Sphaerosepalaceae

Abstract

Trees, sometimes tall, or shrubs. Leaves alternate, petiolate, deciduous, entire, pubescent or glabrous, with palmate or pinnate venation. Stipules fused, intrapetiolar, enclosing vegetative buds, caducous, leaving semicircular to annular scars. Inflorescences terminal or on short axillary shoots, paniculate or with cymose partial inflorescences; bracts caducous. Flowers pedicellate, actinomorphic, hermaphrodite, hypogynous. Sepals usually 4, free, imbricate, in 2 pairs, the outer smaller, concave to almost spherical, pubescent on the abaxial surface. Petals usually 4, free, imbricate, obovate. Stamens numerous, distinct or shortly connate at base; filaments filiform, usually curved in bud; anthers dorsifixed, dithecal, longitudinally dehiscent. Receptaculum slightly elevated, usually forming a short gynophore with glabrous, annular disk. Gynoecium syncarpous, either of 4 distinct ovarioles, surrounding a central, gynobasic style, or consisting of a single (1)2(–5)-locular ovary tapering into a terminal style; ovary pubescent; ovules basal, ascendent, anatropous, 2–9 per locule; style glabrous, usually geniculate; stigma entire, discoid to capitate. Fruits indehiscent, dry. Locules usually 1(2)-seeded. Endosperm abundant, strongly ruminate in some species.

The author is indebted to H. Straka, Kiel, who gave valuable comments on pollen morphology and kindly provided an unpublished draft on the family.