Chamaecrista comosa, E. Mey., Comm. Pl. Afr. Austr.

Musandiwa, Liada, Magee, Anthony R. & Boatwright, James S., 2022, A Taxonomic Revision of Chamaecrista (Caesalpinioideae, Cassieae, Cassiinae) in Southern Africa, Systematic Botany (Basel, Switzerland) 47 (4), pp. 992-1011 : 1000-1001

4. CHAMAECRISTA COMOSA E.Mey. , Comm. Pl. Afr. Austr. 1: 160 (1836);

Brummitt in Fl. Zambesiaca 3(2): 142 (2007). Cassia comosa (E.Mey.) Vogel , Syn. Gen. Cassiae 65. (1837); Ghesquiere in Bull. Jard. Bot. 9: 153 (1932); Steyaert in Bull. Jard. Bot. Brux. 20: 251 (1950); Brenan in F.T.E.A Legum.- Caesalp.: 89 (1967); Gordon-Gray in F.S.A. 16(2): 96 (1977).

TYPE: SOUTH AFRICA. KwaZulu-Natal Province, Port Edward, 500 m from the sea opposite Hills , Grobbelaar 1534 (neotype: PRE!, designated here).

Note: The original Drege collection (South Africa, Eastern Cape, between Umzimvubu River [Omsamwubo] and Umsikaba River [Omsamcaba], Drege (?B)) cited by Meyer could not be located as most of his collections housed at B are presumably largely destroyed, so we here designate a collection of Grobbelaar as neotype as it is the most complete with mature flowers and fruits.

Perennial herbs, to 0.6 m high. Stems erect, simple or sub-simple, glabrous to pubescent or densely covered with whitish to yellowish spreading hairs, arising from a woody rootstock. Leaves paripinnate, 20–150 × 10–25 mm, oblong to linear oblong, slightly tapering distally; stipules 5–15 × 1–4 mm, narrowly triangular, base oblique, apex acuminate, margin ciliate; extrafloral nectaries at or below the top of petiole, 1.2–6.0 × 0.4–4.0 mm, sessile, elliptic, depressed in the middle, often with dark centre; rachis channelled, channel margin ciliate. Leaflets (5)11–36-jugate, 4–17 × 2–5 mm, oblong, base oblique, apex rounded to obtuse, margin hairy. Inflorescence supra-axillary, 2–6 flowered; flowers 6–17 × 7–20 mm; bracts 3–4(5) mm long, base oblique, apex acuminate; bracteoles 2, glabrous, towards top of pedicels. Pedicels glabrous or with spreading hairs, at flowering 10–26 mm long, at fruiting 15–27 mm long. Sepals 5, ovate, 6–12 × 3–5 mm, with spreading hairs on the outer surface. Petals 5, obovate, 7–15 × 4–8 mm, bright yellow. Stamens 9, straight or slightly curved, anthers in two series, (5)6 medium ± 5 mm long, 3(4) others often the largest, up to 9 mm long, filaments very short ± 1 mm long. Ovary ± 10 mm long, densely covered with white hairs, style glabrous, slightly curved. Pods 33–65 × 3–7 mm, spreading pubescent, straight, flattened. Seeds 3–5 × 1–3 mm, rhomboid, flattened, light brown to blackish, margin often with a thin line.

Diagnostic Characters — Chamaecrista comosa is one of the most easily recognisable species of Chamaecrista in southern Africa. It shares large flowers with C. capensis but is readily distinguished by the long leaves, up to 150 mm (to 50 mm long in C. capensis ), with leaflets 2–5 mm wide (1–3 mm wide in C. capensis ) and large, sessile extrafloral nectaries, 1.2–6.0 × 0.4–4.0 mm, depressed in the middle or sunken in on the rachis (circular, concave, sub-sessile or attached with short stalk in C. capensis ).

Note — Meyer (1836) described Chamaecrista comosa for its large, sessile extrafloral nectaries, large leaves bearing broad leaflets, and large flowers. In his treatment of the African and Asian species of Chamaecrista Steyaert (1950) recognised two varieties (viz. Chamaecrista comosa var. capriconia and Chamaecrista comosa var. lanata ). Chamaecrista comosa var. lanata was established based on its lanate indumentum and C. comosa var. capriconia for its smaller morphology. Gordon-Gray and Schorn (1975) later included Chamaecrista comosa var. lanata within C. comosa var. comosa , a decision that is supported by the present study. Following examination of available herbarium material, two varieties were recognised; one that occurs in coastal areas and one that occurs in drier areas. Based on field studies and examination of herbarium material C. comosa var. capriconia and C. comosa var. comosa need to be raised to subspecific level on the basis of different habitat preferences ( C. comosa var. comosa is restricted to open grassland with high water table on granite derived soil or sand, and C. comosa var. capriconia in grassland in dried areas usually on sandy soil ( Gordon-Gray and Schorn 1975)), distribution patterns (i.e. C. comosa var. comosa is restricted to the coastal areas of KwaZulu-Natal and Eastern Cape, while C. comosa var. capriconia has a more northern distribution extending beyond the region to Zimbabwe), and morphological differences ( C. comosa var. capriconia is smaller in its general morphology).

Two subspecies are recognised: