The Orchidaceae of Ruiz & Pavón ’ s “ Flora Peruviana et Chilensis ” . A taxonomic study

Pupulin, F. 2012. The Orchidaceae of Ruiz & Pavón’s “Flora Peruviana et Chilensis”. A taxonomic study. I. Anales Jard. Bot. Madrid 69(1):


INTRODUCTION
The background and aims of the Royal Botanical Expedition to Peru and Chile carried out by the Spanish monarchy in the second half of 18 th Century, as well as the main results in orchidology of the expedition, have been highlighted in the first part of this study (Pupulin, 2012).We presented there the figures of the illustrators sent by King Carlos III to the colonies of the New World and of the other artists who joined the Expedition during the almost forty years spent in South America by Ruiz and Pavón and their attachés.The critical study of the orchid iconography, the manuscripts and the collections brought back by the expeditionaries from tropical South America, proved to be fundamental for the correct identification and typification of the orchid taxa originally described by Ruiz andPavón (1794, 1798) and recorded in their documentary legacy.Whilst we previously discussed species arranged alphabetically from Acianthera Scheidw. to Maxillariella M.A. Blanco & Carnevali (Pupulin, 2012), in this contribution the discussion focuses on the interpretation of taxa from Onci dium Sw. to Zygopetalum Hook.At the light of the botanical illustrations prepared during the Expedition, each species is presented in this second part of the study with complete references to the nomenclatural types and their synonyms -and lectotyipified when required-, the unpublished ma nuscripts and exsiccata now kept at the Royal Botanical Garden (RJB), and to its mention in the the travel diaries by Ruiz (2007) Oncidium crocidipterum ranges from Venezuela and Colombia to Peru, where it inhabits cool montane wet forests between 2200 and 2800 m.Zelenko and Bermúdez (2008) offered a photograph of a Peruvian specimen of this species.The The Orchidaceae of Ruiz & Pavón's "Flora Peruviana et Chilensis". A taxonomic study. II Peruv. Chil. 1: 225. 1798.Type: Peru.Junín: "Habitat on nemoribus Tarmae ad Vitoc arce, unde Joannes Tafalla ad nos iconem ed descriptionem misit", J.J. Tafalla s.n.(lectotype, MA).Icones: AJB, Div.IV, 1235, drawing of type, selected here as the Lectotypus; tempera on paper by F. Pulgar, plant habit with flowers, detail of a flower and floral dissections.«Franc.coPulgar [signature] / 89 / 14 Maxillaria undatiflora [Tafalla]».Herbarium: No type specimens of this taxon are known to exist.
The type specimen of Maxillaria undatiflora (not conserved) was found at Vitoc, where Tafalla and Pulgar are certain to have collected in 1794, according to several specimens annotated by Tafalla and kept in MA.The illustrations prepared from the material found in this region are among the last prepared by F. Pulgar, whose appointment as draftsman of the expedition was officially terminated in March, 1797.According to the protologue, Ruiz and Pavón (1798) prepared their short diagnosis of M. undatiflora on the basis of the illustration and the description sent by Tafalla; it is probable that they never received an actual specimen of this species.In the absence of any know specimen associated with the protologue, the illustration by Pulgar is chosen as the lectotype.It shows the several distichous, large, imbricating sheaths -the upper ones foliaceous -which envelope the pseudobulb, the prominently 5-veined, oblanceolate, subacuminate leaves, the erect, paniculate, inflorescence with few-flowered, short lateral branches, and the flowers with yellow sepals and petals, blotched with brownish red, waved-undulated along the margins, and the white, 3-lobed lip, with the midlobe abruptly recurved, provided with a bilamellate, dentate callus, which distinguish O. undatiflorum.
The plate by Brunete illustrates a pendent species of Ornithidium without pseudobulbs, provided with a long, wiry rhizome and dense clusters of equitant (laterally flattened), fal-F.Pupulin plant illustrated by F. Pulgar could had been collected in the region of Huánuco, where he traveled with Tafalla to Muña, Pillao, Pozuzo and Chicoplaya between 1791 and 1796.
Conserved in the Archives of the RJB is a manuscript description of this species by J.A. Manzanilla (AJB, Div.IV, 4, 3, fol.83: «N.374 / L. 608»), where the original collecting location is indicated as «Habitat supra arbores Provintia Hua ya quil.Floret tempore pluvarum.Vulgo Flor del Spiritu Santo».The illustration in MA bears a manuscript number which corresponds to Manzanilla's description and was prepared in Ecuador, where O. planilabre is still relatively common in the tropical dry forests of the Pacific region, in the provinces of Guayas, El Oro and Manabí, from the sea level to about 300 meters.The species has been also recorded in Brazil (the type) and Peru.
O. planilabre is distinguished from other relatives in South America by elliptic, complanate, sulcate, subancipitous pseudobulbs, enclosed at the base by several foliaceous sheaths and diphyllous at apex, the inflorescence has, usually, few branches; the flowers have a relatively small, 3-lobed lip, with the lateral lobes subequal in size to the subrounded midlobe, and the column is almost wingless.(Ruiz & Pav.) Pupulin, comb.nov.

Fig. 34
Basionym: Maxillaria undatiflora Ruiz & Pav., Syst.Veg.Fl.According to a manuscript note on the actual specimen, the plant was collected at Cuchero, where the members of the expedition first collected between July and August of 1780, when their camp was attacked by Indians of Tupac Amaru II's party, and again in the first months of 1784.
The species illustrated by Pulgar, however, apparently differs from any other species of Otoglossum s.str.recorded in Peru (Zelenko & Bermúdez, 2009).While in the shape of the lip midlobe and general color it is somewhat similar to O. brachypterum (Rchb.f.) Garay & Dunst., the drawing in MA shows the lip provided with very narrow lateral lobes, a feature that does not agree with other Peruvian species of the genus.The Otoglossum painted by Pulgar strongly resembles an Ecuadorian plant illustrated in Dodson and Dodson (1984: pl. 975) as O. coronarium.As pointed out by Jenny (2010), this species is probably still undescribed.Unfortunately, no herbarium specimens of this taxon are kept in MA among the material of the Expedition.Ruiz (2007: 136;Ms. 12) refers to "Satyrium luteum" among the "plants discovered and described in the Province of Tarma and the frontiers of its Mountains" (id.130; Ms. 10), from June 1779 to the beginning of January of the next year.However, the holotype was collected at least six months later, during the stay of the Expedition in Huánuco and the excursion to Cuchero in July 1780 .

Pelexia pavonii
No original specimens of P. pavonii are conserved in MA.The manuscript, labeled by Pavón on the type sheet in G, clearly indicates that the specimen is an unicatum: «Exemplare unico / ex Gynandria / Orchys / Cochero" [Pavón] / herb.Pavon [alia manu]».It was received in Geneva with the Herbarium Barbey-Boissier, in which it was incorporated through the acquisition of specimens from Lambert's herbarium, which included specimens bought from the collections of the Oficina Botánica in Madrid.Reichenbach described the new species among the novelties from Ruiz and Pavón's Peruvian collections, which he had the opportunity to study in Boissier's herbarium (Reichenbach, 1856).
Probably endemic to Peru, P. pavonii may be recognized by the cylindrical, thick roots, the oblong-lanceolate, acute leaves, by an inflorescence slightly puberulent with acute bracts, and by the flowers which are provided with a short spur, the petals apically agglutinate to the dorsal sepal, and a ligulate-pandurate lip with the midlobe semiovate, acute, crenulated along the margins.For further synonymy of this taxon, see Schweinfurth (1951).S. boissierianum, quoting it among the species of Selenipedium section Acaulia coriifolia and including Cypripe dium boissierianum Rchb.f.("in Litt.") as a synonym (Reichenbach, 1854a: 3).Further on in the same volume (Reichenbach, 1858: 176-177, and Pl. 62), the author offered a comple te description and illustration of the species, where he expressly stated that he knew "only one specimen by Pavón", originally labeled "Cypripedium grandiflorum.Pillao.1787".The illustration, which shows the apex of the inflorescence, with two flowers in profile and details of the staminode, was also prepared from Pavón's specimen in the Boissier Herbarium.

Phragmipedium boissierianum
McCook (correction label, 1989) considered the two exsiccata of P. boissierianum conserved in MA as isotypes, but this hypothesis has no foundation.MA 810806 bears an original label by Tafalla, expressly stating that the plant was collected at Vitoc in 1794, and MA 810805 has the same number of the "Herbarium Peruvianum" («24/88»), likely being part of the same original collection, while the holotype was collected at Pillao seven years before.The Relación by Ruiz makes no reference to "Cypripedium grandiflorum" among the plants collected at Pillao (Ruiz, 2007: 301-304;Ms. 58-59).The beautiful plate by Francisco Pulgar was prepared from the specimen conserved in Madrid, and the number of the "Lámina" corresponds to that indicated on the label by Tafalla («170»).A possible isotype of P. boissierianum, sterile, with original label by Pavón («Cypripedium grandiflorum / del Peru»), is conserved at the British Museum (BM 26164, digital image!).This is probably the "second species, taken by Mathews out of the same collection, but […] too imperfect to be introduced here", which Lindley (1840) saw in Sir William Jackson Hooker's herbarium and mentioned in his description of Cypripedium caudatum (McCook, 1989).
Endemic to Peru [ranging to southern Ecuador if P. czerwiakowianum (Rchb.f.) Rolfe is considered as a synonym], P. bois sierianum grows in premontane to montane wet forests, along the eastern slopes of the Andes, from 400 to 1500 m, where it is mostly found in exposed road cuts or rocky slopes, or on the forest edges along streams.
A member of Phragmipedium section Lorifolia (Kraenzl.)Garay, characterized by the petals being distinctly longer than the sepals and fully grown at anthesis, the flowers produced successively, and the lip with a pair of hornlike outgrowths at both sides of the opening, P. boissierianum can be recognized by its green flowers, sometimes flushed with bronze, and the undulate crisped margins of the petals.According to Lindley (1840), the description of C. caudatum was prepared, on the basis of a mutilated flower, from a specimen of the herbarium of Ruiz and Pavón obtained in Lima by Mathews and sent to Sir William Jackson Hooker.The holotype at Kew does not have, unfortunately, any indication of the original collecting locality.On the type sheet it is mounted with another Peruvian specimen, collected by W. Davies in 1873 at Muña, one of the localities visited by Ruiz, Pavón, Brunete and Gálvez.From the diary of the Expedition, we know that the botanists observed populations of Cypripedium grandiflorum around Tarma, at Cuchero and Muña, and at least one of the specimens in MA was collected at Pillao.Ruiz (2007: 283-287;Ms. 53-54) prepared a description of C. grandiflorum during his stay in Muña, between August and September 1786, and, according to the diary, the species was probably illustrated at the same time (idem: 283; Ms. 53).It should be noted, however, that Ruiz apparently also employed the same name, Cypripedium grandiflorum, to refer to another species from Peru, eventually described by Reichenbach filius with the name Selenipedium boisserianum on the basis of a specimen by Ruiz and Pavón (Reichenbach, 1854a).A sterile specimen labelled «Cypripedium grandiflorum / del Peru» in Pavón's handwriting, now in G (26164!), most probably corresponds to P. boisserianum, and Schweinfurth includes Cypripedium grandiflorum among the manuscript names under the synonymy of P. boisserianum but not under that of P. caudatum (Schweinfurth, 1958: 17-19).

Phragmipedium
The plant of P. caudatum illustrated by Brunete is likely from the area of Muña, but I do not include it among the type materials of Cypripedium caudatum because we have no data about the holotype to support this choice.On the other hand, I am tempted to consider that the specimen found by Mathews in Lima, which eventually became the holotype of C. caudatum, was not part of the primary set of exsiccata of the Spanish botanists, or they would not have left it in Peru.
Another sheet with a single flower of Phragmipedium caudatum, annotated by Pavón himself as «Cypripedium grandiflorum / del Peru / Flor», is kept in BM (26160!), but, according to a manuscript label («Peru.Herb: Pavon»), this specimen was probably one of the plants sold by Pavón and acquired by the British Museum with the Lambert herbarium.In 1989, L.M. McCook annotated the specimen as Isotype (correction label, 1989;McCook, 1989) but with no indication of location or collecting date to support this decision.The Barbey-Boissier Herbarium in G also conserves a specimen of P. caudatum (G 169103!) that was originally part of the materials kept at the Oficina Botánica, obtained by Geneva through the Lambert herbarium.It is annotated by Reichenbach filius as "Selenipedium caudatum" and it was surely part of Ruiz and Pavón's primary set of plants: like the specimens in MA, it includes all the vegetative parts and the inflorescence with a flower.McCook (1989McCook ( , 1998) ) included the sheet in G and those in MA among the isotypes of P. caudatum, but there is no convincing evidence about their status as types.
In his diary, Ruiz makes no mention of any collection of C. grandiflorum at Pillao, where the members of the Expedition herborized from August to November, 1787.The illustration by Brunete was surely done before the journey of Ruiz, Pavón and Tafalla to Pillao because the artist died in Pasco on May 14, 1787, and his last works were prepared not later than November 1786, when he left Huánuco for Lima.Ruiz recorded C. grandiflorum from the mountains of Tarma (Ruiz, 2007: 136;Ms. 12), where the group collected in 1779; from Cuchero (idem: 165; Ms. 21), where the botanists and the crafstmen worked in July and August, 1780; and from the vicinity of Muña where, according to the diary (idem: 287; Ms. 55), the species was described and illustrated between August and November 1786.In the latter note, Ruiz recorded the local name of C. grandiflorum as "Rima-Rima" (ibid.), a name that is also referred to Masdevallia uniflora (idem: 136; Ms. 12).
As understood today, after the removal of Central American populations under Phragmipedium humboldtii (Warsz.)J.T. Atwood & Dressler, P. caudatum is apparently endemic to Peru, where it has been recorded in Cuzco, Huánuco, and Puno, as a terrestrial on fully exposed grassy slopes, more rarely as a lithophyte or epiphyte, at elevations of 1500-2500 m.
This large plant is characterized by ligulate, leathery, distichous leaves, an erect inflorescence subequal to the leaves, with 2-4 flowers open simultaneously.The flowers, with narrow petals that continue to grow after anthesis, reaching over 70 cm in length, are unmistakable.(Ruiz & Pav.)  Humboldtia cordata is the first described taxon of a large, frequent and variable species-complex, distributed along all the Andes from Venezuela to Peru and Bolivia.It can be recognized by the large, horizontal, broadly ovate, deeply cordate leaves, the one to several flowers produced simultaneously with the synsepal a little broader than the dorsal sepal, the petals minutely denticulate, and the lip ovate provided with a small glenion.In his systematic treatment of Acronia, Luer (2005) recognizes three subspecies of A. cordata, of which subsp.rhopalocarpa (Schltr.)Luer has an obovate (vs.ellipticovate) dorsal sepal, distinctly longer than the synsepal; subsp.trachysepala (Kraenzl.)Luer has ciliate sepals and petals.

Pleurothallis cordata
In its broad acception, Pleurothallis cordata occupies a broad range of ecological zones, from tropical wet forest at 500 m, to cool, montane cloud forests up to elevations of 3400 m, where the plants grow epiphytically or as terrestrials on steep embankments.In Peru, it has been recorded in Amazonas, Cajamarca, Cusco, Huánuco, Pasco, Puno, and San Mar tín, where populations are found in premontane to montane wet forests from 1000 to over 3200 m.
According to the Relación by Ruiz, Humboldtia cordata was described and illustrated on the basis of material collected around Muña (Ruiz & Pavón, 1798: 234), when the Expeditionaries stayed there in August-September of 1876 (Ruiz, 2007: 287;Ms. 54-55).However, the only sheet in MA annotated with the name "Humboltia [sic] cordata" in Ruiz's handwriting, was ostensibly collected at Pillao, an area that Ruiz, Pavón and Tafalla visited only in August 1787, and where they stayed until the end of September of the same year.For this reason the specimen annotated by Ruiz, which would be logical to regard as the holotype, cannot be considered as such, and all the other materials that are part of the original collections of the Expedition cannot be assigned to any specific area.Other original exsiccata of Humboldtia cordata are kept in the Humboldt herbarium in Berlin (digital image!), in BM (digital image!), and F (digital image!).(Ruiz & Pav.)   Pleurothallis revoluta has an erect, stout, apically grooved ramicaul, enclosed at the base by tubular, inflated sheaths; a lanceolate-elliptic, subcoriaceous leaf, narrowing at the base into a conduplicate sinus; one to several simultaneous inflorescences, longer than the leaf, carrying numerous, non-resupinate flowers successively opened, the whitish flowers provided with a cymbiform synsepal and narrow, linear-oblong petals, variously thickened at apex.These features are diagnostic of this species.According to the systematic treatment by Luer (1999), the size and color of the flower of P. revoluta are variable, but they are commonly translucent green and finely spotted with purple.See Luer (1999) for a complete list of suggested synonyms of the species.

Pleurothallis revoluta
Pleurothallis revoluta ranges from Trinidad and Venezuela to Colombia, Ecuador, Peru, and Bolivia, where it has been found in wet montane wet forests at elevations of 1800-2000 m.In his Relación, Ruiz recorded that Humboldtia revoluta was described and illustrated while the Expedition was in Muña, in August-September of 1876 (Ruiz, 2007: 287;Ms. 55).Ponthieva fertilis are terrestrial, variable plants, which can be over 50 cm tall (but usually smaller), with fasciculate, slendertuberous roots and sessile or short-petiolate leaves both basal and cauline.They have a dense, many-flowered, tomentose in-florescence, floral bracts shorter than the ovary, and small, white, non-resupinate, pubescent flowers, provided with a concave-conduplicate, proximally scaccate, distally 3-lobed lip.

Ponthieva fertilis
Ponthieva fertilis has been recorded in montane wet forests in Venezuela (?), Colombia, Ecuador, Peru, and Bolivia, up to 300 m of elevation.In Peru, populations have been found in Ayacucho, Cuzco, Huánuco, Junín, and Loreto, where the lances grow in open woods and dense evergreen forest, often on steep banks, at 500 to 2500 m. 60.Psygmorchis glossomystax (Rchb.f.) Dodson & Dressler, Phytologia 24: 288. 1972 The sterile specimen mounted on MA 810790, collected by Tafalla at Chicoplaya in 1897 («Orchys N. 10»), is probably also referable to this species.It was described in detail in a manuscript kept at the Archives of the RJB, «N.10. / Gynadria Diandria / Orchys?an Ophrys?/ […]» (AJB, Div.IV, 4, 3, fol.40).On the original label, it is compared to another collection by Tafalla («It has strong affinity with that of N.[umber] and L.[ámina = Plate] 366 »), a specimen of Psygmorchis pumilio that was illustrated by J.G. Rivera (AJB, Div.IV, 1268, see hereafter).M. Rodríguez noted on a correction label (1984) that the specimen is probably referable to a species of the genus Notylia Lindl.[= Macroclinium Barb.Rodr.], but in the latter genus the leaves are distinctly articulated with the basal sheaths that envelop the pseudobulb, while in the ebulbose P. glossomystax there are no basal sheaths.
The very small plants, consisting of a flabelliform cluster of equitant leaves, the yellow flowers with brownish red spots on the petals and the base of the lip, and the disc of the lip with 2 pairs of lamellae terminating in deep fringes, are diagnostic of the species.Widespread and locally abundant, P. glossomystax is distributed in most of South America, from Venezuela to Brazil and from Colombia to Bolivia along the Andes.In Peru, it has been recorded in the provinces of Cuzco, Junín, Loreto, Madre de Dios, and San Martín, at elevations ranging from 300 to 900 m; it is common in old coffee plantations and on Psidium guayava L. trees.apex of the leaf; its flowers are medium to relatively large (dorsal sepal 25-35 mm long); the sysnsepal is shortly bifid; the lip variably verrucose and spotted as the synsepal.However, as admitted by Luer & Escobar (1996), positive identification of many specimens is not possible.The species has been known under its synonym, R. maculata Lindl.( 1846), which is still in use.For a complete list of synonyms of R. contorta, see Luer & Escobar (1996).According to Ruiz's diary of the Expedition, Humboldtia contorta was described and illustrated during the stay in Muña in August-September of 1876 (Ruiz, 2007: 287;Ms. 55).According to Ruiz (2007: 281;Ms. 53), the original description of R. lanceolata was destroyed during the fire of Macora of August 1785, and it was redone during the journey of the expedition in Huánuco in 1785.The holotype in MA (810827) has two labels, one manuscript by Ruiz («Rodriguezia ensiformis») and the other, handwritten by Tafalla, indicating the collecting location as Chicoplaya, along the Río Monzón in central Huánuco department.It is obvious that the description of R. ensiformis makes no reference to the specimen of Tafalla, which was collected when the Systema had gone to press, in a region that Ruiz and Pavón themselves never visited.Fortunately, Tafalla's label refers to an illustration by J.G. Rivera (N.326), which is still in existence in MA and has the same name, «Orchys tripetala», annotated on the label.However, the plate by Rivera depicts Rodriguezia strobelii Garay (see discussion under this entry below), a species with cespitose habit and with leaves much stouter than those of R. ensiformis.The specimens in MA, with their rhizomatous habit and the narrow, ligular leaves correspond to the illustration of the type prepared by Brunete, and Ruiz original mansuscript (Div.IV, leg.4, 3, fol.4: «Gynandria Diandria 156 / Rodriguezia ensiformis ic.140») explicitly refers to it.

Rodriguezia ensiformis
A poorly known species, R. ensiformis is apparently endemic to Peru.Uncommon but locally abundant from Mexico, through Central America, to Venezuela, French Guyana, Surinam, and Brazil, and from Colombia to Peru along the Andes, P. pumilio inhabits tropical to premontane, warm forests at elevations of 200-1500 m.

Rodriguezia lanceolata
The miniature plant with a fan-shaped spread of leaves with 1-2 axillary, erect to arching inflorescences, producing 2 to 3 flowers per inflorescence, singly in succession, and the concolorous yellow flowers with an obtriangular, thick callus, apically fimbriate distinguish the species.When compared to P. glossomystax, the plants of P. pumilio have broader leaves, the flowers are smaller and the apical callus is single, fimbriate (vs. in pair, deeply fringed in P. glossomystax).
At the Archives of the RJB is kept a full description of this plant with the title «L.366./ Gynadria Diandria / Ophrys / […]» (AJB, Div.IV, 4, 3, fol.45).(Ruiz & Pav.)  Belonging to the Subgenus Restrepia, Section Restrepia, R. contorta is a variable and widely distributed species, ranging from Venezuela to Colombia, Ecuador and Peru.Frequently, in its native habitats, it has been recorded growing epiphytical in wet submontane and wet montane forests, at 1100-3200 m of elevation.

Restrepia contorta
In their systematic revison of Restrepia, Luer and Escobar (1996) treated R. contorta as a variable species-complex, grading into the smaller R. elegans and the larger R. guttulata.The peduncle of R. contorta bears the flower near or beyond the    The lectotype material conserved at MA is sterile and it bears the manuscript, intended name «Orchys [sic] dependens».However, the number 175 assigned to the specimen, as well as the colleting locality of Vitoc noted on the original label, unequivocally correspond to the number cited in Pulgar's illustration of R. lanceolata.According to the original label, the plant was collected in 1794, six years after Ruiz and Pavón sailed home from Peru, and the drawing by Pulgar was likely prepared in the same date.In his diary, Ruiz refers that the original description of R. lanceolata was destroyed at Macora, and that it was prepared another time in Huánuco in 1785 (Ruiz, 2007: 281;Ms: 53).This may leave some concern about the actual status of the specimen at MA.However, it is sure that Ruiz and Pavón received it, together with the corresponding drawing, before the publication of the Systema in 1898.Tafalla and Pulgar sent specimens and 165 drawings and descriptions in 1793, and again they sent materials from Huánuco and Tarma in 1795 (Steele, 1964: 270-271).As the shipment of the boxes required almost one year coming to Spain, the specimen collected at Vitoc and the relative drawing could have reached the hands of Ruiz in 1786, and both are therefore eligible for typyfication.The Archives of RJB kept two manuscript descriptions referred by Ruiz to «Rodriguezia lanceolata», the first prepared by the leading botanist on the basis of a plant collected before 1788 "in umbrosis Cuchero montibus" (AJB, Div.IV, leg.4, 3, fol.5: «Gynandria Diandria 157 / Rodriguezia lanceolata s.ic.»), and the other written by Tafalla (AJB, Div.IV, leg.4, 3, fol.3: «L.175 Gynandria Diandria / Orchys [deleted] Rodriguezia lanceolata [Ruiz]»).Ruiz not only annotated Tafalla's description with the name «Rodriguezia lanceolata», but he also emended his original description to include morphological notes taken from the manuscript describing the plant from Vitoc.He added an improved description of the vegetative parts («bulbi obovati […] compressi, folio unico terminati / Scapi axillares solitarii dependentes, foliis breviorers») literally copied from the verso of Tafalla's manuscript, and changed the type locality according the field note provided by Tafalla.There are no doubts that the description of the species was therefore prepared using both the plants collected at Cuchero and at Vitoc.While MA 810828, choosen as the lectotype, is sterile, the drawing by Pulgar well illustrates the habit with flowers and includes accurate dissections of the flower.
The British Museum hosts another specimen (BM 74440!), annotated in Pavón's handwriting «Rodriguezia / Gen. nov.», with a manuscript label recording that the specimen was part of the herbarium of Pavón (originally at the "Oficina Botánica" in Madrid).The plant is sterile, and it was tentatively annotatd as Isotype, but it has no indication of locality and date, and its status as type is dubious.Garay, Canad. J. Bot. 34: 258. 1956.According to the manuscript description of this species by Tafalla, kept in the Archives of RJB (AJB, Div.IV, 4, 3)."Orchys tripetala" was collected in the «Sylvis Chicoplayae supra Arbores».A herbarium label by Tafalla «Orchys tripetala./ F.P.c.l.Nº 326, / Ex Chicoplaya.A o 97») is affixed to the holotype of Rodriguezia ensiformis (MA 810827), but the specimen does not correspond, morphologically, to the illustration by Rivera.José Gabriel Rivera was hired to join Tafalla, J.A. Manzanilla and F. Pulgar and to be trained in botanical illustration only in October, 1796 (Pulgar's appointment was officially terminated on March 16, 1797).In 1797 and 1798 Tafalla, J.A. Manzanilla and J.G. Rivera visited San Antonio de Playa Grande, Chicoplaya and the Monzón mountains.During this time, Rivera prepared 90 illustrations (Tafalla, 1989).On May 11, 1799, the trio shipped for Guayaquil, only returning to Lima ten years later.

Rodriguezia strobelii
Rodriguezia strobelii is known from Ecuador and Peru, where it inhabits coastal dry tropical forests and premontane forests from sea level to 1300 m.The faintly fragrant flowers, white to pale rose finely speckled and suffused with purple, distinguish the species.Widely distributed in the Neotropics, from El Salvador, through Central America, the Windwards, Trinidad and Tobago, to most of South America (Venezuela to Brazil and Colombia to Bolivia), S. acaulis is found at elevations of 100 to almost 3000 m, where it grows as a terrestrial in wet tropical to cool montane forests.In Peru, it has been recorded in the provinces of Amazonas, Huánuco, Junín, Loreto, and San Martin, from 100 to 1800 m.

Sarcoglottis acaulis
The basal rosette of obovate-elliptic leaves with a distinct, elongate petiole, and the erect, pubescent inflorescence with long, acuminate bracts that exceed the ovary, distinguish this variable species.
According to Ruiz's journal, Satyrium bicolor was described and illustrated while the Expedition was in Pozuzo, in September, 1784 (Ruiz, 2007: 256;Ms. 44).For other synonyms of this species, see Garay (1978b), and Brako and Zarucchi (1993).Sauroglossum corymbosum is only known in Peru and Bolivia.In Peru, populations are found in cool regions in the provinces of Cusco and Junín, at 2500-2600 m.The plants grow terrestrially in crevices with poor lateritic soils in low, semi-xerophytic brush and grass (Dodson & Bennett, 1989).

Sauroglossum corymbosum
The type, in Lindley's herbarium at Kew, was obtained through the acquisition of Hooker of Lambert's materials.Apparently, no isotypes were conserved, and none of the sheet in MA is attributable to species of the genus Sauroglossum.The plate painted by Francisco Pulgar was probably prepared from the only known collection of this species by the members of the Expedition, and I consider it an illustration of the type.
The terminal, corymbose inflorescence, provided with distant, tubular, acuminate bracts, and the pure golden yellow flowers, the lip crenate at the margin are diagnostic of the species.This species is distinguished by a elongate, ascending rhizome with widely separated, compressed, rugose, monophyllous pseudobulbs; an erect, single-flowered inflorescence that rises from a mature pseudobulb, enveloped by distichous sheaths; a trigonous ovary; and greenish yellow flowers, with the lip orange-yellow, provided with a 3-lobed lip, denticulate along the midlobe and on the apical margin of the lateral lobes.Schweinfurth (1970) and Vásquez C. & Dodson (1982) included Maxillaria trigona C. Schweinf.[= Sauvetrea trigona (C.Schweinf.)Szlach.] in synonymy under M. alpestris.However, in the latter species, the midlobe of the lip has entire margins and the lateral lobes are striped with reddish-brown along the veins.Blanco & al. (2007) considered that the genus Sauvetrea needs a thorough taxonomic revision, and I favor maintaining the two taxa as distinct pending further studies in the group.For a complete list of possible synonyms of S. alpestris, see Vásquez & Dodson (1982).

Sauvetrea alpestris
Sauvetrea alpestris has been recorded in Venezuela, Colombia, Ecuador, Bolivia and Peru.In Peru, it is a widespread but uncommon species in Amazonas, Cajamarca, Cusco, Pasco, and Puno provinces, where populations are found in premontane and montane wet forests at 1500 to almost 3000 m of elevation.Ruiz and Pavón's diagnosis of Bletia uniflora ("B.bulbis subrotundis compressiusculis, foliis linearibus carinatis, scapis radicalibus unifloribus") was not detailed enough to allow an understanding of the generic placement of this species, and in the absence of any original specimen annotated by the authors with this name, the concept has remained obscure since its description.However, conserved among the illustrations prepared by Pulgar on the material collected by Tafalla and J.A. Manzanilla at Vitoc, in the province of Tarma, is a drawing of a species unmistakably referable to the genus Sauvetrea, which bears the manuscript name of «Bletia uniflora» and the number «169».The holotype in MA bears the same number and, although sterile, shows the typical habit of the species.Another herbarium specimen with the same number was still conserved in Lima in 1832, when Andrew Mathews studied it.Like the holotype, it had been collected at Vitoc, as stated in the prologue of Bletia uniflora.

Sauvetrea uniflora (Ruiz
The drawing of the type by F. Pulgar clearly shows the plant habit, the yellow flowers and the lip without a prominent callus, which is diagnostic of the species in the genus Sauvetrea.Lindley (1845a) described M. laevilabris on the basis of a drawing sent by A. Mathews from Lima, which was probably traced from one of the specimens originally collected at Vitoc.The drawing at Kew shows the caespitose habit of the plant, with the characteristically falcate, distichously alternate, inflate-compressed, imbricating bracts of the inflorescence, and a detail of the ecallose lip.The manuscript note associated with the drawing indicates that the specimen was collected at Vitoc in 1794, «ex herb.R. et P. in Lima conservato».The number of the specimen in the system of the Flora Peruviana, «169», corresponds to that noted by Francisco Pulgar in his drawing of Bletia uniflora.
Maxillaria piestopus, based on a Costa Rican specimen collected by A. Tonduz in 1913, is apparently very close to S. uniflora in the plant habit, color of the flowers, and the lip without a prominent callus.The photograph in AMES (40549!) of the holotype destroyed in Berlin, with the original analytical drawing by Schlechter, shows a triquetrous ovary and a 3-lobed, ecallose lip, which are almost indistinguishable from those illustrated by Pulgar.I have not seen the type of Maxillaria koehleri Schltr., also described from Peru from a specimen collected by the brothers Köhler in 1920, which Blanco and co-authors (2007) included under the synonymy of Sauvetrea laevilabris.
Sauvetrea uniflora ranges at least from Ecuador to Peru and Bolivia (up to Costa Rica to the North, if M. piestopus is considered a synonym), where it is found growing epiphytically in wet montane forests, at 800-2100 m.The type material in MA includes three sheets, one of which is annotated in Ruiz's handwriting as «Sobralia biflora».The three specimens are sterile, and they bear an old label of the "Herbarium Horti Botanici Matritensi", with Mansfeld's determinations, indicating number «4/62».Even though these numbers were assigned at the herbarium, and have not to be understood as field numbers by Ruiz and Pavón (who do not used them), they, nevertheless, give evidence that the three specimens were part of the same original gathering.
The species ranges from Colombia to Peru and Brazil.In Peru, it apparently seems restricted to the warm, tropical forest of Huánuco and Junín, where it grows as an epiphyte between 200 and 450 m.The loosely leaved stems to about one meter tall, with large, ovate-lanceolate, thin leaves, the pubescent-scabridous sheaths, the terminal, sessile, cone-like, 2-flowered inflorescence, and the campanulate, lilac flowers with obovate petals and retuse lip provided with parallele keels distinguish the species.The plate by Pulgar and the sheet in MA have the same number, and correspond to a plant collected by J.J. Tafalla in 1895.

Sobralia
These are tall plants (up to 2 meters), with a relatively short, lateral, many-flowered inflorescence and small, bright rose-purple flowers with the lip fringed apically.Sobralia ciliata is known from Venezuela, Ecuador, Bolivia and Peru; in the latter country it inhabits montane wet forests at 1700-2200 m.A giant sized species, with stems that can reach 5 m in length, with ovate-lanceolate, leathery leaves, tinged with purple on the back, S. dichotoma is distinguished by the lateral, dichotomously branched, many-flowered, successive inflorescences, the fleshy, long lasting, strongly fragrant red-brown flowers, edged with lighter red and violet, and the laciniate callus of the lip.

Sobralia dichotoma
In his diary, Ruiz refers to S. dichotoma on several pages.It is first mentioned among the reach orchid collections made in the mountains of Tarma in the second half of 1779 (Ruiz, 2007: 136;Ms. 12), and recorded with other plants discovered at Cuchero in July, 1780 (idem: 165;Ms. 20).The description of S. dichotoma was prepared on the basis of at least three different collections recorded in Ruiz's manuscript.The first description was done in Chinchao, where Ruiz and the illustrators worked during the month of August 1780 [idem: 168;Ms. 21(a)]; the second in Pozuzo, between July and November 1784 (idem: 256; Ms. 44); and the third in Muña in July-September 1786(idem 2007: 287;Ms. 54).According to Ruiz, the illustration was realized in Muña, and the botanist also noted the vernacular name of S. dichotoma, "Tahuetahue", noting that "its flowers are beautiful for their size, color, and fragrance" (ibid.).Other vernacular names used in the Andean region for this species are "Flor de paraíso" (bird of Paradise), "Inquil", and "Monte azucen".Poepp. & Endl., Nov. Gen. Sp. Pl. 1: 54, t. 93. 1836, non Lindl., Fol. Orchid. 5 (Sobralia) The species has been recorded in Ecuador, Colombia, Peru and Bolivia, along the eastern slopes of the Andes, but also in the coastal and Amazonian regions of Ecuador.It grows as a terrestrial on steep, brushy and grassy embankments in wet tropical to montane forests, from sea level to over 3000 m.In Peru, populations of S. rosea are found in the provinces of Amazonas, Cajamarca, Huánuco, Junín, and San Martín, at elevations between 500 and 2200 m.

Sobralia rosea
The very long stems, up to 3 m tall, the narrowly lanceolate, long-acuminate leaves, the terminal, fractiflex, racemose inflorescence with large, cymbiform floral bracts, and the large, fragrant, successive, white to rose flowers with a darker, crispedundulate lip marked with purple distinguish the species.
The illustrations by F. Pulgar may have been prepared during the trip by Tafalla and J.A. Manzanilla to the region of Huánuco in 1787, or in Ecuador, during the journey of the artist to that country from 1799 to 1809.The sterility of the holotype of Humboldtia acutiflora in MA prevented previous researchers from correctly understanding the generic placement of this taxon.The illustration by Isidro Gálvez clearly shows the lax inflorescence, the bilabiate flowers, not completely spreading, and the acute-subacuminate synsepal.which are characteristics of the Specklinia grobyipicta complex (sensu Luer, 2006), to which this species belongs.The group is quite difficult taxonomically, having specific circumscriptions that partially overlap and a multitude of intermediate forms between the recognized species.Humboldtia acutiflora could be the first available name for Specklinia picta (Lindl.)Pridgeon & M.W. Chase, a species that can be recognized within the complex by the narrowly acute to acuminate synsepal (Luer, 2006).
The generic circumscription of Specklinia Lindl.has been subject of an open debate (see Pridgeon & al., 2001;Pridgeon & Chase, 2001;Luer, 2002Luer, , 2006)), but the characteristic features of S. acutiflora place it in the core group of Specklinia species.On this most of the authors agree.(Ruiz & Pav.)The holotype in MA comprises seven different plants, one of which (noted with the letter "A" on the sheet) was included in the herbarium in 1828.Several students annotated the sheet, doubting the common identity of the mounted specimens, but the species of Stelis are quite variable vegetatively so there is no reason to reject a priori the original identifications.A fragment of the holotype, consisting of an incomplete leaf with ramicaul and two sterile inflorescences is kept at the herbarium of the Field Museum in Chicago (F (40668F, digital image!), where it was received through the Real Jardín Botánico of Madrid.An isotype, part of the Humboldt collection, is in Berlin (digital image!).Two specimens are conserved, in P, originally from the Peruvian collections by Dombey, annotated as isotypes (P 489351 and 489352, digital images!).Schweinfurth (1958Schweinfurth ( , 1970) ) considered Stelis bicallosa Schltr., also from Peru, as a synonym of S. parviflora, but I have no direct knowledge of the type material.However, in the drawing of S. bicallosa published by Duque (2008: 61), the lip is shown as obtrapezoidal in outline (vs.ovate) and the petals have a distinct, rounded apicule at apex (vs.broadly obtuse).Garay (1979) illustrated the flower of S. parviflora, which can be recognized by the glabrous flowers with free, 3-veined sepals, the transversely rectangular petals and the broadly ovatesubrhombic lip, provided with two mammillate calli forming a narrow channel under the column.The illustration provided by Duque (2008) differs in having a long-apiculate lip.

Stelis purpurea
An isotype of H. acutiflora is kept in the Willdenow herbarium in Berlin (B-W-16901-010, digital image!).MA 810810 (sterile!) is annotated by Mansfeld as part of the original material of Humboldtia acutiflora.However, the specimens on this sheet are much larger than those mounted on the holotype sheet, and they also differ from the type in the size and shape of the caulinary bracts.I do not consider this an isotype.
According to the Relación by Ruiz, the original description of H. acutiflora was probably among those lost during the Macora fire in August, 1785; a new description was prepared while the Expedition was in Huánuco in 1785-86 (Ruiz, 2007: 281;Ms. 52).(Ruiz & Pav.)  Stelis oblonga is known from Colombia to Ecuador and Peru, where populations are found in premontane and montane wet forests from 600 to almost 4000 m.The species is apparently quite variable vegetatively, with the leaves broad and elliptic-oblong.The multiple inflorescences as long as or longer than the leaves, the small, papillose flower and the lip with truncate, abruptly acuminate-apiculate apex distinguish the species.

Stelis oblonga
For a complete synonymy of the species, see the systematic treatment by Luer (2009).In his monograph of the genus Stelis, however, Duque (2008) does not agree with such a view, noting that the habit of S. oblonga is entirely different from that of S. apiculata Schltr., S. floribunda Kunth, and S. insignis Ames.
According to Ruiz's journal, the original description and illustration of S. oblonga were prepared in Muña in August-September, 1786 (Ruiz, 2007: 287;Ms. 55).Ruiz' manuscript description is kept at the of the RJB, Div.IV, leg.4, 3, fol.115: «Gynandria Diandria / Humboltia oblonga ic.163»).Icona 27, Figurae 1-3, 4,7( Stelis purpurea is a common species along the Andean chain from Colombia to Bolivia, where populations are found growing epiphytically or frequently terrestrially on moss covered rock and clay embankments, in premontane wet to montane cool, cloud forest, between 1400 and 3500 m.In Peru, it has been recorded in the provinces of Amazonas, Cajamarca, Huánuco, Junín, and San Martín, in montane wet forest at elevations of 2000 to 2500 m.Garay and Sweet (1972) selected Humboldtia purpurea as the lectotype of the genus Humboldtia Ruiz & Pav. (non Vahl 1794, Fabaceae, nom. rej.), originally published by Ruiz and Pavón (1794) as Humboltia and corrected in their Systema of 1798.It is also the lectotype of Stelis sect.Humboldtia (Ruiz & Pav.) Pers., a large group of species distinguished by the bilabiate flowers with a synsepal formed by connation of the lateral sepals.Among them, Stelis pupurea may be recognized by the usually robust plant with many-flowered racemes that far exceed the elliptic leaves, with long floral bracts, 5-to 7-veined dorsal sepal and the lateral sepals connate into a concave synsepal.
In creating the genus Xenosia for Pleurothallid plants with densely ascending habit provided with bundles of short ramicauls, Luer (2004) transferred to his new genus Humboldtia spiralis, but successively (Luer, 2006) he included Xenosia spiralis under the synonymy of X. macrorhiza (Lindl.)Luer.This move, however, is contrary to the rule of priority, Humboldtia spiralis Ruiz & Pav. (1798) being older than the basionym of X. macrorhiza, Pleurothallis macrorhiza Lindl.( 1834).I agree with the generic placement suggested by Luer in 2004, but the color of the flowers of X. spiralis, as annotated on the original label ("yellow, spotted with sulphur yellow"), differs from that recorded from the other species recognized by Luer in his systematic treatment of Xenosia (Luer, 2006).Xenosia spiralis may perhaps represent the third valid species of the genus.The terrestrial plant over 60 cm tall, with fascicled, tuberous roots, the basally imbricating, oblong-lanceolate, acute leaves, narrowed below to a long-sheathing base, the shortly pubescent stem, the subdense, many-flowered inflorescence, and the small, yellowish-green, tubular-recurved flowers with the lip provided with membranous, denticulate margins distinguish the species.
Stenoptera peruviana is known from Colombia, Ecuador, and Peru.In Peru, it has been recorded in the provinces of Amazonas, Cajamarca, Huánuco, Junín, and Loreto, where it grows in open woods, in montane wet forests at 1300-3200 m.For a complete synonymy of S. peruviana, see the treatments by Schweinfurth (1958) and Garay (1978b), and the checklist of Peruvian plants by Brako and Zarucchi (1993).(Ruiz & Pav.)The short inflorescences (to 17 cm) and the fragrant flowers, with the finely laciniate the lip provided with a 5-keeld callus, distinguish the species.Poepp. & Endl., Nov. Gen. Sp. Pl. Nov. Gen. Sp. Pl. 2: 11, pl. 115. 1836.The plant provided with rudimentary pseudobulbs and subcoriaceous leaves, and the flowers with white tepals, variously spotted and blotched with purple, and a long labellar spur, are diagnostic of the species (Pupulin, 1995).The plate by Isidro Gálvez is probably the first illustration of T. pulchrum (another was painted by one of the drafstams of Mutis' expedition to New Grenada; see Mutis, 2000), a species quite common along the mid-elevation regions of the Andes from Venezuela to Bolivia.In his diary, Ruiz (2007: 281;Ms: 53) quote O. punctata among the species of which the original description was lost during the Macora fire.

Trichocentrum pulchrum
Ortiz y Valdivieso (2000) quoted a specimen of T. pulchrum among the exsiccata of Ruiz and Pavón kept in MA, but I was unable to locate it in the collection.Oakeley (2008) refers to Ida [Sudamerlycaste] ciliata as a lost species, structurally similar to Ida [Sudamerlycaste] fragrans but mainly distinguished from it by the color of the flowers (pale cream vs. pale yellow-green).However, this is probably the result of an artifact.In the unpublished description of Maxillaria ciliata by Ruiz (folio manuscript, recto, headed «160 / Gynandria Diandria / Maxillaria ciliata / […]», AJB, Div.IV, leg.4, 3, fol.8), the author explicitly refers to the tepals as yellow («Corolla flava»).On the other hand, in both the plates by F. Pulgar kept in MA, the flowers and the floral dissections of Maxillaria cilata are not colored, i.e. they are left with the basic rendering in black ink or tempera.In AJB, Div.IV, 1238, the fertile inflorescences are also not colored, while the pseudobulbs and leaves are completely painted and a first layer of color is applied to the lateral, sterile inflorescences.Oakeley probably intended to designate the plate 1238 as the species' lectotype, but the text of his proposal (Oakeley, 2008: 212) is not in agreement with the requirements by the ICBN (art. 7.11, Mc-Neill & al., 2006), and a formal typification is required to fulfill the mandatory rules of the Code.

Trichoceros
Two different sheets in MA have been annotated as type material of Maxillaria ciliata.The number «25/28» was originally assigned to both on the labels corresponding to the Herbarium Peruvianum of Ruiz and Pavón.The first sheet (MA 810771), which bears two original labels by Ruiz («Arethusa?ciliata [crossed] / Maxillaria / ciliata» [Ruiz]; «Serapias?an Arethusa?[crossed] / Maxillaria / ciliata»), includes mixed specimens, none of which is apparently referable to the concept of Maxillaria ciliata.The top left flower corresponds to Tafalla's label («Gynandr.Diand./ Orchys / F. P. c. l.Nº 377./ Ex Chicop.A.º 95.») and to the illustration by J.G. Rivera (AJB, Div.IV, 1255, «J.G.R. del / 377 / Orchis»), and it is referable to Lycaste macrophylla.A second  A quite poorly known species, V. hamata is a member of the V. pompona group (Soto Arenas & Cribb, 2009).The holotype in B was destroyed in 1943, but in the photograph of the type in AMES, the original label clearly indicates Nº 341, the same as Rivera's illustration.The plate in MA well illustrates the trilobed, emarginate lip, with a penicillate callus and a thickened axial cushion in the apical third of the lip.Even though the original collection team of V. hamata is usually recorded as Ruiz and Pavón (i.e., Schweinfurth, 1958) or Pavón (i.e., Soto Arenas & Cribb, 2009), the type specimens were collected in 1798, ten years after the departure of the Spanish botanists for Cadiz.The signature by Pavón on the sheet labels in B and G was probably affixed when he sold part of collections of the Oficina Botánica to Lambert from 1816 to 1824.
The diary by Ruiz includes two references to species of the genus Vanilla, but both were described at least ten years before the group guided by Tafalla collected V. hamata (in 1795, according to the sheet destroyed in Berlin) and V. ruiziana in 1798.During the journey of the Expedition in Cuchero in July 1780, Ruiz noted that "the Indians are used to bringing the fruits [of "Vanilla officinalis"] to sell at Huánuco" (Ruiz, 2007: 164;Ms. 21).Another species of Vanilla, "Vanilla volubilis V. Vaynilla", was collected at Pozuzo (Ruiz, 2007: 256 The plant illustrated by Isidro Gálvez belongs to the Vanilla pompona group (Vanilla subgen.Xanata sect.Xanata), characterized by xerophytic plants with thick stem and very fleshy leaves, and the fruit trigonous.In their synopsis of Vanilla, Soto Arenas and Cribb (2010) treated V. grandiflora at the specific rank, while Soto Arenas and Dressler (2010) considered it a subspecific form of V. pompona Schiede.Being geographically limited to the Central American taxa of Vanilla, the latter contribution does not include specific citations of South American specimens, but the authors express some doubts about the real identity of the Andean taxa.
Broadly distributed from Trinidad & Tobago, Venezuela, Guyana and Brazil, to Peru, in the latter country V. pompona subsp.grandiflora has been recorded in the provinces of Loreto and San Martín at 1000-1100 m of elevation (Schweinfurth, 1958, as V. pompona).
It may be that this is the plant to which Ruiz refers in his Relación under the name of "Vanilla officinalis Vulgo Vaynilla", explaining that the Indians of Cuchero collect the fruits to be sold in Huánuco (2007: 164; Ms. 20).The journal makes mention of another species of the genus Vanilla, collected du-Type: Peru.Pavón s.n.(holotype, G).Trichoceros muscifera Kraenzl., Bot. Jahrb. Syst. 37: 387. 1906 Heinrich Gustav Reichenbach described his T. armillatus from the collections of Ruiz and Pavón, acquired for Jules Paul Benjamin Delessert by Obadiah Rich at the auction of Lambert's specimens, which were originally sold by J. Pavón from the materials kept in the "Oficina Botánica".For this reason I suggest that the specimen in MA (81086!), as well as the illustration of the same plant (AJB, Div.IV, 1344, Pulgar's plate number 113) are probably referable to the type collection.
The species is known from Colombia to Peru and Bolivia, where it grows on exposed steep slopes covered with mosses, usually at high elevations up to 4000 m.In Peru, populations of T. antennifer have been recorded in the montane wet forests of Cajamarca, Cuzco, Junín, Huánuco, and Puno provinces, where they are commonly found as terrestrial on dry, mossy cliffs and rocks, and more rarely as epiphytes in low highland woods, at 1800 to 3000 m.As well as other species of the genus, the flowers of T. antennifer are pollinated by pseudo-copulation, simulating female flies of the genus Paragymnomma.
The creeping habit, with distant, ovoid pseudobulb mostly covered by distichous, coriaceous, gray green, foliaceous sheaths, and a single, rudimentary leaf at apex, the flowers with a lip deeply 3-lobed at the base, the lateral lobes linear, ciliate, the pubescent midlobe much larger, with a fleshy thickening below in the middle, and the column provided with a cluster of long bristles at the rear distinguish T. antennifer.The species has been recorded in Costa Rica, Ecuador, Peru, Bolivia, and northern Brazil.In Peru, populations of X. squalens are broadly distributed in Ayacucho, Cajamarca, Huánuco, Junin, Loreto, Puno and San Martin, in wet tropical to montane forests at 400-1800 meters.According to the manuscript description kept at the RJB (AJB, Div.IV, 4, 3), the specimen illustrated by J.G. Rivera was collected in the forests of Chicoplaya, probably between 1796 and 1799.

Vanilla hamata
Xylobium squalens may be recognized by the ovoid pseudobulbs, the basally inflated bracts of the inflorescence, the linear floral bracts, and the thick midlobe of the lip with conspicuous verrucous veins, disposed in lines.Schweinfurth (1970) and Bennett & Christenson (1995) treat this name as a F. Pupulin ring the expedition in Pozuzo in 1784, and recorded as "Vanilla volubilis V. Vaynilla" (Ruiz, 2007: 256;Ms. 44), of which some fruits are conserved in the carpologic collection of the RJB (see supra, under the notes to V. hamata).later synonym of X. variegatum (Ruiz & Pav.) Garay & Dunsterv.For a complete list of possible synonyms of X. squalens, see Brako and Zarucchi, 1993.86.Xylobium undulatum (Ruiz & Pav.) Rolfe, Orch. Rev. 20: 43. 1912 Schweinfurth (1960) considered X. undulatum an obscure species, and suggested it is a synonym of X. squalens (Lindl.)Lindl.Ruiz (2007: 287;Ms. 54) prepared a description of Maxillaria undulata during his stay in Muña, between August and September, 1786 and, according to the diary, the species was probably illustrated at the same time.Both the drawings by Gálvez show a plant of the same species, and both are annotated «Maxillaria undulata» in Ruiz' handwriting.Ruiz's manuscript description of Maxillaria undulata («Gynadria Diandria / Maxillaria undulata», AJB, Div.IV, 4, 3, fol.9) refers to the illustration number «144», but this is the number assigned to both the paintings by Gálvez, so I cannot indicate which one was actually taken from the type specimen.(Ruiz & Pav.) Garay & Dunst., Venez. Orchid. Ill. 2: 342. 1961.Found in most South American countries from Venezuela and Colombia to Brazil, Bolivia and Peru, X. variegatum inhabits wet premontane to montane forests at 500 to 3000 m.In Peru, it is fairly common in montane wet forests at around 1500 m, with populations infrequently found up to 3000 m.

Xylobium variegatum
The subcylindric to pyriform pseudobulb with 2-3 apical, distinctly petiolate leaves, the lateral, densely many-flowered inflorescence provided with scarious, acuminate, loose bracts, and the membranaceous flowers, white internally and reddish brown externally, and the strongly verrucose lip are diagnostic.Humboldt and Bonpland collected the type of Dendrobium maculatum in the province of Jaen de Bracamoros, along the eastern slopes of the Andes in northern Peru (Sandwith, 1926).Zygopetalum maculatum is known from Peru, Bolivia and Brazil, where it inhabits wet, semi-boggy areas.

Zygopetalum maculatum
The large and colorful flowers, pleasantly fragrant, with an obovate, pubescent lip veined with bluish-purple, distinguish the species.Zygopetalum maculatum is probably best known under the names of Z. mackaii Paxton, 1836), an illegitimate homonym of Z. mackaii Hook.(1827), the latter apparently endemic to Brazil, and Z. intermedium.
cate-recurved leaves, belonging to the so-called "Maxillaria aggregata" complex.The oldest name for this group is Dendrobium aggregatum, originally described from Peru; other species of this complex have been recorded there, among which are two closely allied species, O. nubigenum Rchb.f.(the type, Colombia) and O. minutiflorum (D.E.Benn.&Christenson)M.A.Blanco & Ojeda.In the absence of flowers, both in Brunete's plate and in the only extant sheet in MA (probably referrable to this illustration), a definitive identification is not possible.
Herbarium: No specimens found in MA.
Sobralia dichotoma is known from Colombia to Bolivia and Peru, where it inhabits wet premontane and montane cloud forests, from 1400 to over 3500 m.The plants grow terrestrially in open woodlands on clay or rocky slopes, usually in shaded spots.
flower, with deeply fimbriate lip, may perhaps correspond to Sudamerlycaste cobbiana (B.S. Williams) Archila, while the main vegetative parts (i.e., large leaves and long inflorescence) are probably of a species of Ida [Sudamerlycaste] sect.Cinnabarinae Oakeley.MA 810772, which has the same number («25/28») on the label of the Herbarium Peruvianum of Ruiz and Pavón, is probably part of the same, large vegetative specimen.Oakely (correction label 2009) identified it as Ida heynderycxii or I. gigantea.Sudamerlycaste ciliata is known from Colombia, Ecuador, Peru, and Bolivia, where it inhabits wet submontane and montane forests at 1500 to over 2500 m as a terrestrial or epiphytic plant, frequently growing on steep roadside cliffs.