32 Pāua are ancient rocky shore icons
Mollusca, Gastropoda: Haliotis sp.
Pāua are iconic inhabitants of rocky shores around Aotearoa New Zealand. Known formally as Haliotis, there are three species of pāua living in New Zealand today. And although they have a global fossil record dating back to the Cretaceous, Haliotis is an uncommon discovery in the New Zealand fossil record. Importantly though, the small number of Haliotis fossils that have been found locally reveal that pāua has a long history in Zealandia.
External and internal views of a tiny fossil pāua shell from Cosy Dell. Note the row of tiny pores (tremata) and the iridescent colour still preserved after 25 million years. This fragile shell floated out from its protective ‘cave’ inside a larger gastropod when the shell was washed in water. Image credit: Yutong Wu. |
The Cosy Dell fossil locality in Southland preserves a rare rocky shore environment from between 25.4 and 24.4 million years ago. Several incomplete specimens of Haliotis have been discovered at Cosy Dell but the one shown here is a perfectly-preserved fragile juvenile, just 3 mm long, which displays the row of tiny pores (tremata) characteristic of pāua and retains traces of iridescent pearly nacre.
Pāua cling to a rock substrate with a strong muscular foot and graze on seaweed. The fossils at Cosy Dell occur with a wide range of intertidal and subtidal animals such as barnacles and algal grazers such as chitons. The pāua and chiton fossils therefore provide indirect evidence for a diverse seaweed flora. This is amazing, as soft and fragile seaweeds are rarely, if ever, preserved in the fossil record.
—Written by Daphne E Lee
| Specimen number: OU 44922 | Age: 25.4 to 24.4 million years ago (late Oligocene, boundary between the Duntroonian and Waitakian stages) |
| Locality: Waimumu, Southland | Rock Formation: Chatton Formation |
| Collected by: DE Lee | |
| Citation: Lee D, Lindqvist J, Beu A, Robinson J, Ayress M, Morgans H, Stein J. 2014. Geological setting and diverse fauna of a Late Oligocene rocky shore ecosystem, Cosy Dell, Southland. New Zealand Journal of Geology and Geophysics 57:195–208. doi.org/10.1080/00288306.2014.898666 | |
A collection of fossils that document the history of life. Reference might be made to the history of life in a particular place ('the fossil record of New Zealand'), or the history of a particular group of organisms ('the fossil record of penguins'), or simply the global history of all life ('the fossil record').
145 to 66 million years ago.
Evidence of life from a past geological age. Remains like bones, shells or wood, or an impression like a footprint, or some other evidence of life, from something that was alive more than 11,700 years ago.
The mostly submerged continent of which New Zealand and New Caledonia are a part.
A marine ecosystem that's found in the intertidal zone, where the ocean meets the land.
Iridescent material constructed from calcium carbonate and organic material.
A muscular organ that is part of the body plan of all molluscs. Used in different species for locomotion, grasping or digging.
