Mauidrillia aldingensis

Mauidrillia aldingensis Temporal range: late Eocene 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. aldingensis
Binomial name
†Mauidrillia aldingensis A. W. B. Powell, 1944

Mauidrillia aldingensis is an extinct species of sea snail, a marine gastropod mollusc in the family Horaiclavidae. ^[1] Fossils of the species date to the late Eocene, and have been found in strata of the St Vincent Basin of South Australia, and the Otway Basin of South Australia and Victoria.

Description

Reverse view of holotype

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

A robust, strongly sculptured species with the axials developed into vertically compressed tubercles where crossed by the carina. Suture bordered below by a narrow, sharp cord, three spiral threads on the shoulder, followed by the peripheral carina and two equally strong cords below it. On the body-whorl the development of intermediates increases the spirals to seven from the carina to the lower suture; there are about 29 spirals from the carina to the anterior end. Axials 13 per whorl, plus numerous fine axial threads which obliquely fenestrate the shoulder spirals. ^[2]

The holotype of the species measures 9.5 mm (0.37 in) in height and 3.8 mm (0.15 in) in diameter. ^[2] The species has a protoconch of between 1.3-2.0 whorls (typically 1.5). ^[3]

Taxonomy

The species was first described by A.W.B. Powell in 1944. ^[2] The holotype was collected from the Blanche Point Formation in Aldinga, South Australia at an unknown date prior to 1945, and is held by the Auckland War Memorial Museum. ^{[4] [5]}

D. C. Long theorised that M. aldingensis was an ancestral species of the Oligocene-Miocene species M. torquayensis , M. pullulascens , M. trispiralis , M. consutilis , M. partinoda and M. serrulata . ^[3]

Ecology

M. aldingensis was an epifaunal carnivore. ^[6]

Distribution

This extinct marine species occurs in late Eocene strata of the St Vincent Basin and Otway Basin, including the Blanche Point Formation and Browns Creek Formation of South Australia and Victoria. ^{[4] [7]} A fossil found in the Southern Carnarvon Basin of Western Australia dating to the Middle-Late Eocene may represent an occurrence of M. aldingensis, however this fossil differed morphologically by having more tumid whorls and a more elongated canal. ^[8]

References

1. Mauidrillia aldingensis 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. Long, D. C. (1981). "Late Eocene and Early Oligocene Turridae (Gastropoda: Prosobranchiata) of the Brown's Creek and Glen Aire Clays, Victoria, Australia" (PDF). Memoirs of the National Museum of Victoria. 42 (1): 15–55. doi:10.24199/J.MMV.1981.42.03. ISSN   0083-5986. Wikidata   Q56195002.
4. 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.
5. "Mauidrillia aldingensis". Collections Online. Auckland War Memorial Museum . Retrieved 4 December 2025.
6. "†Mauidrillia aldingensis Powell 1944 (snail)". Paleobiology Database. Retrieved 4 December 2025.
7. 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.
8. Darragh, Thomas A.; Kendrick, George W. (2008). "Silicified Eocene molluscs from the Lower Murchison district, Southern Carnarvon Basin, Western Australia". Records of the Western Australian Museum. 24: 217–246. doi:10.18195/issn.0312-3162.24(3).2008.217-246.