Mauidrillia intumescens

Mauidrillia intumescens Temporal range: late Miocene 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:	Horaiclavidae
Genus:	Mauidrillia
Species:	†M. intumescens
Binomial name
†Mauidrillia intumescens A. W. B. Powell, 1944

Mauidrillia intumescens is an extinct species of sea snail, a marine gastropod mollusc in the family Horaiclavidae. ^[1] Fossils of the species date to the late Miocene, and have been found in strata of the Gippsland Basin of Victoria, Australia.

Description

Reverse view of holotype

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

Shell large for genus; distinguished from all other Australian members by the broad, heavy peripheral fold. A moderately broad subsutural fold, on the early spire-whorls only. Surface of spire crowded with spiral threads, 3 on subsutural fold, 4-8 on broadly concave shoulder, 5-6 on peripheral fold, and 1 or 2 stronger cords below it. Six primary cords on base, plus intermediate threads and 8 closely spaced threads on the anterior end. Axials strongly nodulose on the peripheral fold, 14 per whorl; weakly nodulose on the subsutural fold, but elsewhere they are narrow and weak. ^[2]

The holotype of the species measures 18 mm (0.71 in) in height and 7.5 mm (0.30 in) in diameter. ^[2]

Taxonomy

The species was first described by A.W.B. Powell in 1944. ^[2] The holotype was collected from the Jemmys Point Formation in the Gippsland Lakes, Victoria at an unknown date prior to 1937, and is held by the Auckland War Memorial Museum. ^{[3] [4]}

Distribution

This extinct marine species occurs in late Miocene strata of the Gippsland Basin of Victoria, including the Jemmys Point Formation. ^{[3] [5]}

References

1. Mauidrillia intumescens A. W. B. Powell, 1944 † . 4 December 2025. Retrieved through: World Register of Marine Species .
2. Powell, A. W. B. (1944). "The Australian Tertiary Mollusca of the Family Turridae". Records of the Auckland Institute and Museum . 3: 3–68. ISSN   0067-0464. JSTOR   42905993. Wikidata   Q58676624.
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. "Mauidrillia intumescens". Collections Online. Auckland War Memorial Museum . Retrieved 4 December 2025.
5. Darragh, Thomas A. (August 2024). "A checklist of Australian marine Cenozoic Mollusca". Memoirs of Museum Victoria . 83: 37–206. doi:10.24199/J.MMV.2024.83.02. ISSN   1447-2546. Wikidata   Q136396722.