Rhopalonematidae

Rhopalonematidae is a family of hydrozoans. The family comprises 15 genera and 36 species.

Crossota is a genus of hydrozoans of the family Rhopalonematidae. The genus comprises five species. Unlike most hydromedusae, these do not have a sessile stage. Rather, they spend their entire lives in the water column as plankton. The genus Crossota is widespread throughout the oceans.

species of cnidarian

species of cnidarian

species of cnidarian

Aglantha is a genus of deep-sea hydrozoans of the family Rhopalonematidae.

species of cnidarian

species of cnidarian

Voragonema is a genus of hydrozoans belonging to the family Rhopalonematidae. The genus comprises four species. Unlike most hydromedusae, these do not have a sessile 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.

Sminthea is a genus of deep-sea hydrozoans of the family of Rhopalonematidae,

Rhopalonema is a genus of deep-sea hydrozoans of the family Rhopalonematidae.

species of cnidarian

species of cnidarian

Arctapodema is a genus of deep-sea hydrozoans in the family Rhopalonematidae.

Amphogona is a genus of deep-sea hydrozoans of the family of Rhopalonematidae. It has a cosmopolitan distribution in tropical to temperate oceans.

Colobonema is a genus of deep-sea hydrozoans.

Pantachogon is a genus of hydrozoans of the family Rhopalonematidae. The genus includes three species.

Benthocodon is a genus of hydrozoans of the family Rhopalonematidae. The genus contains two known species: Benthocodon hyalinus and Benthocodon pedunculatus, however due to the small size and red pigmentation, they can easily be confused with related genera. Unlike many hydromedusae, these jellyfish do not have a sessile stage. Rather, they spend their entire lives in the water column as plankton. The genus Benthocodon can be found near the sea floor in the Pacific Ocean from Antarctica to California to the Arctic Ocean.

species of cnidarian

Vampyrocrossota is a genus of hydrozoans of the family Rhopalonematidae. The genus only contains one species, Vampyrocrossota childressi. Unlike many hydromedusae, these animals do not have a sessile stage. Rather, they spend their entire lives in the water column as plankton. It is the only known species with a medusa that is truly black.

species of cnidarian