The families of flowering plants

L. Watson and M. J. Dallwitz

Basellaceae Moq.-Tand.

Including Anredereae (Anrederaceae) J.G. Argardh, Ullucaceae Nak.

Habit and leaf form. Herbs. Perennial; with a basal aggregation of leaves, or without conspicuous aggregations of leaves; rhizomatous, or tuberous. Self supporting, or climbing; the climbers stem twiners, or scrambling. Mesophytic. Leaves opposite, or alternate; somewhat fleshy; petiolate; non-sheathing; simple. Lamina entire; pinnately veined to palmately veined; cross-venulate. Leaves exstipulate.

Leaf anatomy. Stomata present; on both surfaces; paracytic, or anomocytic and paracytic. Hairs said to be absent. The mesophyll containing mucilage cells; containing crystals. The crystals druses (usually), or druses and solitary-prismatic. Minor leaf veins without phloem transfer cells (Basella).

Axial (stem, wood) anatomy. Cork cambium present (sometimes?), or absent; initially superficial. Primary vascular tissues comprising a ring of bundles (these of unequal size); bicollateral, or collateral and bicollateral (at least in the larger bundles bicollateral). Internal phloem present (at least in stems with large bundles). Secondary thickening absent, or developing from a conventional cambial ring (?).

The vessel end-walls simple. ‘Included’ phloem absent.

Reproductive type, pollination. Plants hermaphrodite (mostly), or monoecious (? — at least sometimes ‘functionally unisexual’).

Inflorescence, floral, fruit and seed morphology. Flowers aggregated in ‘inflorescences’; in racemes, or in spikes, or in panicles. Inflorescences terminal, or axillary; panicles, racemes or spikes. Flowers bracteate (the bracts small); bracteolate (the two bracteoles calyx-like, connate at the base or not, often winged and persistent in the fruit); regular (excluding paired bracteoles); 5 merous; cyclic; tricyclic, or tetracyclic (if the bracteoles regarded as ‘perianth’). Floral receptacle not markedly hollowed. Free hypanthium present. Hypogynous disk present; annular.

Perianth with distinct calyx and corolla (if the bracteoles are regarded as calyx, the calyx as corolla), or sepaline (the best interpretation?), or petaline; 5, or 7 (if the ‘bracteoles’ are mistaken for perianth); 1 whorled, or 2 whorled (if the bracteoles are included); anisomerous (if the bracteoles included); persistent. Calyx 5 (i.e. the true perianth), or 2 (i.e. the bracteoles); polysepalous (the true sepals and/or the bracteoles sometimes almost distinct), or gamosepalous (the bracteoles and/or the true sepals usually tubular below); persistent (both the bracteoles and the true calyx); imbricate.

Androecium 5. Androecial members adnate (to the base of the perianth members, or to the tube); free of one another; 1 whorled. Androecium exclusively of fertile stamens. Stamens 5; isomerous with the perianth; oppositisepalous; bent outwards in bud. Anthers dorsifixed; versatile; dehiscing via pores, or dehiscing via short slits, or dehiscing via longitudinal slits; tetrasporangiate. Microsporogenesis simultaneous. Tapetum glandular. Pollen shed as single grains. Pollen grains aperturate; foraminate, or rugate (pantocolpate, or cuboid with a colpus on each furrow); spinulose; 3-celled (Andredera).

Gynoecium 3 carpelled. Carpels reduced in number relative to the perianth. The pistil 1 celled (when mature). Gynoecium syncarpous; synovarious to eu-syncarpous; superior. Ovary 1 locular (though detectably trilocular in the very early stages of development). Gynoecium stylate. Styles 1, or 3; when separate, free, or partially joined; apical. Stigmas 3. Placentation basal. Ovules in the single cavity (of the mature ovary) 1; funicled; ascending; non-arillate; anatropous to campylotropous; bitegmic; crassinucellate. Outer integument contributing to the micropyle. Embryo-sac development Polygonum-type. Polar nuclei fusing prior to fertilization. Antipodal cells formed; 3; not proliferating; ephemeral. Synergids pear-shaped. Endosperm formation nuclear.

Fruit non-fleshy; indehiscent; capsular-indehiscent (a utricle); enclosed in the fleshy perianth, or without fleshy investment external to the original ovary (then surrounded by the winged bracteoles). Seeds non-endospermic. Perisperm present. Seeds with starch. Embryo well differentiated. Cotyledons 2. Embryo chlorophyllous; curved (semi-annular), or coiled.

Seedling. Germination phanerocotylar.

Physiology, phytochemistry. Anatomy non-C4 type (Basella). Not cyanogenic. Iridoids not detected. Betalains present. Proanthocyanidins absent. Flavonols present, or absent; when present, quercetin. Ellagic acid absent (2 genera, 2 species). Sieve-tube plastids P-type; type III (a).

Geography, cytology. Tropical. Tropical America, Africa, Asia. X = 11, 12.

Taxonomy. Subclass Dicotyledonae; Crassinucelli. Dahlgren’s Superorder Caryophylliflorae; Caryophyllales. Cronquist’s Subclass Caryophyllidae; Caryophyllales. APG 3 core angiosperms; core eudicot; Superorder Caryophyllanae; Order Caryophyllales.

Species 25. Genera 4; Anredera, Basella, Tournonia, Ullucus.

Illustrations. • Technical details: Anredera, Basella, Ullucus.

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: 19th October 2016.’.