''Voragonema'' is a genus of

hydrozoans Hydrozoa (hydrozoans; from Ancient Greek ('; "water") and ('; "animals")) is a taxonomic class of individually very small, predatory animals, some solitary and some colonial, most of which inhabit saline water. The colonies of the colonial spe ...

belonging to the family

Rhopalonematidae Rhopalonematidae is a family of hydrozoans Hydrozoa (hydrozoans; from Ancient Greek ('; "water") and ('; "animals")) is a taxonomic class of individually very small, predatory animals, some solitary and some colonial, most of which inhabit ...

. The genus comprises four species.Lindsay, Dhugal & Francesc Pagès, 2010. "''Voragonema tatsunoko'' (Trachymedusae: Rhopalonematidae) a new species of benthopelagic medusa, host to the hyperiid amphipod ''Mimonectes spandli'' (Physosomata: Mimonectidae)." ''Zootaxa'' 2671: 31-39. Unlike most

hydromedusae Hydrozoa (hydrozoans; from Ancient Greek ('; "water") and ('; "animals")) is a taxonomic class of individually very small, predatory animals, some solitary and some colonial, most of which inhabit saline water. The colonies of the colonial spec ...

, these do not have a

sessile Sessility, or sessile, may refer to: * Sessility (motility), organisms which are not able to move about * Sessility (botany), flowers or leaves that grow directly from the stem or peduncle of a plant * Sessility (medicine), tumors and polyps that ...

stage. Rather, they spend their entire lives in the water column as plankton. Centripetal expansions protruding from the ring canal is a characteristic that separates this genus from other genera in the family Rhopalonematidae.

Species

*'' Voragonema laciniata'' *'' Voragonema pedunculata'' *'' Voragonema profundicola'' *'' Voragonema tatsunoko''

References

World Register of Marine Species
Rhopalonematidae Hydrozoan genera {{hydrozoa-stub