Tetracarpaeaceae (Engl.) Nak.
~ Escalloniaceae, Grossulariaceae, Saxifragaceae
Habit and leaf form. Low shrubs. Plants non-succulent. Leptocaul. Mesophytic. Leaves evergreen; small; alternate; leathery; petiolate; non-sheathing; not gland-dotted; simple. Lamina entire; oblong, or ovate; pinnately veined; cross-venulate. Leaves exstipulate. Lamina margins doubly serrate. Leaves without a persistent basal meristem.
Stem anatomy. Internal phloem absent. Secondary thickening developing from a conventional cambial ring. ‘Included’ phloem absent.
Reproductive type, pollination. Unisexual flowers absent. Plants hermaphrodite.
Inflorescence, floral, fruit and seed morphology. Flowers aggregated in ‘inflorescences’; in racemes. The terminal inflorescence unit racemose. Inflorescences terminal; erect racemes. Flowers bracteate; small; regular; 4–5 merous; cyclic; pentacyclic. Free hypanthium present (?— with a short ‘calyx tube’).
Perianth with distinct calyx and corolla; 8, or 9; 2 whorled; isomerous, or anisomerous. Calyx 4, or 5; 1 whorled; shortly gamosepalous (basally). Calyx lobes markedly longer than the tube. Calyx regular; persistent; imbricate. Corolla 4; 1 whorled; polypetalous; imbricate; regular; white; deciduous (caducous). Petals clawed.
Androecium 8. Androecial members free of the perianth; coherent; 1 adelphous (the filaments very shortly connate); 2 whorled. Androecium exclusively of fertile stamens. Stamens 8; diplostemonous; both alternating with and opposite the corolla members. Anthers basifixed; non-versatile; dehiscing via longitudinal slits; latrorse. Pollen grains aperturate; 3 aperturate; colpate (?).
Gynoecium 4 carpelled. Carpels isomerous with the perianth. Gynoecium apocarpous; eu-apocarpous; superior. Carpel sub non-stylate; apically stigmatic; 15–100 ovuled (‘many’). Placentation marginal (ventral). Ovules anatropous; unitegmic.
Fruit fleshy; an aggregate. The fruiting carpel dehiscent; a follicle. Fruit 15–100 seeded (‘many’). Seeds endospermic.
Geography, cytology. Temperate. Tasmania.
Taxonomy. Subclass Dicotyledonae; Crassinucelli, or Tenuinucelli (? — polypetalous, but exstipulate and ovules unitegmic). Dahlgren’s Superorder Corniflorae (?); Cornales (?). Cronquist’s Subclass Rosidae; Rosales. APG (1998) Eudicot; core Eudicot; Rosid; Saxifragales. Species 1. Genera 1; only genus, Tetracarpaea.
Cite this publication as: ‘L. Watson and M. J. Dallwitz (1992 onwards). The Families of Flowering Plants: Descriptions, Illustrations, Identification, and Information Retrieval. Version: 14th December 2000. http://biodiversity.uno.edu/delta/’. Dallwitz (1980), Dallwitz, Paine and Zurcher (1993, 1995, 2000), and Watson and Dallwitz (1991) should also be cited (see References).