Zehneria Endl.

Scientific Description

Family Cucurbitaceae.

Habit and leaf form. Herbs, or herbaceous climbers (or trailing). Annual, or perennial. Leaves cauline (ass.). Plants with neither basal nor terminal concentrations of leaves. Stem internodes solid (ass.). Climbing (or trailing); tendril climbers (simple, coiled distally). Tendrils simple. Mesophytic to xerophytic. Leaves alternate; spiral; petiolate; non-sheathing; simple. Leaf blades dissected (shallowly 3–5 lobed), or entire; ovate (broadly); when simple/dissected, palmately lobed; palmately veined; cross-venulate; cordate, or hastate (cordate to hastate). Leaves without stipules (tendrils stipular in position). Leaf blade margins entire, or dentate (sinuate-dentate). Leaves without a persistent basal meristem. Leaf anatomy. Hairs present, or absent; glandular hairs absent, or present. Extra-floral nectaries present (on bracts of male flowers).

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, or aggregated in ‘inflorescences’; with staminodes (3 staminodes). Male flowers aggregated in ‘inflorescences’; without pistillodes (ass.). Entomophilous.

Inflorescence and flower features. Flowers solitary (female flowers, sometimes), or aggregated in ‘inflorescences’ (males and females); in racemes, or in heads, or in umbels, or in fascicles (or paired). Inflorescences axillary; male flowers in racemes, fascicles, or pedunculate heads, rarely solitary; female flowers in racemes, fascicles or solitary. Flowers pedicellate (in male flowers pedicels have small glandular bracts); bracteate (male flowers); ebracteolate (ass.); small to large; regular; cyclic. Free hypanthium present; campanulate (in male flowers), or urceolate (in female flowers, the lower part narrowed into a short neck and expanded into a campanulate upper part); glabrous, in female flowers the lower part adnate to 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, or ovate (to subulate). Corolla present; 5; 1 -whorled; deeply gamopetalous; more or less valvate; regular; white, or yellow. Corolla lobes ovate to triangular. Fertile stamens present, or absent. Androecial members definite in number. Androecium 2–4. Androecial members branched and unbranched, or unbranched; adnate (to the hypanthium); all equal (ass.); free of one another, or coherent; when coherent, commonly 1 - adelphous (i.e. all the stamens joined in a central column), or 2 - adelphous (4/1 in Thladiantha); 1 -whorled. Androecium exclusively of fertile stamens. Stamens 2–4; all more or less similar in shape; isomerous with the perianth; oppositisepalous (about the middle of the hypanthium, on the calyx tube below the petals). Anthers cohering, or connivent, or separate from one another; adnate; dehiscing via longitudinal slits; extrorse; bilocular; 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 1; commissural; (2–)3 - lobed. Placentation parietal; when the ovary plurilocular, axile. Ovules in the single cavity 5–50; 5–50 per locule (few to many); pendulous, or horizontal, or ascending; non-arillate; anatropous.

Fruit and seed features. Fruit 8–25 mm long; 0.6–1.2 cm in diameter (orbicular or ellipsoidal); fleshy; not spinose; indehiscent; few to many. Seeds non-endospermic; medium sized to large; winged, or wingless. Cotyledons 2 (large, flat). Embryo straight.

Etymology. After Joseph Zehner, botanical artist.