available (Villar & al.; 2019Villar J.L., Alonso M.Á., Juan A., Gaskin J. & Crespo M.B. 2019. Out of the Middle East: new phylogenetic insights in the genus Tamarix (Tamaricaceae). Journal of Systematics and Evolution 57: 488-507.).
In such a complicated genus as Tamarix, it would be recommendable to follow the approach of Piirainen & al. (2017)Piirainen M., Liebisch O. & Kadereit G. 2017. Phylogeny, biogeography, systematics and taxonomy of Salicornioideae (Amaranthaceae/Chenopodiaceae) - A cosmopolitan, highly specialized hygrohalophyte lineage dating back to the Oligocene. Taxon 66: 109-132., and generate (when not available) regional keys instead of using a global one. Using a global key in a genus with species showing similar characters but living in distant areas can lead to doubtful records and rare extension of previously expected distribution areas for each species. A more complete phylogeny and access to genomic information could also help confirm or discard identifications out of the expected range of each species.
When collecting Tamarix specimens, it would be useful to take the phenology into consideration, trying to gather the specimens during the first bloom of the year, when diagnostic characters tend to be more stable (Baum 1978Baum B.R. 1978. The genus Tamarix. Israel Academy of Sciences and Humanities, Jerusalem. ; Villar & al. 2012Villar J.L., Alonso M.Á., Juan A. & Crespo M.B. 2012. Does Tamarix dalmatica (Tamaricaceae) occur in Spain? Anales del Jardín Botánico de Madrid 69: 253-258. ). In relation to this, it is necessary to recognize that certain unexpected characters can eventually show up. However, specimens with unexpected characters can normally fit into the variation of one of the local species. If an identification gets to the point of no possible fitting in any of the local species, molecular analyses can be helpful to compare our specimens with the previously available data (Villar & al. 2019Villar J.L., Alonso M.Á., Juan A., Gaskin J. & Crespo M.B. 2019. Out of the Middle East: new phylogenetic insights in the genus Tamarix (Tamaricaceae). Journal of Systematics and Evolution 57: 488-507.).
The taxonomy of Iberian Tamarix is still a work in progress, and novelties and changes will come up in the future. It will be especially interesting to pay attention to the study of hybrids, which could likely occur between any of the Iberian species. The three species that are surely native (T. boveana, T. africana, and T. gallica, organized by the beginning of blooming periods), have different phenology that would prevent them from generalized hybridization events. However, the existence of late blooms can favour sporadic events between T. boveana and T. gallica, as it probably happened with T. × verae, and the blooms of T. africana and T. gallica can slightly overlap in spring. Surely, the rest of present species could be involved in hybridization processes. The occurrence of hybridization has been commented on in different works (Rusanov 1949Rusanov F.N. 1949. Sredniyeaziatskie Tamariksi. Tashkent. [Tamarisks of Central Asia].; Baum 1966Baum B.R. 1966. Monographic Revision of the genus Tamarix. Final research report for the USDA. Department of Botany. Hebrew University, Jerusalem.; Samadi & al. 2013Samadi N., Ghaffari S.M., Akhani H. 2013. Meiotic behaviour, karyotype analyses and pollen viability in species of Tamarix (Tamaricaceae). Willdenowia 43: 195-203.), and its importance and extension have been recently proven (Gaskin & Schaal; 2003Gaskin J.F. & Schaal B. 2003. Hybrid Tamarix widespread in U.S. invasion and undetected in native Asian range. Proceedings of the National Academy of Sciences 99: 11256-11259., Gaskin & Shafroth 2005Gaskin J.F. & Shafroth P.B. 2005. Hybridization of T. ramosissima and T. chinensis (saltcedars) with T. aphylla (athel) (Tamaricaceae) in the Southwestern USA determined from DNA sequence data. Madroño 52: 1-10.; Mayonde & al. 2015Mayonde S.G., Cron G.V., Gaskin J.F. & Byrne M.J. 2015. Evidence of Tamarix hybrids in South Africa, as inferred by nuclear ITS and plastid trnS-trnG DNA sequences. South African Journal of Botany 96: 122-131.). However, no formal descriptions of hybrids had been undertaken until now.