| # The Families of Angiosperms |

L. Watson and M.J. Dallwitz

### Henriqueziaceae (Hook. f.) Bremek.

~ Rubiaceae.

Habit and leaf form. Small or medium trees. Leaves alternate, or whorled; simple. Lamina entire. Leaves stipulate. Stipules without colleters. Lamina margins entire.

General anatomy. Plants with ‘crystal sand’.

Leaf anatomy. The leaf lamina dorsiventral.

Axial (stem, wood) anatomy. Internal phloem absent. Secondary thickening developing from a conventional cambial ring. Primary medullary rays narrow.

The parenchyma mainly paratracheal (aliform to confluent). ‘Included’ phloem absent.

Reproductive type, pollination. Unisexual flowers absent. Plants hermaphrodite.

Inflorescence, floral, fruit and seed morphology. Flowers aggregated in ‘inflorescences’; in panicles (thyrses). The ultimate inflorescence units cymose. Inflorescences terminal; terminal thyrses. Flowers large; very irregular; zygomorphic; cyclic; tetracyclic. Free hypanthium absent.

Perianth with distinct calyx and corolla; 9–10; 2 whorled; isomerous, or anisomerous. Calyx 4–5; 1 whorled; polysepalous (?); not persistent. Corolla 5; 1 whorled; gamopetalous; imbricate; campanulate; bilabiate.

Androecium 5. Androecial members adnate (epipetalous); markedly unequal (the filaments curved); free of one another; 1 whorled. Androecium exclusively of fertile stamens. Stamens 5; isomerous with the perianth; oppositisepalous; alternating with the corolla members; filantherous (the filaments bent at the base). Anthers dorsifixed (the base sagittate); dehiscing via longitudinal slits; introrse. Pollen grains aperturate; 5–6 aperturate; colpate.

Gynoecium 2 carpelled. Carpels reduced in number relative to the perianth. The pistil 2 celled. Gynoecium syncarpous; synstylovarious; inferior. Ovary 2 locular. Epigynous disk present (annular). Gynoecium stylate. Styles 1; apical. Stigmas 2. Placentation axile. Ovules 2–4 per locule; collateral.

Fruit non-fleshy; dehiscent; a capsule. Capsules loculicidal (semi-superior or almost superior, transversely ovoid, subreniform or discoid). Fruit 2–4 seeded. Seeds non-endospermic; wingless (but flattened).

Geography, cytology. Neotropical. Tropical. Brazil.

Taxonomy. Subclass Dicotyledonae; Tenuinucelli. Dahlgren’s Superorder Lamiiflorae; Scrophulariales. Cronquist’s Subclass Asteridae; Rubiales. APG III core angiosperms; core eudicot; Superorder Asteranae; lamiid. APG IV Order Gentianales (as a synonym of Rubiaceae).

Species 13. Genera 2; Henriquezia, Platycarpum.

General remarks. Seemingly differing from Rubiaceae in the large, very iregular, campanulate flowers and lack of inulin; but this description is inadequate, and the extent of intra-taxon within the large family may be under-estimated in the present compilation.

Illustrations. • Henriquezia verticillata: Bentham, Trans. Lin. Soc. Bot. 22 (1859). • Henriquezia verticillata (as obovata), fruit details: Bentham, Trans. Lin. Soc. Bot. 22 (1859). • Henriquezia verticillata: Nat. Pflanzenfam. IV (1895). • Henriquezia jenmanii: Cheeseman, Trans. Bot. Linn. Soc. 6 (1901).

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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