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The families of flowering plants

L. Watson and M.J. Dallwitz

Tepuianthaceae Maguire & Steyermark

~ Thymelaeaceae.

Habit and leaf form. Trees and shrubs; resinous. Leaves alternate, or opposite; ‘herbaceous’ to leathery; petiolate; non-sheathing; gland-dotted; simple. Lamina entire; oblanceolate, or oblong, or obovate (or spathulate); pinnately veined; cross-venulate. Leaves exstipulate.

Axial (stem, wood) anatomy. The vessel end-walls simple.

Reproductive type, pollination. Plants androdioecious.

Inflorescence, floral, fruit and seed morphology. Flowers aggregated in ‘inflorescences’; in cymes. The ultimate inflorescence units cymose. Inflorescences terminal, or axillary. Flowers small; regular; cyclic. Free hypanthium absent. Hypogynous disk present; extrastaminal; of separate members (these contiguous).

Perianth with distinct calyx and corolla; 10; 2 whorled; isomerous. Calyx 5; 1 whorled; polysepalous; imbricate. Corolla 5; 1 whorled; polypetalous; imbricate; regular. Petals more or less clawed.

Androecium 5–15. Androecial members free of the perianth; free of one another; 1–3 whorled. Androecium exclusively of fertile stamens. Stamens 5–15; isomerous with the perianth, or diplostemonous, or triplostemonous; oppositisepalous; alternating with the corolla members, or both alternating with and opposite the corolla members. Anthers sagittate; tetrasporangiate. Pollen shed as single grains. Pollen grains aperturate; 3 aperturate; colporate.

Gynoecium 3 carpelled. Carpels reduced in number relative to the perianth. The pistil 3 celled. Gynoecium syncarpous; synovarious; superior. Ovary 3 locular. Gynoecium stylate. Styles free (short, bifid). Placentation axile. Ovules 1 per locule; pendulous; non-arillate; anatropous.

Fruit non-fleshy; dehiscent; a capsule. Capsules bony loculicidal. Fruit 3 seeded. Seeds endospermic. Embryo weakly differentiated. Cotyledons 2 (poorly differentiated).

Geography, cytology. Neotropical. Guayana Highlands.

Taxonomy. Subclass Dicotyledonae; Crassinucelli (?). Dahlgren’s Superorder Santaliflorae (?); Celastrales (?). Cronquist’s Subclass Rosidae (?); Celastrales (?). APG III core angiosperms; core eudicot; Superorder Rosanae; malvid. APG IV Order Malvales (as a synonym of Thymelaeaceae).

Species 5. Genera 1; Tepuianthus.

General remarks. See Maguire & Steyermark (1981), Mem. New York Bot. Gard. 32: 12. The description seen is very inadequate, and taxonomic assignment is uncertain. It depicts Tepuianthus as differing from Thymelaeaceae in the cymose inflorescence, floral morphology (no hypanthium, synovarious gynoecium, non-arillate ovules) and dehiscent-capsular fruits.

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: 15th April 2018.’.