Spirophyllos Mart.-Azorín, M.B.Crespo & M.Á.Alonso, 2023

Martínez-Azorín, Mario, Crespo, Manuel B., Alonso-Vargas, María Ángeles, Pinter, Michael, Crouch, Neil R., Dold, Anthony P., Mucina, Ladislav, Pfosser, Martin & Wetschnig, Wolfgang, 2023, A generic monograph of the Hyacinthaceae subfamily Urgineoideae, Phytotaxa 610 (1), pp. 1-143 : 87-90

20. Spirophyllos Mart.-Azorín, M.B.Crespo & M.Á.Alonso gen. nov.

( Figs 50–51 ).

Typus generis:— S. noctiflorus (Batt. & Trab.) Mart. -Azorín, M.B.Crespo & M.Á.Alonso ≡ Urginea noctiflora Batt. & Trab. (holotype).

Diagnosis:— Genus distinctissimus singulari characterum combinatione a ceteris generibus Urgineoideae diversus et facile distinguendus, nempe foliis anguste linearibus, spiraliter contortis; floribus nocturnis nutantibus, staminum filamentis rectis a basi ovario styloque conniventibus sed supra medium implexis divergentibusque; et capsulis magnis, ovatis vel subglobosis, patentibus.

Description:—Bulbous geophyte. Bulb hypogeal, ovoid, to 5 cm in diam., with white inner scales and greyish, membranous outer tunics. Roots thickened and branched. Leaves 5‒15 per bulb, hysteranthous, 10‒20 cm long, narrowly linear, hemiterete to slightly flattened, distinctly coiled at least along upper half, green, somewhat glaucous, smooth, glabrous. Inflorescence a lax, erect raceme, 10‒20 cm long, with 4–25 flowers; peduncle 10‒20 cm long, erect, terete, smooth, dull grey-green to reddish-brown; pedicels 6‒20 mm long, arching downwards at anthesis, subpatent and sigmoid in fruit. Bracts ovate-lanceolate, 1‒2 mm long, lowermost with distinct spur as long as or longer than blade, caducous; bracteoles absent. Flowers stellate with strongly reflexed tepals at full anthesis, nodding, nocturnal, opening in late evening and closing before sunrise, fragrant during night. Tepals 6, biseriate, 7‒10 mm long, narrowly lanceolate, pale brown to carneous colour, with darker brownish-greenish longitudinal band more evident on abaxial side, almost free. Stamens 6, erect, straight or very slightly curved, connivent to style and crossing each along upper third; filaments linear, only slightly widened at base, narrowly conical and tapering, 6‒7 mm long, white or cream colour, adnate to tepals at base; anthers oblong, 1‒2 mm long, medifixed to subbasifixed, deep orange after dehiscence, connective with a pit at filaments insertion, with yellow pollen. Ovary ovate, 4‒5 mm long, 6-lobed basally, pale yellow. Style 5‒6 mm long, suberect, white, filiform, ending in minute stigma. Capsule ovate to subglobose, trigonous, obtuse, 7‒10 mm long, pale brown. Seeds ellipsoidal, flattened, 6‒8 mm long, with black, glossy testa.

Number of species and distribution:—This new genus currently includes one species restricted to desert regions of northwestern Africa (southern Morocco and Algeria), south of the Atlas Mountain range ( Fig. 49 ). Therefore, it is restricted to the Saharo-Arabian Region (sensu Takhtajan 1986).

Karyology:—2n=20 ( Azizi et al. 2016).

History, diagnostic characters, and taxonomic relationships:— Urginea noctiflora Battandier & Trabut (1894: 505) was described from the border of the Sahara Desert in Algeria showing a number of clear morphological differences with regard to all known European species of Urgineoideae , such as the narrowly linear, distinctly coiled leaves, nocturnal nodding flowers with the filaments straight, connivent to the style and crossing along the middle, and the patent, large, ovate capsules ( Battandier & Trabut 1894).

The phylogenetic study by Martínez-Azorín et al. (2021) included six samples of different populations of Urginea noctiflora from Morocco provided by A. Garcin constituting a strongly supported clade, which is sister to another strongly supported clade merging four samples of Urginea fugax ( Moris 1827: 46) Steinheil (1834: 328) and U. ollivieri Maire (1938: 453) from Sardinia, Ibiza, and Morocco (corresponding to Urginea s.str. in the sense of the present work). This same relationship was already shown by Pfosser et al. (2006). However, Urginea noctiflora differs from typical Urginea species in the distinctly coiled leaves, a character not known in any other Urgineoideae , and the reproductive characters listed above. We here propose the new genus Spirophyllos to include Urginea noctiflora based on the distinct morphological differences described above and its genetic divergence.

Accepted species and required new combination:—

Spirophyllos noctiflorus (Batt. & Trab.) Mart. -Azorín, M.B.Crespo & M.Á.Alonso comb. nov. ≡ Urginea noctiflora Batt. & Trab. in Compt.- Rend. Assoc. Franc. Besancon 1893(2): 505 (1894), basionym ≡ Urginea noctiflora Batt. & Trab. subsp. helicophylla (Maire) Maire in Fl. Afric. N. 5: 162 (1958), nom. illeg. ≡ Urginea noctiflora Batt. & Trab. var. helicophylla Maire in Jahand. & Maire, Cat. Pl. Maroc 3: 870 (1934), nom. illeg. ≡ Duthiea noctiflora (Batt. & Trab.) Speta in Stapfia 75: 170 (2001) ( Figs 50–51 ). Type:— ALGERIA. Ouargla, Gara près de Sedrata et partout route a Mzab, 20 May 1902, L. Chevallier s.n. (P01848250! neo. designated here).

Figures

FIGURE 49. Approximate distribution ranges of accepted genera in Urgineoideae.

FIGURE 50. Spirophyllos noctiflorus (Batt. & Trab.) Mart.-Azorín et al. Illustration kept at MPU (MPU225773) as Urginea noctiflora Batt. & Trab. Reproduced with permission: copyright © Université de Montpellier – Herbier MPU (SPH).

FIGURE 51. Spirophyllos noctiflorus (Batt.&Trab.)Mart.-Azorínet al.incultivation fromImaoun,Morocco.a.Developing inflorescence; b. Inflorescence; c. Flower in lateral view; d. Flower in frontal view; e. Flower in dorsal view; f. Flower in lateral view with two removed tepals showing stamens disposition; g. Dissected flower; h. Indehisced anthers; j. Inflorescence section showing bracts and pedicels; k. Bulbs with coiled leaves from wild plants near Imaoun (Photographs by A. Garcin). Scales: a, b: 1 cm, c–g, j: 5 mm, h: 2 mm.