Pleioceras Baill.

Apocynaceae, A. J. M. Leeuwenberg & F. K. Kupicha et al. Flora Zambesiaca 7:2. 1985

Morphology General Habit

Shrubs, lianas or trees up to 9 m. high, with white latex.

Morphology Stem

Branches unarmed, with pale lenticels; branchlets terete, often sulcate when dry.

Morphology Leaves

Leaves opposite, those of a pair equal or subequal, shortly petiolate, with colleters in one or two rows in the axils; lamina acuminate, rounded or cuneate at the base.

Morphology Reproductive morphology Inflorescences

Inflorescences terminal, paniculate, several- to many-flowered, lax. Lower bracts leafy; others narrowly oblong, acute, with colleters in the axils.

Morphology Reproductive morphology Flowers

Flowers actinomorphic except for the sometimes slightly unequal sepals, small.

Morphology Reproductive morphology Flowers Calyx

Calyx persistent beneath the fruit; sepals green, connate at the base, ovate, imbricate, entire, pubescent or glabrous outside, ciliate, inside at the base near the edge with 0–1 triangular or ovate colleters (in whole flower 3–10).

Morphology Reproductive morphology Flowers Corolla

Corolla subhypocrateriform; tube yellow and violet or dark-red, ventricose in the middle, outside glabrous at the base and minutely pubescent at the apex, inside at the apex just below the appendages with a narrow pilose zone; lobes yellow with a brownish-violet tinge, in the bud overlapping to the left, elliptic, rounded, entire, ciliate, minutely pubescent outside, with an alternating set of appendages inside. Appendages bright yellow, in a set of 1–3, shortly truncate or filiform, glabrous or pubescent, plus 2–4 long filiform glabrous ones.

Morphology Reproductive morphology Flowers Androecium Stamens

Stamens exserted, but covered by the appendages; filaments short, filiform, glabrous outside, inside hispid towards the apex and with a triangular swelling on the base of the connective; anthers introrse, sagittate at the base, apiculate and pilose at the apex, otherwise glabrous, fertile for y of the length just below the apices.

Morphology Reproductive morphology Flowers Gynoecium Pistil

Pistil glabrous or sometimes with a few papillae; ovary superior, subglobose; carpels two, free, rounded; disk none; style split at the base; clavuncula with a thin ring at the base, almost cylindrical, covered by the anthers and inside with the triangular swellings of the connectives adnate to the clavuncula; stigma minute, bilobed.

Morphology Reproductive morphology Flowers Gynoecium Ovary Ovules

Ovules numerous, in several rows.

Morphology Reproductive morphology Fruits

Follicles 2, spreading, almost free, pendulous, slender, adaxially dehiscent, glabrous; wall thinly coriaceous, striate, grooved when dry, glabrous outside.

Morphology Reproductive morphology Seeds

Seeds numerous, in two or more rows, linear to very narrowly oblong, finely grooved, glabrous, with a ± dense tuft of retrorse hairs at the apices, embryo large, surrounded by the very scanty whitish endosperm.