INTRODUCTION
The taxonomy of Ornithogalum L. s. str. (i.e., according to Martínez-Azorín & al., 2011) in the Iberian Peninsula within the last two centuries can be considered diverse and confusing. The concept of taxa in this group were used in different ways in the Iberian and western European floras (Zahariadi, 1980; Pignatti, 1982; Aeschimann & al., 2004; Martínez Azorín & al., 2010; Lambinon & Verloove, 2012; Lauber & al., 2012; Stace, 2014; Tison & Foucault, 2014; Tison & al., 2014). Moreover, identification of plants in this group is usually complicated, especially when the subterranean parts or fruits are not available. This led for a complex taxonomy in the group in which up to 11 species, among them O. umbellatum L., were cited in the Iberian Peninsula, most of them being initially described from other territories (Martínez Azorín & al., 2010).
In the frame of the works towards the taxonomic revision of Ornithogalum for Flora iberica, Martínez Azorín & al. (2013) reduced the number of Iberian species of Ornithogalum s. str. (O. subgen. Ornithogalum) to three: O. bourgaeanum Jord. & Fourr., O. divergens Boureau, and O. baeticum Boiss., the presence of O. umbellatum being not confirmed.
The extreme cytotype variation found in the aggregate of O. umbellatum, in which many ploidy levels (2n = 27, 36, 45, 54, 72, 90, 108; cf. Neves, 1952; Tornadore & Garbari, 1979; Garbari & al., 2003) occur together with diploids and aneuploids, is perhaps in the origin of the wide taxonomic and nomenclatural confusion. These ploidy levels have been connected to two or three morphotypes (Gadella, 1972; Gadella & Raamsdonk, 1981; Moret 1991, 1992; Moret & Favereau, 1991; Moret & Galland, 1991, 1992; Raamsdonk 1999; Speta, 2000; Garbari & al., 2003, 2008; Aquaro & Peruzzi, 2006), in which at least two biological entities are well differentiated. Ornithogalum divergens is usually applied to hexaploid plants (2n = 54) with wide pseudocorymbose inflorescences, bearing very long and patent or slightly reflexed lower pedicels, with short bracts not reaching half of the length of the subtending pedicel in fruit, and with bulbs producing many small, spherical, long pedicellate bulbils, usually not leaved and attached to the basal plate. Plants of the triploid cytotype (2n = 27), to which the name O. umbellatum is commonly applied, produce corymbose inflorescences with the lowermost pedicels erect-patent in flower, rarely reflexed in fruit, and bulbs bearing sessile, medium size bulbils, commonly generating leaves in their first year.
Recently three populations of O. umbellatum s. str. were found in northeastern Spain and southern France by G. Mercadal in the frame of his PhD thesis, in the meadows of the Mediterranean areas of Catalonia. They are the first full-checked records of this species in the Iberian flora.
The name O. umbellatum has been widely misapplied to populations from northeastern Iberian Peninsula and southeastern France, which indeed correspond to O. divergens and even O. bourgaeanum. In the Flora dels Països Catalans (Bolòs & Vigo, 2001), a single species, O. umbellatum, is accepted for Ornithogalum s. str. (i.e., according to Martínez Azorín & al., 2011), in which three subspecies are included. The first subspecies, O. umbellatum subsp. umbellatum, that includes O. divergens as synonym, was used to name plants of O. divergens sensu Martínez Azorín & al. (2009, 2010, 2013). The second and third subspecies, O. umbellatum subsp. monticolum (Jord. & Fourr.) O. Bolòs & Vigo and O. umbellatum subsp. baeticum (Boiss.) O. Bolòs & Vigo are used to name plants belonging to O. bourgaeanum sensu Martínez Azorín & al. (2010, 2013). In the Flora Manual del Països Catalans (Bolòs & al., 2005), two species are accepted for Ornithogalum s. str., O. umbellatum to name O. divergens sensu Martínez Azorín & al. (2009, 2010, 2013), and both O. orthophyllum subsp. monticola (Jord. & Fourr.) O. Bolòs & al. and O. orthophyllum subsp. baeticum (Boiss.) Zahar. to name plants of O. bourgaeanum sensu Martínez Azorín & al. (2010, 2013). Therefore, it seems that recent Catalan floras did not recognise the differences between O. umbellatum and O. divergens, as triploid and hexaploid cytotypes of the polyploid complex of O. umbellatum, as explained above, and merged both cytotypes in a single taxon, O. umbellatum. It is worth mentioning that according to our data O. orthophyllum and O. baeticum do not occur in Catalonia (Martínez Azorín & al., 2010). Other works in Europe (v. gr., Prevost, 2002; Lambinon & Verloove, 2012; Jauzein & Nawrot, 2013; Stace, 2014) accept O. divergens as a subspecies of O. umbellatum.
A complete morphological description is presented for O. umbellatum to complete the information of the genus of Flora iberica. An identification key is also presented for the Iberian species of Ornithogalum s. str., O. baeticum, O. bourgaeanum, O. divergens, and O. umbellatum, which complements that presented by Martínez-Azorín & al. (2013).
TAXONOMIC TREATMENT
Ornithogalum umbellatum L., Sp. Pl.: 307 (1753)
Geophyte, deciduous. Bulb 16-20(30) × 15-18(25) mm, pyriform in early stages and ovoid to slightly depressed at maturity; outer tunic whitish, surrounded by numerous solid bulbils. Bulbils of different sizes; the largest 6-8(10) × 4-6(8) mm, usually bearing leaves their first year of life, pyriform to ovoid, being larger than ca. 35% of mother bulb size; the smallest 3-4(5) × 2-3 mm, lacking leaves, ovoid to spherical, lacking pedicles or very shortly pediculate. Floral stem (8)10-18(20) cm long, green, smooth, glabrous. Leaves 13-15 × 0.25-0.4(0.5) cm, (2)4-8(10) per floral stem, green, strap-like, canaliculate, glabrous, with a whitish or translucent central longitudinal band 0.2-1.2 mm wide on the adaxial side, usually longer than the inflorescence, withering at the upper portions. Inflorescence a corymbose raceme, 3-8 × 3-8 cm, with few flowers, usually with 4-7, up to 14; lowermost pedicels in flower 3-6(11) cm long, spreading; lowermost pedicels in fruit erect-patent, rarely slightly reflexed with incurved apex. Bracts 2.5-3 cm long, usually longer than the half length of the lowermost pedicels in fruit. Flowers 26-42 mm in diameter, stellate, slightly fragant. Tepals lanceolate, acute to obtuse, white on the adaxial side and white with a broad longitudinal green band on the abaxial side; outers 18-24 × 5-8 mm, lanceolate-obovate; inners 8-16 × 3-6 mm, lanceolate. Stamen 1/2 to 2/5 the length of the tepals; filaments lanceolate-oblong, with the widest portion in the basal part, progressively tapering to the apex, the outers 8-12 × 1.5-2 mm, the inners 9-13 × 1.8-2.5 mm; anthers oblong, pale yellow, pollen yellow. Ovary 5-9 × 4-6 mm, pale to dark green, oblong and truncate in lateral view, with 6 distinct, equidistant ribs in transversal section; style (2.5)2.8-3.5(4) mm long, usually 2/5 the length of the ovary; stigma slightly trilobate-punctiform. Capsule 8-14 × 5-8 mm, oblong-ovoid to obovoid, at matury with 6 equidistant ribs in section, more rarely in pairs. Seeds 1-15 per capsule, 1.5-1.7 × 1.3-1.5 mm, black, globose, slightly apiculate. 2n = 27 (triploid).
Geographic distribution, habitat, phenology, and curiosities
Ornithogalum umbellatum inhabits crops, grasslands, gardens, meadows, and disturbed grounds; altitude: from 0 to 100 m. It blooms from April to May.
In the Iberian Peninsula we have only found O. umbellatum in l’Alt Empordà and el Gironès (Girona province), although probably is also present in other regions of Catalonia or even other areas of northern Spain. In southeastern France, we know the species from Tuïr, in the region of Perpinyà, from where it spreads northwards to the Loire valley, its locus classicus, and other central European countries. We suggest to revisite the localities where O. umbellatum has been cited in the Iberian Peninsula to check the diagnostic characters of this species.
The bulb of O. umbellatum is toxic for animals (Villar & al., 2001; Mateos & Álvarez, 2010), but once boiled it loses its toxicity (Texidor, 1871).
Identification key of Ornithogalum s. str. in the Iberian Peninsula
| 1. |
Style (3.8)4-6(6.5) mm long; leaves glaucous at early stages |
O. baeticum
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| – |
Style (2)2.5-3.8(4) mm long; leaves green at early stages |
2 |
| 2. |
Bulb lacking secondary bulbils (rarely 1-3), although the mother bulb can be split in portions of similar size that share the basal plate and are covered by the outer tunic; mature capsule with 6 ribs grouped in pairs in transversal section (observe different capsules); fruiting pedicels usually ascending, sometimes patent to slightly reflexed; plant mostly occurring in the montane stage (from basal to subalpine stages) |
O. bourgaeanum |
| – |
Bulb surrounded by numerous secondary bulbils (either on the outside of the outer tunic or covered by it); mature capsule with 6 ribs equidistant in transversal section; fruiting pedicels erect-patent to patent-reflexed; plant mostly occurring in the basal stage (reaching the montane stage) |
3 |
| 3. |
Bulb surrounded by numerous bulbils that bear leaves in their first year; bulbils of different sizes, the largest pyriform to ovoid, sessile, bearing leaves, the smaller lacking leaves, ovoid, sessile or rarely shortly pediculate; relation between the size of the largest bulbils and the mother bulb > 35%; fruiting pedicels usually erect-patent (rarely reflexed); bracts usually longer than half of the length of the pedicels in fruit; lower pedicles in fruit ≤ 11 cm long (usually ca. 5 cm long); few flowers per stem, 4-7(14) |
O. umbellatum |
| – |
Bulb surrounded by numerous bulbils lacking leaves (rarely some could bear shortly developed leaves); bulbils of similar sizes, ovoid, usually distinctly pediculate; relation between the size of the largest bulbils and the mother bulb < 35%; fruiting pedicels usually patent to reflexed; bracts usually shorter than half of the length of the pedicels in fruit; lower pedicels in fruit ≥ 5 cm long, reaching 15 cm long; many flowers per stem, 6-18(20) |
O. divergens |