Amphinema Haeckel, 1879

Diagnosis. Colonies stolonal, hydrorhiza creeping, hydrocaulus well developed, unbranched, covered by perisarc, longer than extended hydranth; hydranths spindle-shaped with one whorl of amphicoronate filiform oral tentacles, with conical hypostome. Gonophores arising either on stolon or caulus or both, releasing free medusae. Medusa generally with a large apical projection, with two opposite tentacles, without gastric peduncle, with marginal warts, manubrium with broad base and four simple lips, gonads on manubrium in adradial or interradial position, ocelli and marginal cirri may be present.