Family Eriospermaceae

Eriospermaceae Endl.

~ Formerly Liliaceae-Asphodeleae-Eriosperminae, Asparagaceae-Nolinoideae according to APG



Habit and leaf form. Herbs. ‘Normal’ plants, or plants of very peculiar vegetative form (in that the leaves are confined to a few basal scales, plus one or 2–3 (rarely more) basally concentrated laminate leaves); when ‘very peculiar’, more or less neotenic. Perennial; tuberous (with a single plump tuber, or a complex of tubers and stolons, the tubers containing white, yellow, pink or red mucilage). Xerophytic. Leaves small to medium-sized; alternate; spiral; petiolate to sessile; sheathing; simple. Lamina entire; linear, or lanceolate, or oblong to ovate; parallel-veined; cross-venulate; cordate, or attenuate at the base. Leaves eligulate (but frequently curiously appendaged at the base of the blade, the appendage variously of filiform threads, bottlebrush shaped or like a bunch of feathers, or sometmes much-branched with thick, linear, fleshy segments, and the blade often relatively small in proportion). Lamina margins entire.

Leaf anatomy. Hairs present, or absent.

The mesophyll containing calcium oxalate crystals. The mesophyll crystals raphides.

Stem anatomy. Secondary thickening absent.

Reproductive type, pollination. Plants hermaphrodite.

Inflorescence, floral, fruit and seed morphology. Flowers aggregated in ‘inflorescences’; in racemes, or in panicles. Inflorescences scapiflorous (the scape with or without scales); racemes or panicles, often sparse, developing in summer after the assimilatory leaves have withered. Flowers bracteate (often long pedicelled); regular; 3 merous; cyclic; pentacyclic. Perigone tube absent. Hypogynous disk absent.

Perianth of ‘tepals’; 6; free; 2 whorled; isomerous; petaloid; similar in the two whorls; white, or cream, or yellow, or pink; persistent (the outer members upright or spreading).

Androecium 6. Androecial members adnate (to the bases of the tepals); free of one another; 2 whorled. Androecium exclusively of fertile stamens. Stamens 6; diplostemonous. Anthers dorsifixed; dehiscing via longitudinal slits; introrse. The endothecial thickenings spiral. Microsporogenesis successive. Tapetum glandular. Pollen grains aperturate; 1 aperturate; probably sulcate.



Gynoecium 3 carpelled. Carpels isomerous with the perianth. The pistil 3 celled. Gynoecium syncarpous; eu-syncarpous; superior. Ovary 3 locular; sessile. Gynoecium stylate. Styles 1; apical. Stigmas 1 (small, subcapitate or minutely trilobed). Placentation axile. Ovules 2–4 per locule (‘the cells few-ovuled’); funicled; ascending; non-arillate; anatropous; bitegmic; weakly crassinucellate. Embryo-sac development Polygonum-type. Endosperm formation nuclear (?). Embryogeny solanad (the embryology unusual, with nucellar tissue enveloping the chalazal parts of the embryo).

Fruit non-fleshy; dehiscent; a capsule (thin walled). Capsules loculicidal, or septicidal and loculicidal. Seeds non-endospermic; conspicuously hairy (uniquely among monocots — the hairs to 8 mm long, silky, white or reddish brown, bent back to the chalaza). Embryo well differentiated (conical-cylindrical). Cotyledons 1. Testa hairy; without phytomelan.

Geography, cytology. Paleotropical and Cape. Africa, especially southern Africa.


Taxonomy. Subclass Monocotyledonae. Dahlgren et al. Superorder Liliiflorae; Asparagales. APG 3 core angiosperms; Superorder Lilianae; non-commelinid Monocot; Order Asparagales (as a synonym of Asparagaceae).

Species 80. Genera 1; only genus, Eriospermum.


Illustrations.
• Technical details (Eriospermum).
• Eriospermum folioliferum: Bot. Reg. 795, 1824.

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