Opilia Roxb.

Scientific Description

Family Opiliaceae.

Habit and leaf form. Trees (small), or shrubs, or lianas. Partially parasitic. On roots of the host. Leaves cauline. Stem internodes solid. Self supporting, or climbing. Mesophytic. Leaves alternate; distichous; petiolate; non-sheathing; simple. Leaf blades entire; elliptic to ovate, or oblong to ovate; pinnately veined (usually prominent though fine, midrib prominent beneath, lateral veins conspicuous); cross-venulate; attenuate at the base (often), or rounded at the base (sometimes). Leaves without stipules. Leaf blade margins entire. Leaf anatomy. Extra-floral nectaries absent. Stem anatomy. Secondary thickening developing from a conventional cambial ring.

Reproductive type, pollination. Fertile flowers hermaphrodite. Unisexual flowers absent. Plants hermaphrodite.

Inflorescence and flower features. Flowers aggregated in ‘inflorescences’; in racemes (or raceme-like). Inflorescences axillary. Flowers pedicellate (pedicels and rachis tomentose with brown or yellow hairs); bracteate (each subtends 3 flowers, scale-like or peltate or broadly ovate, ciliate, closely imbricate, caducous before anthesis). Bracts deciduous. Flowers ebracteolate; small; fragrant; regular; 4 merous, or 5 merous; cyclic; tetracyclic. Free hypanthium absent. Hypogynous disk present; of separate members (alternating with the stamens). Perianth with distinct calyx and corolla; (4–)5; 2 -whorled; isomerous. Calyx present (B); (4–)5; 1 -whorled; polysepalous, or gamosepalous; lobulate, or blunt-lobed; open in bud; cupuliform; regular; persistent; non-accrescent. Calyx lobes oblong. Corolla present (B); (4–)5; 1 -whorled; polypetalous, or gamopetalous; valvate; regular; green (yellowish). Androecial members definite in number. Androecium 4–5. Androecial members free of the perianth, or adnate; all equal; free of one another; 1 -whorled. Androecium exclusively of fertile stamens. Stamens (4–)5; all more or less similar in shape; isomerous with the perianth; alternisepalous. Anthers dehiscing via longitudinal slits; tetrasporangiate. Gynoecium 2–5 carpelled. The pistil 1 celled. Carpels reduced in number relative to the perianth to isomerous with the perianth. Gynoecium syncarpous; eu-syncarpous; superior. Ovary unilocular; 1 locular; sessile. Gynoecium non-stylate (AK), or stylate (B). Styles 1; attenuate from the ovary; apical; shorter than the ovary at anthesis. Stigmas 1. Placentation basal, or free central. Ovules in the single cavity 1; pendulous, or ascending; non-arillate; anatropous.

Fruit and seed features. Fruit puberulous, orange-yellow, edible; endocarp thin and crustaceous, yellow; indehiscent; a drupe; 1 locular; 1 seeded. Seeds endospermic. Endosperm oily. Seeds without a testa. Embryo well differentiated. Cotyledons (2–)3, or 4. Testa lacking.

Etymology. Derivation unknown; no indication by author.