Description from Flora of China
Antigona Vellozo; Athenaea Schreber (1789), not Adanson (1763); Vareca Gaertner.
Shrubs or small trees. Leaves alternate, usually petiolate; stipules usually small, caducous, rarely larger and/or persistent; leaf blade usually pinnate-veined, sometimes 3-veined from base, often with pellucid glandular dots and lines throughout (view at 10 × against light), margin entire or toothed. Flowers perigynous, bisexual, small, usually clustered in axillary, few- to many flowered, sessile or shortly pedunculate fascicles, rarely solitary or in small cymes; bracts papery or scalelike, generally ovate, small, congested at fascicle base to form a persistent cushion; pedicels usually present, articulate, rarely flowers practically sessile. Sepals 4 or 5, imbricate, joined in basal part to form a shallow or deeper cup, free above, cup never adnate to ovary. Petals absent. Disk cuplike, adnate to inside of calyx tube, free from ovary, rim lobed; lobes triangular, oblong, or clavate, usually hairy, either in same row as and alternating with stamens, or in an intrastaminal row. Stamens (6-)8-10(-12); filaments inserted on rim of disk cup. Ovary superior, 1-loculed; placentas 2-4, each with several ovules; style 1, entire or distally 3-branched, sometimes very short; stigma capitate, 3-lobed when style is entire. Capsule fleshy to leathery, globose, ellipsoid or 3-angled when fresh, mostly 6-ribbed when dry, (2 or)3(or 4)-valvate, dehisced valves often naviculate; sepals, stamen filaments, disk, and disk lobes generally persistent at capsule base, style remnant often persistent at apex. Seeds several, ovoid or obovoid, arillate, aril completely covering seed, membranous or fleshy, often brightly colored, soft, partly fimbriate.
In Chinese species: flowers in axillary glomerules; disk lobes in same row as stamens; style entire; capsule fleshy.
More gatherings are needed for the genus from China, Myanmar, India, Laos, Thailand, and Vietnam, from which more accurate, detailed, and standardized descriptions and keys can be drawn. Chinese material of Casearia kurzii, C. tardieuae, and C. velutina seems particularly scarce. Between some species, the flowers and fruit offer few diagnostic characters. The following key is tentative.
About 180 species: tropical and subtropical regions of Africa, Asia, Australia, North and South America, and the Pacific islands; seven species in China.