Zeatoma

Zeatoma
Temporal range: 39.1–3.70 Ma
Zeatoma anomala
Scientific classification Edit this classification
Kingdom: Animalia
Phylum: Mollusca
Class: Gastropoda
Subclass: Caenogastropoda
Order: Neogastropoda
Family: †Pseudotomidae
Genus: †Zeatoma
P. A. Maxwell, 1992
Type species
† Marshallena impar

Zeatoma is a genus of extinct sea snails, marine gastropod molluscs in the family Pseudotomidae. Species in the genus begin to appear in fossil record in the Kaiatan stage of the Eocene, and are only known to occur in New Zealand, living in warm water environments. Falling temperatures during the Pliocene has been suggested as a reason for the extinction of Zeatoma.

Description

Members of the genus have fine, closely spaced spiral threads that are located between the primary spiral cords, which are not bisected by axial sculpture.

Taxonomy

Zeatoma was first described in 1992 by Phillip A. Maxwell.

Ecology

Members of Zeatoma preferred to live in warm waters. The genus likely became extinct due to falling seawater temperatures during the Pliocene.

Distribution

All known fossil species have been found in New Zealand, and date to between the Kaiatan stage of the Eocene (39.1 million years ago) to the Waipipian stage of the Pliocene (3.70 million years ago).

Species

Species within the genus Zeatoma include:

References

  1. 1 2 Zeatoma P. A. Maxwell, 1992 †. Retrieved through: World Register of Marine Species on 22 January 2026.
  2. ↑ Beu, Alan Glenn (2011). "Marine Mollusca of isotope stages of the last 2 million years in New Zealand. Part 4. Gastropoda (Ptenoglossa, Neogastropoda, Heterobranchia)". Journal of the Royal Society of New Zealand. 41 (1): 1–153. doi:10.1080/03036758.2011.548763. Wikidata Q54553193.
  3. ↑ Maxwell, P.A. (1992). "Eocene Mollusca from the vicinity of McCulloch's Bridge, Waihao River, South Canterbury, New Zealand: paleoecology and systematics". New Zealand Geological Survey Paleontological Bulletin. 65.
  4. ↑ Rust, S.; Gordon, Dennis Preston (2011). "Plio-Pleistocene Bryozoan faunas of the Wanganui Basin, New Zealand: stratigraphic distribution and diversity". New Zealand Journal of Geology and Geophysics. 54 (2): 151–165. doi:10.1080/00288306.2010.514928. Wikidata Q123250864.
  5. ↑ Beu, Alan Glenn; Kitamura, Akihisa (1998). "Exposed coasts vs sheltered bays: contrast between New Zealand and Japan in the molluscan record of temperature change in Plio–Pleistocene cyclothems". Sedimentary Geology. 122 (1–4): 129–149. doi:10.1016/s0037-0738(98)00102-x. Wikidata Q127114061.
  6. ↑ Maxwell, P.A. (2009). "Cenozoic Mollusca". In Gordon, D.P. (ed.). New Zealand Inventory of Biodiversity. Volume one. Kingdom Animalia: Radiata, Lophotrochozoa, Deuterostomia. Christchurch: Canterbury University Press. p. 250. ISBN 978-1-877257-72-8.
  7. ↑ Blom, Wilma Maija (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. OCLC 1550165130. Wikidata Q135397912.