Ebertia, Speta

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 : 41-42

6. Ebertia Speta

in Phyton (Horn, Austria) 38(1): 65 (1998). Typus generis:— Ebertia nana (Oyewole) Speta = Urginea nana Oyewole (holotype).

Description:—Small bulbous geophyte to ca. 8 cm tall. Bulb hypogeal, ovoid-oblong to subglobose, 2‒3 cm long, with short bulb neck, outer scales membranous and inner bulb scales white. Roots thickened and branched. Leaves 4‒10, hysteranthous, 8‒20 cm long and 1‒3 mm wide, thin, filiform and spreading or linear-lanceolate and erect to arching, green, smooth, glabrous. Inflorescence a short, dense raceme with (1–)3‒6 flowers; peduncle erect, terete, smooth, 1.5‒ 4.5 cm long, greenish to dark purple; pedicels spreading, 1‒4 mm long, glabrous; pedicels of fruits laterally recurved, to 15 mm long. Bracts broadly lanceolate, persistent, lowermost to 6 mm long with distinct flat, decurrent, bifid spur of ca. 1.5 mm long; bracteoles absent. Flowers campanulate, subpatent. Tepals 6, 5‒10 mm long, free to shortly fused at base for ca. 1 mm, lanceolate to oblong, spreading, whitish, pinkish or pale greenish with yellow or hyaline margins, sometimes slightly tinged with dark purple, with distinct dark purple brown longitudinal band on abaxial side, outers sometimes reflexed. Stamens 6, spreading; filaments 3‒4 mm long, white or greenish; anthers oblong, up to 2 mm long, opening by longitudinal slits. Ovary elongate oblong to pyramidal, 3‒4 mm long, greenish, sometimes puberulous near apex, with 10‒15 ovules per locule. Style short, 1‒3 mm long, erect, white, filiform. Capsule ovate to sphaerical, 8‒12 mm long, trigonous with blunt edges in section, mucronate, pale brown. Seeds flattened, dark brown to black, 7‒8 mm long, with membranous wings, uniseriate per locule.

Number of species and distribution:— Ebertia is known to include 2 species, occurring disjunctly in Central and West Africa, in Guinea, Sierra Leone, Nigeria and Sudan ( Fig. 8 ). It is restricted to the Guineo-Congolian Region, the Sahelo-Sudanian Subregion and the Eastern Section of the Zambezian Subregion (sensu Takhtajan 1986 and Martínez-Azorín et al. 2023a). The species occurs in frequently burnt grasslands on mountain slopes at elevations of 300‒2000 m ( Oyewole 1989, Friis & Vollesen 1999). For further information on Ebertia species see Baker (1898), Oyewole (1989), and Friis & Vollesen (1999).

Karyology:—2n=20 ( Oyewole 1988, as Urginea pauciflora (Baker) Baker ).

History, diagnostic characters, and taxonomic relationships:— Urginea pauciflora Baker (1898: 539) , not to be confused with the illegitimate U. pauciflora Baker (1901: 786) or Drimia pauciflora Baker (1892: 6) , was described by Baker (1898) based on small plants from Sierra Leone (West Africa) possessing hypogeal bulbs, leaves non-coetaneous with flowers, a short peduncle, raceme with 2‒3 campanulate flowers, stamens shorter than tepals and with flattened filaments, and inserted style. Friis & Vollesen (1999) proposed the new name Drimia sudanica Friis & Vollesen for U. pauciflora and extended the range of this species from West Africa ( Sierra Leone and Guinea) to southern Sudan. These authors added important characters such as the very short raceme with 4‒6 flowers, lanceolate bracts with a flat, decurrent spur (a character not mentioned by Baker, but matching the type material at Kew herbarium), pedicels 1.5‒2.0 mm long, tepals 5‒7 mm long, shortly connate for ca. 1 mm at the base and spreading, with a dark purple-brown midrib, stamens 3‒4 mm long, filaments spreading, ovary elongate and ca 3 mm long, and very short style. Ripe capsules and seeds were not studied.

A related species was described by Oyewole (1989) as Urginea nana Oyewole (1989: 623) from Nigeria, showing small, hypogeal, compact bulbs, filiform erect to spreading leaves that are not coetaneous with flowers, peduncle erect, up to 4 cm long, raceme short and compressed with up to 6 flowers, pedicels reflexed during fruit development, tepals 6‒10 mm long, free, the outers reflexed at anthesis, ovary pyramidal, 3‒4 mm long, style short and erect, capsule ovoid-spherical with mucronate apex, seeds flattened, subellipsoid, 7‒8 mm long, dark brown to black, and uniseriate per locule. The author also illustrated a dehisced capsule showing widely open valves, similar to those found in D. khubusensis P.C.van Wyk & J.C.Manning in Manning & Goldblatt (2018: 120), here considered to belong to Iosanthus . Further, Oyewole (1989) described a considerable morphological variation and three morphotypes in Urginea nana ; further studies are needed to improve our understanding of this taxon.

Speta (1998b) published Ebertia to include the tropical African taxa U. pauciflora and U. nana , being characterised by the hypogeal compact bulbs, filiform, proteranthous leaves, short peduncle and condensed few-flowered raceme, shortly spurred bracts, straight and patent pedicels, nocturnal, campanulate flowers with tepals shortly connate at base, filaments shorter than tepals, ovary inferior [examination of the type confirms this as erroneous], with 12 ovules per locule, style slightly thickened at the apex, pedicels of ripe capsules laterally recurved, capsules ovoid to globose, and flattened black seeds.

The phylogenetic analyses of Pfosser & Speta (1999) place a sample of E. nana as sister to a sample from Senegal named `Thuranthos indicum´ sensu lato, but fitting with Vera-duthiea in the sense of the present work. Pfosser & Speta (2001, 2004) extended the study to include four samples of E. nana ( Oyewole 1989: 623) Speta (1998b: 68) from Guinea and Senegal that constituted a well supported clade sister to “ Duthiea ” species (= Vera-duthiea ) from Senegal and Botswana. The recent phylogenetic analyses by Martínez-Azorín et al. (2023a) included three samples of Ebertia from Guinea and Senegal and form a strongly supported clade that is sister to Vera-duthiea .

Based on the above-mentioned evidence, we accept Ebertia as including E. pauciflora ( Baker 1898: 539) Speta (1998b: 68) and E. nana , taxa flowering shortly after grassland fires ( Oyewole 1989, Friis & Vollesen 1999). These two species share a small size, non-coetaneous and filiform leaves, short peduncle and condensed, few-flower racemes, subcampanulate flowers with almost free, suberect to slightly spreading tepals, stamens shorter than tepals and included, an ovoid to conical ovary ca. 3 mm long which is sometimes puberulous, and short and erect style of equal length to the ovary. Further, E. nana is unique in the Urgineoideae in having reflexed pedicels that subtend the ripe capsules, since the remaining subfamily members always support ripe capsules on erect to suberect pedicels, except for the northwest African Spirophyllos . Further studies are necessary to compare this character with U. pauciflora . The widely spreading capsule valves and seed morphology in U. nana approach Iosanthus , a genus that is related to the clade comprising Urginea , Spirophyllos , and Indurgia ( Martínez-Azorín et al. 2023a) .

Accepted species:—

Ebertia nana (Oyewole) Speta in Phyton (Horn, Austria) 38(1): 68 (1998) ≡ Urginea nana Oyewole in Ann. Missouri Bot. Gard. 76(2): 623 (1989) ≡ Drimia minuta J.C.Manning & Goldblatt in Bothalia 43(1): 77 (2013), nom. nov. ≡ Drimia nana (Oyewole) J.C.Manning & Goldblatt in Edinburgh J. Bot. 60(3): 557 (2004), nom. illeg. [non Drimia nana (Snijman) J.C.Manning & Goldblatt in Bothalia 33(1): 111 (2003)]. Type:— NIGERIA. Ilorin, near the academic area, University of Ilorin, S00/2111 (IUH holo.; FHI iso.).

Ebertia pauciflora (Baker) Speta in Phyton (Horn, Austria) 38(1): 68 (1998) ≡ Urginea pauciflora Baker, Fl. Trop. Afr. [Oliver et al.] 7(3): 539 (1898), basionym ≡ Drimia sudanica Friis & Vollesen in Nordic J. Bot. 19(2): 210 (1999), nom. nov. [non Urginea pauciflora Baker in Bull. Herb. Boissier ser. 2, 1: 786 (1901), nom. illeg., nec Drimia pauciflora Baker (1892) ]. Type:— SIERRA LEONE. Near Wallia, on the River Scarcies, 11 February 1892, G.F. Scott-Elliot 4580 (K000257328! lecto. designated by Friis & Vollesen in Nordic J. Bot. 19(2): 210. 1999; BM! isolecto.).

Figures

FIGURE 8. Approximate distribution ranges of accepted genera in Urgineoideae.