Powellisetia bilirata

Powellisetia bilirata is a species of marine gastropod mollusc in the family Rissoidae. First described by Winston Ponder in 1965, it is endemic to the waters of New Zealand.

Description

In the original description, Ponder described Powellisetia bilirata as follows:
P. bilirata has two stronger spirals on its shell, that cross over the whorls at an angle. The species measures, by.

Taxonomy

P. bilirata was first described by Winston Ponder in 1965. The holotype is held by the Auckland War Memorial Museum.

Distribution

The species is endemic to New Zealand. The holotype was collected by Ken Hipkins on 9 April 1955 from shell sand at McGregors Bay, Whangārei Heads, Northland Region. It is found in to the north-east of the North Island, as far north as Manawatāwhi / Three Kings Islands, and has been found neat the volcanic Whakaari / White Island.