| # The Families of Angiosperms |

L. Watson and M.J. Dallwitz

### Calyceraceae R.Br. ex Rich.

Including Boöpidaceae Cass.

Habit and leaf form. Herbs. Plants green and photosynthesizing. Annual to perennial; with a basal aggregation of leaves, or without conspicuous aggregations of leaves. Leaves alternate; simple. Lamina dissected, or entire; when dissected, pinnatifid (pinnately lobed). Leaves exstipulate.

Leaf anatomy. The leaf lamina dorsiventral. Stomata present; on both surfaces; anomocytic. Hairs present, or absent (?); if present, eglandular. Lamina without secretory cavities.

Axial (stem, wood) anatomy. Secretory cavities absent. Primary vascular tissues in a cylinder, without separate bundles; collateral. Cortical bundles absent. Secondary thickening absent, or developing from a conventional cambial ring (?). Primary medullary rays wide.

The vessel end-walls simple. The axial xylem without fibre tracheids; with libriform fibres.

Reproductive type, pollination. Unisexual flowers present, or absent. Plants hermaphrodite (usually), or monoecious, or andromonoecious, or gynomonoecious. Pollination entomophilous; mechanism conspicuously specialized (via an active presentation system, the pollen being released into an anther tube and pushed out by elongation of the style).

Inflorescence, floral, fruit and seed morphology. Flowers aggregated in ‘inflorescences’; in heads. The ultimate inflorescence units racemose (the capitula centripetal). Inflorescences scapiflorous, or not scapiflorous; consisting of involucrate, centripetally flowering heads; with involucral bracts; pseudanthial. Flowers bracteate (the capitulum surrounded by 1–2 series); regular, or somewhat irregular; more or less zygomorphic. The floral irregularity involving the perianth (the corolla). Flowers (4–)5(–6) merous; cyclic; tetracyclic. Free hypanthium absent.

Perianth with distinct calyx and corolla; (8–)10(–12); 2 whorled; isomerous. Calyx (4–)5(–6); 1 whorled; polysepalous, or gamosepalous; lobulate, or blunt-lobed, or toothed; unequal but not bilabiate, or regular; persistent; accrescent, or non-accrescent. Corolla (4–)5(–6); 1 whorled; gamopetalous; valvate, or with open aestivation; somewhat unequal but not bilabiate, or regular; persistent.

Androecium (4–)5(–6). Androecial members adnate (near the top of the corolla tube); coherent (the filaments connate into a tube, at least basally); 1 adelphous; 1 whorled. Androecium exclusively of fertile stamens. Stamens (4–)5(–6); inserted in the throat of the corolla tube; isomerous with the perianth; oppositisepalous. Anthers connivent, or cohering (sometimes, basally); basifixed; non-versatile; dehiscing via longitudinal slits; introrse; tetrasporangiate. Endothecium developing fibrous thickenings. Anther epidermis degenerating. Tapetum glandular. Pollen grains aperturate; 3 aperturate; colporate; 2-celled.

Gynoecium basically 2 carpelled. Carpels reduced in number relative to the perianth. The pistil 1 celled. Gynoecium syncarpous (but pseudomonomerous); eu-syncarpous; inferior. Ovary 1 locular. Epigynous disk present (uniting the base of the corolla to the style, lining the corolla tube and dilating into glandular areolae). Gynoecium stylate. Styles 1; apical. Stigmas 1; capitate. Placentation apical. Ovules in the single cavity 1; pendulous; non-arillate; anatropous; unitegmic; tenuinucellate. Embryo-sac development Polygonum-type. Polar nuclei fusing prior to fertilization. Antipodal cells formed; 3; not proliferating; ephemeral. Synergids elongated, with slender beaks. Endosperm formation cellular.

Fruit non-fleshy; indehiscent; achene-like (crowned by the persistent calyx and corolla). Gynoecia of adjoining flowers combining to form a multiple fruit (often, more or less), or not forming a multiple fruit. The multiple fruits coalescing (sometimes, somewhat), or not coalescing. Fruit 1 seeded. Seeds copiously or scantily endospermic. Endosperm oily. Embryo well differentiated. Cotyledons 2. Embryo straight.

Physiology, phytochemistry. Inulin recorded. Not cyanogenic. Iridoids detected; ‘Route I’ type (normal and seco). Proanthocyanidins absent. Aluminium accumulation not found.

Geography, cytology. Neotropical. Temperate to sub-tropical. South America. X = 8, 15, 18, 21.

Taxonomy. Subclass Dicotyledonae; Tenuinucelli. Dahlgren’s Superorder Corniflorae; Dipsacales. Cronquist’s Subclass Asteridae; Calycerales. APG III core angiosperms; core eudicot; Superorder Asteranae; campanulid. APG IV Order Asterales.

Species 40. Genera 6; Acicarpha, Boöpis, Calycera, Gamocarpha, Moschopsis, Nastanthus.

Illustrations. • Le Maout and Decaisne: Calycera. • Calycera crassifolia (as Boopis): Hook. Ic. Pl. 18 (1888).

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: 8th June 2026. delta-intkey.com’.

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