Zemitrella contigua

Zemitrella contigua Temporal range: Late Pleistocene PreꞒ Ꞓ O S D C P T J K Pg N ↓
Holotype from Auckland War Memorial Museum
Scientific classification
Kingdom:	Animalia
Phylum:	Mollusca
Class:	Gastropoda
Subclass:	Caenogastropoda
Order:	Neogastropoda
Family:	Columbellidae
Genus:	Zemitrella
Species:	†Z. contigua
Binomial name
†Zemitrella contigua A. W. B. Powell, 1934

Zemitrella contigua is an extinct species of sea snail, a marine gastropod mollusc, in the family Columbellidae, the dove snails. ^[1] Fossils of the species date to the Late Pleistocene, and occur in the strata of Te Piki in the eastern Bay of Plenty, New Zealand.

Description

Reverse view of holotype

In the original description, Powell described the species as follows:

Shell moderately large for the genus, smooth and polished except for about eight evenly spaced weak spirals upon the neck of the base, and another eight much more closely spaced and less prominent upon the fasciole. Spire about equal to height of aperture, outlines only slightly convex. Whorls 5½, plus smooth papillate protoconch of 1½ whorls. Suture linear, false margined below, by the base of the upper-whorl showing through. Body-whorl evenly rounded, but not bulging. Aperture long and narrow, sides parallel medially. Outer-lip vertical above, rounded and contracted basally; without a distinct canal, but there is a shallow anterior sinus. Within the outer-lip there are about ten weak denticles. Columella straight and vertical medially, and with a distinct oblique plait at the base. ^[2]

The holotype of the species measures 7 mm (0.28 in) in height and 2.95 mm (0.116 in) in diameter. ^[2] The species has a slightly larger and less massive shell compared to Zemitrella choava , as well as a thin outer lip and a relatively longer and narrow aperture. The neck of base of the shell is more deeply contracted than in Z. choava. ^[2]

Taxonomy

The species was first described by A.W.B. Powell in 1934. ^[2] The holotype was collected by Powell in August 1933 from 6 km (3.7 mi) east of Cape Runaway in the Bay of Plenty Region, and is held by the Auckland War Memorial Museum. ^{[3] [4]}

Distribution

This extinct marine species dates to the Late Pleistocene (Haweran), and is only known to occur in the strata of the Waipaoa Formation (Te Piki Member), in the eastern Bay of Plenty, New Zealand. ^[3]

References

1. Zemitrella contigua A. W. B. Powell, 1934 . 24 November 2025. Retrieved through: World Register of Marine Species .
2. Powell, A. W. B. (1934). "Upper Pliocene Fossils from Cape Runaway". Records of the Auckland Institute and Museum . 1: 261–274. ISSN   0067-0464. JSTOR   42905956. Wikidata   Q58676565.
3. Blom, Wilma M. (2025). "Annotated Catalogue of Fossil and Extant Molluscan Types in the Auckland War Memorial Museum". Bulletin of the Auckland Museum . 22. doi:10.32912/BULLETIN/22. ISSN   1176-3213. OCLC   1550165130. Wikidata   Q135397912.
4. "Zemitrella contigua". Collections Online. Auckland War Memorial Museum . Retrieved 24 November 2025.

Further reading

• Maxwell, P. A. (2009). Cenozoic Mollusca. pp 232–254 in Gordon, D. P. (ed.) New Zealand inventory of biodiversity. Volume one. Kingdom Animalia: Radiata, Lophotrochozoa, Deuterostomia. Canterbury University Press, Christchurch.