Family Lepuropetalaceae

Lepuropetalaceae (Engl.) Nak.

~ Celastraceae, Saxifragaceae sensu lato, Parnassiaceae

Habit and leaf form. Diminutive herbs (with leaves brown-streaked from tannins). Plants more or less succulent. Annual. Leaves (sub) opposite, or alternate; simple. Lamina entire. Leaves exstipulate.

Stem anatomy. Secondary thickening absent (?).

Reproductive type, pollination. Plants hermaphrodite.

Inflorescence, floral, fruit and seed morphology. Flowers solitary; terminal; ebracteolate; regular; 5 merous; cyclic; tetracyclic, or pentacyclic.

Perianth with distinct calyx and corolla, or sepaline (the corolla minute or missing); 5–10; 1 whorled, or 2 whorled. Calyx 5; 1 whorled; polysepalous; regular. Corolla when present, 1–5; 1 whorled; when recognisable, polypetalous (the petals tiny, round to spathulate).

Androecium 10. Androecial members free of the perianth and adnate; free of one another; 2 whorled. Androecium including staminodes. Staminodes 5; external to the fertile stamens (constituting an outer, epipetalous whorl). Stamens 5; isomerous with the perianth; oppositisepalous (very short). Pollen grains aperturate; 3 aperturate; colporate.

Gynoecium 3–4 carpelled. Carpels reduced in number relative to the perianth. The pistil 1 celled. Gynoecium syncarpous; synovarious; inferior. Ovary 1 locular. Gynoecium stylate. Styles 3–4; free; shorter than the ovary (very short). Stigmas 3; commissural (along with the styles); capitate. Placentation parietal. Ovules in the single cavity 30–100 (‘many’).

Fruit non-fleshy; dehiscent; a capsule (globose, thin-walled). Capsules loculicidal. Seeds scantily endospermic (the endosperm layer one cell thick). Perisperm absent.

Geography, cytology. Holarctic and Neotropical. Southern U.S.A., Mexico, Chile.

Taxonomy. Subclass Dicotyledonae; Crassinucelli (? — apetalous or polypetalous). Dahlgren’s Superorder Theiflorae; Droserales. Cronquist’s Subclass Rosidae; Rosales. APG 3 core angiosperms; core eudicot; Superorder Rosanae; fabid; Order Celastrales (as a synonym of Celastraceae).

Species 1. Genera 1; Lepuropetalon.

Cf. Parnassiaceae.