Description from Flora of China
Andrachne [unranked] Arachne Endlicher; Arachne (Endlicher) Pojarkova; Archileptopus P. T. Li; Thelypetalum Gagnepain.
Herbs to shrubs, monoecious; indumentum of simple hairs, sometimes absent. Leaves alternate, petiolate; stipules small, usually membranous, glabrous or ciliate, persistent; leaf blade simple, membranous to leathery, margin entire, venation pinnate. Inflorescences axillary, 1-flowered or fascicled, male flowers sometimes on short densely bracteate inflorescences. Male flowers: pedicels usually filiform; sepals 5(or 6), free or connate at base, imbricate; petals 5(or 6), usually shorter than sepals, mostly membranous; disk with 5(or 6) contiguous regular segments bilobed for 1/3-4/5 of their length; stamens 5(or 6), opposite sepals; filaments free; anthers introrse or extrorse, longitudinally dehiscent; pistillode composed of 3 free segments or 3-lobed. Female flowers: pedicels apically dilated; sepals larger than male; petals membranous, minute and often hidden under disk lobes; disk annular, regularly divided into 5(or 6) emarginate segments; ovary 3-6-locular; ovules 2 per locule; styles 3-6, apex bifid to base or nearly so, recurved; stigmas apically dilated to capitate. Fruit a capsule, dehiscent into 3(-6) 2-valved cocci when mature, smooth, sometimes with faint reticulate venation. Seeds without caruncle, rounded triquetrous to almost reniform, smooth, rugose or pitted, dull; endosperm fleshy; embryo curved; cotyledons flattened and broad.
Some authors treated Leptopus as part of a more widely circumscribed Andrachne Linnaeus, but that view is not accepted here (see Vorontsova et al., Amer. J. Bot. 94: 2026-2040. 2007; Vorontsova & Petra Hoffmann, Kew Bull., in press).
Andrachne cavaleriei H. Léveillé (Repert. Spec. Nov. Regni Veg. 12: 187. 1913) is the basionym of Lysimachia capillipes Hemsley var. cavaleriei (H. Léveillé) Handel-Mazzetti in the Primulaceae (see Fl. China 15: 52. 1996). Andrachne millietii H. Léveillé (Bull. Géogr. Bot. 24: 146. 1914) is the basionym of Lysimachia millietii (H. Léveillé) Handel-Mazzetti in the Primulaceae (see Fl. China 15: 50. 1996).
"Arachne Necker" (Elem. Bot. 2: 348. 1790) was not validly published because the work in which it appeared is among the Opera Utique Opressa.
Nine species: China, India, Indonesia, Malaysia, Myanmar, Pakistan, Philippines, Thailand, Vietnam; SW Asia (Caucasus, Iran); six species (three endemic) in China.
(Authors: Li Bingtao (李秉滔 Li Ping-tao); Maria Vorontsova)