Trichosanthes L.

Scientific Description

Family Cucurbitaceae.

Habit and leaf form. Herbs (sometimes woody at the base), or herbaceous climbers (or trailing). Annual. Leaves cauline (ass.). Plants with neither basal nor terminal concentrations of leaves. Stem internodes solid (ass.). Climbing; tendril climbers (simple or 2–5 branched, spiral above point or branching). Tendrils simple, or branched. Mesophytic to xerophytic. Leaves alternate; spiral; petiolate; non-sheathing; simple, or compound; palmate (with 3–7 lobes). Leaflets ovate, or obovate, or triangular. Leaf blades dissected, or entire; broadly ovate to orbicular; when simple/dissected, palmately lobed; palmately veined; cross-venulate; cordate. Leaves without stipules (tendrils stipular in position). Leaf blade margins entire (and sinuate), or dentate (to denticulate). Leaves without a persistent basal meristem. Leaf anatomy. Hairs present, or absent (may be glabrescent). Extra-floral nectaries absent (ass.).

Reproductive type, pollination. Fertile flowers functionally male and functionally female, or functionally male, or functionally female. Unisexual flowers present. Plants monoecious, or dioecious. Female flowers solitary (mostly), or aggregated in ‘inflorescences’ (rarely); without staminodes. Male flowers aggregated in ‘inflorescences’ (mostly), or solitary (rarely); with pistillodes (reduced to 3 filiform rudiments). Entomophilous.

Inflorescence and flower features. Flowers solitary (usually in female flowers, rarely in male flowers), or aggregated in ‘inflorescences’ (males, mostly); in racemes (male flowers). Inflorescences axillary; racemes pedunculate. Flowers pedicellate; bracteate (most male flowers), or ebracteate; probracts present or absent; small to large; regular; cyclic. Free hypanthium present; urceolate, or turbinate (male flowers more or less funnel-shaped to urceolate or conic; upper part of female flowers more or less funnel-shaped); of female flowers ellipsoidal or ovoid in lower part that contains the ovary. Perianth with distinct calyx and corolla; 10; 2 -whorled; isomerous. Calyx present; 5; 1 -whorled; gamosepalous; blunt-lobed; imbricate, or open in bud; regular. Calyx lobes triangular (to sublate). Corolla present; 5; 1 -whorled; gamopetalous (deeply divided); more or less valvate; rotate; regular; white (or greenish-white). Corolla lobes oblong, or ovate to triangular. Corolla members fringed. Fertile stamens present, or absent. Androecial members definite in number. Androecium 3. Androecial members branched and unbranched, or unbranched; adnate (to the hypanthium); all equal (ass.); free of one another; 1 -whorled. Androecium exclusively of fertile stamens. Stamens 3; distinctly dissimilar in shape (uni/bilocular); reduced in number relative to the adjacent perianth; oppositisepalous (towards mouth of hypanthium, on calyx tube below petals). Anthers separate from one another, or cohering; adnate; dehiscing via longitudinal slits; extrorse; unilocular (1 anther), or bilocular (2 anthers); bisporangiate, or bisporangiate and tetrasporangiate, or tetrasporangiate; appendaged (via the prolonged connective), or unappendaged. Fertile gynoecium present, or absent. Gynoecium 1 carpelled, or 2–5 carpelled. The pistil 1–3 celled. Gynoecium syncarpous; of one carpel, or synovarious, or synstylovarious, or eu-syncarpous; inferior. Ovary unilocular, or plurilocular; 1–3 locular. Gynoecium stylate. Styles 1; partially joined; apical. Stigmas 3; commissural; 2 - lobed. Placentation parietal; when the ovary plurilocular, axile. Ovules in the single cavity 20–50; 20–50 per locule (many); pendulous, or horizontal, or ascending; non-arillate; anatropous.

Fruit and seed features. Fruit (20–)30–140 mm long; 1.5–9 cm in diameter; fleshy (with a hard rind); not spinose; indehiscent; 20–100 seeded (numerous). Seeds non-endospermic; medium sized to large; winged, or wingless. Cotyledons 2 (large, flat). Embryo straight.

Etymology. From the Greek for "hair" and "flower"; the corolla lobes are fringed with long hairs.