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The families of flowering plants

L. Watson and M.J. Dallwitz

Cyanastraceae Engl.

~ Tecophilaeaceae.

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.

Leaf anatomy. Stomata present; paracytic. Lamina with secretory cavities. Secretory cavities containing oil; schizogenous. The mesophyll containing crystals, or without crystals. The crystals if present, raphides. Foliar vessels absent. Minor leaf veins without phloem transfer cells.

Axial (stem, wood) anatomy. Secondary thickening absent. The axial 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, phytochemistry. Accumulated starch other than exclusively ‘pteridophyte type’. 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 III core angiosperms; Superorder Lilianae; non-commelinid Monocot. APG IV Order Asparagales (as a synonym of Tecophilaeaceae).

Species 6. Genera 1; only genus, Cyanastrum.

General remarks. Comparing descriptions with Intkey shows Cyanastrum differing from Tecophilaeaceae (q.v.) in numerous characters involving leaf anatomy, as well as floral, fruit and seed morphology.

Illustrations. • Cyanastrum cordifolium: Hook. Ic. Pl. 20 (1891).

We advise against extracting comparative information from the descriptions. This is much more easily achieved using the DELTA data files or the interactive key, which allows access to the character list, illustrations, full and partial descriptions, diagnostic descriptions, differences and similarities between taxa, lists of taxa exhibiting or lacking specified attributes, distributions of character states within any set of taxa, geographical distribution, genera included in each family, and classifications (Dahlgren; Dahlgren, Clifford, and Yeo; Cronquist; APG). See also Guidelines for using data taken from Web publications.

Cite this publication as: ‘Watson, L., and Dallwitz, M.J. 1992 onwards. The families of flowering plants: descriptions, illustrations, identification, and information retrieval. Version: 5th March 2018.’.