Paranecepsia Radcl.

Barberá, Patricia, Lachenaud, Olivier & Riina, Ricarda, 2022, A new species of Paranecepsia (Euphorbiaceae-Acalyphoideae) from Madagascar and its relationships among the ‘ alchorneoids clade’, European Journal of Taxonomy 834, pp. 22-37 : 25-26

Genus Paranecepsia Radcl. -Sm.

Kew Bulletin 30: 684 ( Radcliffe-Smith 1975 publ. 1976), here amended.

Type species

Paranecepsia alchorneifolia Radcl. -Sm., Kew Bulletin 30: 684 ( Radcliffe-Smith 1975 publ. 1976).

Description

Dioecious shrubs to medium-sized trees up to 15 m high, very ramose with Terminalia -like branching (Aubréville’s model); bark greyish. Indumentum of simple trichomes. Buds perulate. Stipules subulate, tardily caducous. Leaves deciduous, alternate, spirally arranged, clustered near apices of twigs and interspersed with bud scales, simple, petiolate, stipellate or not; vernation involute; leaf blade oblanceolate to elliptic, shallowly serrate or crenate-serrate with glandular teeth; venation pinnate, midrib prominent above, lateral veins 10–16 pairs, tertiary veins scalariform to reticulate; domatia present as hairy tufts in the axils of the secondary veins; basilaminar glands present or absent. Inflorescences racemose (strongly reduced in P. andrafiabensis sp. nov.), axillary, solitary; the staminate ones with 1–5 flowers per bract; the pistillate ones with 1–2 flowers; bracts small, subulate. Staminate flowers with pedicel articulate; calyx closed in bud, later splitting into 3–5 valvate lobes which become reflexed; petals absent; stamens 20–40, glabrous, with filaments free, anthers 2-locular, dorsifixed, introrse, thecae pendulous and longitudinally dehiscent, connective not enlarged; receptacle subglobose; disk glands free, interstaminal, numerous, forming a raspberry-like structure; pistillode absent. Pistillate flowers long-pedicellate; pedicels articulate; sepals 5, free, slightly unequal, elliptic to obovate, entire, foliaceous and prominently veined, green, persistent and slightly accrescent in fruit; petals 5, free, alternisepalous, linear to oblanceolate, entire, glabrous, similar in colour and texture to the sepals but much smaller and with hardly prominent venation; staminodes 1–10, sometimes absent; disc annular to slightly undulate, glabrous; ovary sessile, 2 or 3 locular, with strigose indumentum; ovules 1 per locule; styles bifid, connate at base, persistent; stigmas shortly frimbriate. Fruits capsular, 2 or 3 lobed, pubescent, dehiscent in 2 or 3 bivalved mericarps (cocci); endocarp thinly woody; columella persistent. Seeds globose, smooth, ecarunculate and exarillate, testa plain brown or mottled, hilum ellipsoid to narrowly oblong.

Key to the species of Paranecepsia

1. Leaves with petioles 0.2–0.8 cm long and stipels 2.5–5 mm long; staminate inflorescences up to 9 cm long; pistillate flowers with sepals 5–9 mm long; ovary 3-locular; fruits 5–6 × 10 mm; seed coat plain brown ........................................................................ Paranecepsia alchorneifolia Radcl. -Sm.

‒ Leaves with petioles 0.6–2.6 cm long and stipels (if present) 1–2.2 mm long; staminate inflorescences up to 1.3 cm long; pistillate flowers with sepals 9–15 mm long; ovary 2-locular; fruits 7–8× 13 mm; seed coat mottled ............................ Paranecepsia andrafiabensis Barberá & O.Lachenaud sp. nov.