''Arctapodema'' is a genus of deep-sea

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 ...

in 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 ...

Description

All ''Arctapodema'' species are characterized by a small hemispherical bell of up to 23 mm in diameter. Furthermore, they are characterized by four simple lips, no gastric peduncle, eight narrow radial canals with gonads on them that are adjacent to the manubrium, numerous alike tentacles in a single row, and free club-shaped marginal statocysts.

Species

* ''Arctapodema ampla'' Vanhöffen, 1902 * ''Arctapodema antarctica'' Vanhöffen, 1912 * ''Arctapodema australis'' Vanhöffen, 1902 * ''Arctapodema macrogaster'' Vanhöffen, 1902 Besides the four accepted species of ''Arctapodema'' reported within the Southern Ocean, one more has been discussed. ''Arctapodema tetragonia'' (Vanhöffen, 1912) is an unaccepted species debated to be ''A. ampla'' due to its comparable morphology: a short stomach and four short lips, but four kidney-shaped gonads on the walls of stomach that are adjacent to the subumbrella, and about 112 tentacles.

Invalid species

* ''Arctapodema antarcticum'' (Vanhöffen, 1912) ncorrect gender suffix* ''Arctapodema australe'' Vanhöffen, 1912 ncorrect spelling

References

Rhopalonematidae Hydrozoan genera Taxa described in 1907 {{hydrozoa-stub