Family Flagellariaceae

Flagellariaceae Dum.

Habit and leaf form. Lianas (with dichotomous branching from sympodial rhizomes). Perennial; with neither basal nor terminal aggregations of leaves; rhizomatous (these sympodial). High climbing (the stems canelike); tendril climbers (the tendrils representing modification of the lamina tips). Stem growth conspicuously sympodial (frequently with equal dichotomies above). Mesophytic. Leaves alternate; distichous; petiolate; sheathing. Leaf sheaths with joined margins. Leaves simple. Lamina entire; lanceolate; parallel-veined; without cross-venules. Leaves eligulate. Lamina margins entire. Leaves with a persistent basal meristem, and basipetal development. Vernation convolute (below), or circinnate (at the tips); apically circinnate.

General anatomy. Plants with silica bodies (globose, in the fibrous tissue associated with the vascular bundles). Chlorenchyma without ‘peg cells’. Accumulated starch other than exclusively ‘pteridophyte type’.

Leaf anatomy. Epidermis without differentiation into ‘long’ and ‘short’ cells; without silica bodies. Guard-cells ‘grass type’.

Lamina dorsiventral, or isobilateral; with secretory cavities (in the mesophyll). The mesophyll without calcium oxalate crystals (? — no raphides). Vessels present; end-walls scalariform and simple (mostly scalariform).

Stem anatomy. Stems with solid internodes. Young stems cylindrical. Secretory cavities absent. Cork cambium absent. Secondary thickening absent. Xylem with vessels. Vessel end-walls scalariform and simple (mostly simple). Sieve-tube plastids P-type; type II.

Reproductive type, pollination. Unisexual flowers absent. Plants hermaphrodite. Floral nectaries absent (nectaries lacking). Pollination probably anemophilous.

Inflorescence, floral, fruit and seed morphology. Flowers aggregated in ‘inflorescences’; in panicles; not in ‘spikelets’. Inflorescences terminal; panicles. Flowers bracteate; 3 merous; cyclic; pentacyclic. Perigone tube absent. Hypogynous disk absent.

Perianth of ‘tepals’; 6; free; 2 whorled (3+3); isomerous; petaloid; similar in the two whorls (equal or subequal); white.

Androecium 6. Androecial members free of the perianth; free of one another; 2 whorled. Androecium exclusively of fertile stamens, or including staminodes. Staminodes 1–3 (?). Stamens (3–)6; reduced in number relative to the adjacent perianth to diplostemonous. Anthers sagittate basifixed; non-versatile; dehiscing via longitudinal slits; latrorse; tetrasporangiate. The endothecial thickenings girdling. Microsporogenesis successive. The initial microspore tetrads isobilateral, or linear. Pollen grains aperturate; 1 aperturate; ulcerate. The ulcus without an operculum (or this vestigial, represented by coarse granules or exine fragments); with an annulus. Interapertural exine scrobiculate. Interapertural interstitium columellate. Pollen grains 2-celled.

Gynoecium 3 carpelled. Carpels isomerous with the perianth. The pistil 3 celled. Gynoecium syncarpous; synovarious to synstylovarious; superior. Ovary 2 locular. Styles 3 (sometimes connate basally); free, or partially joined; apical. Stigmas 3 (the styles stigmatic for almost their entire lengths); dry type; papillate; Group II type. Placentation axile. Ovules 1 per locule; pendulous; non-arillate; orthotropous; crassinucellate. Outer integument not contributing to the micropyle (?). Embryo-sac development Allium-type. Antipodal cells formed; 3; not proliferating. Synergids non-haustorial. Embryogeny onagrad, or asterad.

Fruit fleshy; indehiscent; a drupe (red or black). The drupes with one stone. Seeds copiously endospermic. Endosperm not oily (starchy). Seeds with starch. Embryo rudimentary at the time of seed release (minute, capping the endosperm). Testa without phytomelan; membranous.

Physiology, biochemistry. Alkaloids present, or absent (2 species examined). Proanthocyanidins absent. Flavonols present; kaempferol. Ellagic acid absent.

Geography, cytology. Sub-tropical to tropical. Africa, southeast Asia and Malaysia, northeast Australia. 2n = 38.

Taxonomy. Subclass Monocotyledonae. Dahlgren et al. Superorder Commeliniflorae; Poales. APG 3 core angiosperms; Superorder Lilianae; commelinid Monocot; Order Poales.

Species 4. Genera 1; only genus, Flagellaria.