trachylinae

Genus: Crossota

…a genus of rhopalonematid hydrozoans that are widespread throughout all oceans. Unlike some other hydrozoans (and like trachymedusae) members of Crossota do not have a sessile larval stage. Instead they spend their entire lives in the water column as “plankton”. Once they reach adulthood as medusae they will feed on zooplankton which are dispatched via nematocysts.

Classification

Animalia-Cnidaria-Medusozoa-Hydrozoa-Trachylinae-Trachymedusae-Rhopalonemtidae-Crossata

Image: Kevin Raskoff, NOAA Photo Library

Botrynema ellinorae

…is a species of Halicreatid hydrozoan which is typically encountered in the mesopelagic and bathypelagic zones of the Arctic ocean at depths of around (400 to 1,400 m). However it is also been recorded in subarctic regions of the Atlantic Ocean as well. B. ellinorae is poorly researched and as such its diet and ecology is not known, it is thought that B. ellinorae lacks a polyp stage and is holoplanktonic.

Classification

Animalia-Cnidaria-Hydrozoa-Trachylinae-Trachymedusae-Halicreatidae-Botrynema-B. ellinorae

Image: Kevin Raskoff