Syntomodrillia circinata

Syntomodrillia circinata Temporal range: late Oligocene–early 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:	Drilliidae
Genus:	Syntomodrillia
Species:	†S. circinata
Binomial name
†Syntomodrillia circinata Powell, 1944

Syntomodrillia circinata is an extinct species of sea snail, a marine gastropod mollusc in the family Drilliidae. ^[1] Fossils of the species have been found in strata of the Port Phillip Basin of Victoria, and date to either the late Oligocene or the early Miocene.

Description

Reverse view of holotype

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

Species very similar to obsoleta , but much larger, axials more erect, and connected across the shoulder-angle by a weak thread; five moderately strong spirals on the neck. Axials 11 per whorl. ^[2]

The holotype of the species measures 6 mm (0.24 in) in height and 2.5 mm (0.098 in) in diameter. ^[2]

Taxonomy

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

Distribution

This extinct marine species dates to either the late Oligocene or the early Miocene, and occurs in the strata of the Port Phillip Basin of Victoria, Australia, either the Jan Juc Formation or the Puebla Formation. ^{[3] [5]}

References

1. Syntomodrillia circinata A. W. B. Powell, 1944 † . 13 November 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. Wikidata   Q135397912.
4. "Syntomodrillia circinata". Collections Online. Auckland War Memorial Museum . Retrieved 13 November 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.