Mauidrillia inaequalis

Mauidrillia inaequalis is an extinct species of sea snail, a marine gastropod mollusc in the family Horaiclavidae.[1] Fossils of the species date to the late Oligocene and early Miocene, and are found in South Canterbury and Otago, New Zealand.

Mauidrillia inaequalis
Temporal range: late Oligocene–early Miocene
Holotype from Auckland War Memorial Museum
Scientific classification Edit this classification
Kingdom: Animalia
Phylum: Mollusca
Class: Gastropoda
Subclass: Caenogastropoda
Order: Neogastropoda
Family: Horaiclavidae
Genus: Mauidrillia
Species:
M. inaequalis
Binomial name
Mauidrillia inaequalis

Description

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Reverse view of holotype

The species has a moderately sized shell, with 7.5 whorls and a protoconch of 1.5 inflated whorls. The whorls are strongly angulate just above the middle, and the shells are deeply concave at the shoulder. The shells have broad axials and are crossed by fine, close spaced spirals. The holotype of the species measures 10 mm (0.39 in) in height and 4 mm (0.16 in) in diameter.[2]

Taxonomy

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The species was first described by A.W.B. Powell in 1942.[2] The holotype was collected from Otiake, Waitaki Valley, Otago at an unknown date prior to 1943, and is held by the Auckland War Memorial Museum.[3][4]

Distribution

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This extinct marine species occurs in late Oligocene and early Miocene strata of Blue Cliffs and the Pareora River of South Canterbury, and the Waitaki Valley of Otago, New Zealand.[3][2][5]

References

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Further reading

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  • Maxwell, P.A.. 1988. Late Miocene Deep-Water Mollusca from the Stillwater Mudstone at Greymouth, Westland, New Zealand: Paleoecology and Systematics. New Zealand Geological Survey Paleontological Bulletin 55
  • 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