Triandra Mart.-Azorín, M.B.Crespo, M.Á.Alonso, N.R.Crouch & M.Pinter
- Dataset
- A generic monograph of the Hyacinthaceae subfamily Urgineoideae
- Rank
- GENUS
- Published in
- 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): 1-143, DOI: 10.11646/phytotaxa.610.1.1, URL: http://dx.doi.org/10.11646/phytotaxa.610.1.1
Classification
- kingdom
- Plantae
- phylum
- Tracheophyta
- class
- Magnoliopsida
- order
- Caryophyllales
- family
- Amaranthaceae
- genus
- Triandra
description
Description: — Small bulbous geophyte. Bulb hypogeal, ovoid to subglobose, 8 ‒ 18 mm in diam., with white, fleshy, compact, inner scales and pale brown, membranous outer tunics. Roots thickened and branched. Leaves 2 ‒ 6 per bulb, hysteranthous, 2 ‒ 8 cm long, filiform, to 1 mm in diam., subterete or very slightly flattened, green, smooth, glabrous. Inflorescence a lax, erect raceme, 2 ‒ 5 cm long, with 4 – 8 flowers; peduncle 4 ‒ 8 cm long, brownish, erect, terete, smooth; pedicels 7 ‒ 9 mm long, smooth, patent proximally and soon arching downwards distally at anthesis, curving upwards in fruit. Bracts ovate-lanceolate, small, ca. 0.5 mm long, lowermost with short spur, ca. 0.3 mm long, persistent; bracteoles absent. Flowers stellate, nodding, with strongly reflexed tepals at full anthesis with tips touching flower pedicel, nocturnal, opening in late evening and closing before sunrise, fragrant during night. Tepals 6, biseriate, 5 ‒ 6 mm long, narrowly oblong, slightly constricted along middle, obtuse, whitish to pale brown, with darker brownish longitudinal band more evident on abaxial side, almost free to very shortly connate for 0.5 mm. Stamens 3, only inner whorl present, outer absent with no basal rudiments, erect, straight, approaching ovary and style, with 3 anthers placed near stigma; filaments 3.5 ‒ 3.8 mm long, filiform, white, subterete, only slightly widened at base, connivent to style, free, not adnate to tepals; anthers oblong, ca. 0.6 mm long after dehiscence, subbasifixed, yellow to orange, with yellow polen. Ovary ovate, 1.9 ‒ 2.2 mm long, pale brown to yellowish. Style 2.0 ‒ 2.2 mm long, erect, white, filiform and narrow, ending in undifferentiated stigma. Capsule ovate, trigonous, 4 ‒ 5 mm long, pale brown, valves completely dehiscing from base, tepals cohering and inrolled above ovary after anthesis, circumcissile from base and persisting as a cap at the top of the developing capsules. Seeds ellipsoidal to broadly ellipsoid, flattened, 6 ‒ 16 mm long, testa black, glossy, with subpolygonal cells. Number of species and distribution: — A monotypic genus originally described from a single locality on the Pella-se-Berge, northwestern South Africa, near to the border with Namibia, a locality included in the Karoo-Namib Region (sensu Takhtajan 1986) (Fig. 49). Recently, Manning (2022) cited the collection Harrower 6188 (NBG) as the second known locality for this species occurring in the Pienaarsfontein-se-Berge, Koedoesberge near Touwsrivier, representing an extension of more than 400 km to the south, near the Tanqua Karoo in the Western Cape Province of South Africa. Two additional populations were found, in September 2015 in the Naib se Berg and in August 2022 in the Nouroepberge near Dabenoris Mountains, both in vegetative stage, by M. Martínez-Azorín & collaborators (MMA 1269 ABH 74121! and MMA 2078 ABH 74374! respectively). The phylogenetic analyses of these samples and their recent flowering in cultivation confirmed their placement in Triandra. Karyology: — Not studied yet.
type_taxon
Typus generis: — T. pellabergensis Mart. - Azorín, M. B. Crespo, M. Á. Alonso, N. R. Crouch & M. Pinter (holotype).