The families of flowering plants

L. Watson and M.J. Dallwitz

Gerrardinaceae M.H. Alford

~ Flacourtiaceae.

Habit and leaf form. Small trees, or shrubs (sometimes scandent). Self supporting, or climbing; when climbing, merely scrambling. Mesophytic. Leaves alternate; flat; not gland-dotted; simple. Lamina entire; pinnately veined. Leaves stipulate. Lamina margins serrate (or double serrate; teeth cunonioid, i.e. with a branching vein extending to the sinus and the tooth apex, the apex glandular but non-spherical and non-torus-shaped); flat.

Leaf anatomy. Epidermis without crystal idioblasts. Mucilaginous epidermis present. The mesophyll containing crystals. The crystals druses.

Axial (stem, wood) anatomy. Secondary thickening developing from a conventional cambial ring.

The axial xylem including septate fibres.

Reproductive type, pollination. Plants hermaphrodite. Floral nectaries present. Nectar secretion from the disk.

Inflorescence, floral, fruit and seed morphology. Flowers aggregated in ‘inflorescences’; in cymes (raceme-like, few-flowered). Inflorescences axillary. Flowers regular; 5 merous; tetracyclic. Free hypanthium present. Hypogynous disk present; intrastaminal (lobed between the stamens); annular.

Perianth with distinct calyx and corolla; 10; 2 whorled; isomerous. Calyx 5; 1 whorled; polysepalous; persistent; imbricate. Corolla 5; 1 whorled; polypetalous; regular; deciduous. Petals sessile; entire.

Androecium 5. Androecial members free of the perianth; all equal; free of one another; 1 whorled. Stamens 5; isomerous with the perianth; alternisepalous; opposite the corolla members. Anthers basifixed; dehiscing via longitudinal slits; introrse. Pollen grains aperturate; 3 aperturate; colporate.

Gynoecium 2 carpelled. Carpels reduced in number relative to the perianth. The pistil 1 celled. Gynoecium syncarpous; eu-syncarpous; superior, or partly inferior (apparently due to being recessed in the receptacle). Ovary 1 locular; sessile. Gynoecium stylate. Styles 1; attenuate from the ovary; apical. Stigmas 1 (-2); 2 lobed (obscurely); capitate (or subcapitate, obscurely 2-lobed). Placentation apical. Ovules in the single cavity 4; pendulous; anatropous.

Fruit fleshy, or non-fleshy; indehiscent; a berry (sometimes dry). Seeds endospermic (?). Testa smooth.

Physiology, phytochemistry. Not cyanogenic.

Geography, cytology. Paleotropical, Cape. Sub-tropical, tropical. Southern and eastern Africa.

Taxonomy. Subclass Dicotyledonae; Crassinucelli (? - referred tentatively, cf. Flacourtiaceae). Dahlgren’s Superorder Violiflorae; Violales. APG 3 core angiosperms; core eudicot; Superorder Rosanae; malvid; Order Huertiales.

Species 2. Genera 1; Gerrardina.

General remarks. See Alford 2006, Taxon 55, 959–964. Differing from the generally similar Flacoutiaceae-Homalieae in the apical ovary placentation, small embryo, cunonioid leaf teeth and introrse anthers. Unsatisfactory molecular analysis has suggested Eurosids II near Sapindales. The current description is inadequate, lacking information on wood anatomy, embryology, cytology and chemistry.

Quotations Description encoded by T.D. Macfarlane, March 2009.

Illustrations. • Gerrardina foliosa: Hook. Ic. Pl. (1867–71).

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: 13th March 2017.’.