Romanoa  

Climber, monoecious. Exudate absent*. Unarmed*. Indumentum present, hairs simple. Stipules free*, simple, unlobed, entire *, not spine-like*, not leaf-like*, without glands. Leaves distributed evenly along stem, alternate, simple, unlobed, margin toothed or almost entire, base symmetrical, blade not pellucid-punctate, leaf glands 2 at leaf base and in 2 rows on leaf underside; with 3–5 veins from base; domatia absent*; stipel-like appendages absent*. Petiole long, without swellings or bends at base or apex*. Inflorescence with axis, axillary, raceme-like, solitary, bisexual with 1–2 female flowers at the base, the rest male; bracts not leaf-like*, green; pedicels present, not articulated*. Male flowers: sepals 5, valvate, partially fused, greenish; petals 0; disc (or disc-like structure) outside the staminal whorl (extrastaminal), annular (entire or lobed); stamens 10, free; anther without conspicuous modification, thecae in bud extrorse or introrse; pistillode present. Female flowers: sepals 5–6, imbricate, free, greenish; petals 0; disc 0; ovary locules 3, ovules per locule 1; styles 1, partially to completely fused (stigmas may be free), 3-branched at apex, styles or stigmas not flat*, surface smooth; staminodes absent. Fruit dehiscent (irregularly) or indehiscent, slightly 3-lobed, not sculptured, greenish to brown; seed without appendage, covering or membraneous layer*, not fleshy; embryo flat, not minute, cotyledons leaf-like.

An asterisk * indicates a state has been assumed but not yet confirmed.

World Checklist: 1 species: Romanoa tamnoides.

See also Gillespie, L.J. (1993) A synopsis of neotropical Plukenetia (Euphorbiaceae) including two new species. Systematic Botany 18(4): 575 -592.