Biology:Powellisetia unicarinata

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Short description: Species of gastropod


Powellisetia unicarinata
Powellisetia unicarinata (Powell, 1930) (AM MA70544).jpg
Holotype of Powellisetia unicarinata from Auckland War Memorial Museum
Scientific classification edit
Domain: Eukaryota
Kingdom: Animalia
Phylum: Mollusca
Class: Gastropoda
Subclass: Caenogastropoda
Order: Littorinimorpha
Family: Rissoidae
Genus: Powellisetia
Species:
P. unicarinata
Binomial name
Powellisetia unicarinata
(Powell, 1930)
Synonyms[1]
  • Notosetia unicarinata Powell, 1930

Powellisetia unicarinata is a species of marine gastropod mollusc in the family Rissoidae.[1] First described by Powell in 1930 as Notosetia unicarinata, it is endemic to the waters of New Zealand.

Taxonomy

Originally described as Notosetia unicarinata in 1930 by Powell,[2] the species name was revised as Powellisetia unicarinata in 1965 by Winston Ponder.[3]

Description

Powellisetia bilirata has a minute, roughly ovate shell with a single strong spiral ridge. It is coloured dull-white.[2] The species measures 1.19mm, by 0.59mm.[4] The species' shell has a reasonably tall spire and a strongly tilted protoconch, and shell width is the major factor that varies between individuals in the species.[3]

The species is similar in appearance to Powellisetia porcellanoides, but can be distinguished by its angled carnate shoulder.[3]

Distribution

The species is endemic to New Zealand.[1] The holotype dredged by Powell in 1924, from a depth of 9–11 metres at Tryphena Bay on Great Barrier Island..[5] It is found in the north-east of the North Island,[4] as far north as Manawatāwhi / Three Kings Islands,[6]

References

Wikidata ☰ Q6777011 entry