Habit and leaf form. Herbs. Perennial; with a basal aggregation of leaves (the leaves few, the lowest bractlike, the upper one or more laminate); cormous (the corms thick, constricted at intevals). Leaves alternate; when laminate, petiolate, or sessile; sheathing; simple. Lamina entire; lanceolate, or ovate; pinnately veined, or palmately veined, or parallel-veined; cross-venulate; cordate, or cuneate at the base. Lamina margins entire.
General anatomy. Accumulated starch other than exclusively ‘pteridophyte type’.
Leaf anatomy. Stomata present; paracytic.
Lamina with secretory cavities. Secretory cavities containing oil; schizogenous. The mesophyll containing calcium oxalate crystals, or without calcium oxalate crystals. The mesophyll crystals if present, raphides. Minor leaf veins without phloem transfer cells. Vessels absent.
Stem anatomy. Secondary thickening absent. Xylem without vessels.
Root anatomy. Root xylem with vessels (perforation plates scalariform).
Reproductive type, pollination. Plants hermaphrodite. Floral nectaries present, or absent (? — no septal nectaries, according to Rudall and Cutler (1995), this conflicting with previous claims).
Inflorescence, floral, fruit and seed morphology. Flowers aggregated in ‘inflorescences’; in racemes, or in panicles. Inflorescences scapiflorous; terminal; panicles, thyrses or racemes; spatheate, or espatheate (the scape subtended basally by a spathelike or bractlike cataphyll). Flowers medium-sized; regular; 3 merous; cyclic; pentacyclic. Perigone tube present. Hypogynous disk absent.
Perianth of ‘tepals’; 6; joined; 2 whorled; isomerous; petaloid; similar in the two whorls; blue.
Androecium 6. Androecial members adnate (inserted at the mouth of the perianth tube); free of one another; 2 whorled. Androecium exclusively of fertile stamens. Stamens 6; filantherous (the filaments short, often S-shaped). Anthers basifixed; non-versatile; dehiscing via pores, or dehiscing via short slits (apically, the thecae with a common opening). Microsporogenesis simultaneous. Tapetum glandular. Pollen grains aperturate; 1 aperturate; sulcate (or trichotomosulcate).
Gynoecium 3 carpelled. The pistil 6 celled. Gynoecium syncarpous; synstylovarious, or eu-syncarpous (?); partly inferior. Ovary 3 locular (deeply lobed, the locules separated cf. Boraginaceae). Gynoecium stylate. Styles 1; from a depression at the top of the ovary; more or less ‘gynobasic’. Stylar canal present. Stigmas 1, or 3 (short). Placentation basal. Ovules 2 per locule (one per locellus); funicled; ascending; with a funicular obturator; anatropous; bitegmic; crassinucellate, or pseudocrassinucellate (?). Embryo-sac development probably Polygonum-type. Endosperm formation nuclear, or helobial (?).
Fruit non-fleshy (membranous); a schizocarp. Mericarps 3; capsular. Fruit usually 1 seeded. Seeds non-endospermic (but with a well developed, starchy chalazosperm). Seeds with starch. Embryo well differentiated. Cotyledons 1. Testa without phytomelan.
Physiology, biochemistry. Not cyanogenic. Proanthocyanidins absent. Flavonols absent. Ellagic acid absent.
Geography, cytology. Paleotropical. Tropical. Tropical Africa. X = 11, 12.
Taxonomy. Subclass Monocotyledonae. Dahlgren et al. Superorder Liliiflorae; Asparagales. APG 3 core angiosperms; Superorder Lilianae; non-commelinid Monocot; Order Asparagales (as a synonym of Tecophilaeaceae).
Species 6. Genera 1; only genus, Cyanastrum.