
Diloma coracinum
- Usual depth0 m
- Water temperature12–18 °C
- Best monthsApril, May, and June
- How commonRare
Photo credit: (c) Javier, some rights reserved (CC BY), uploaded by Javier · CC BY · iNaturalist
About this species
Diloma coracinum is a species of small sea snail, a marine gastropod mollusc in the family Trochidae, the top snails. The Māori name is māihi.
Text from the Wikipedia article “Diloma coracinum”, licensed CC BY-SA 4.0. Read the article
Where and when
Where it has been recorded
Worldwide
Loading the map
Best months
Worldwide (open data)
- January: 5 records
- February: 7 records
- March: 7 records
- April: 10 records
- May: 11 records
- June: 10 records
- July: 7 records
- August: 3 records
- September: 2 records
- October: 2 records
- November: 1 records
- December: 7 records
Depth and water temperature
Depth
Mostly recorded at 0 m · Deepest record: 0 m
Water temperature
Recorded in surface water of 12–18 °C
Photos

(c) Javier, some rights reserved (CC BY), uploaded by Javier · CC BY · iNaturalist 
(c) Saryu Mae 前 朝琉, some rights reserved (CC BY), uploaded by Saryu Mae 前 朝琉 · CC BY · iNaturalist 
(c) Javier, some rights reserved (CC BY), uploaded by Javier · CC BY · iNaturalist 
(c) Javier, some rights reserved (CC BY) · CC BY · iNaturalist 
(c) Saryu Mae 前 朝琉, some rights reserved (CC BY) · CC BY · iNaturalist 
(c) Saryu Mae 前 朝琉, some rights reserved (CC BY) · CC BY · iNaturalist 
(c) Kelvin Perrie, some rights reserved (CC BY) · CC BY · iNaturalist
Names and classification
Other scientific names: Trochocochlea excavata, Trochus coracinus
Similar species
Scorched monodontDiloma aethiops
Speckled PeriwinkleDiloma concameratum
Mudflat Top ShellDiloma subrostratum

Knobbed Top SnailDiloma bicanaliculatum
- Bluish Top Shell
Diloma nigerrimum
Sources and credits
Names and taxonomy: WoRMS (CC BY 4.0) and the GBIF Backbone (CC BY 4.0). Photos: iNaturalist observers, each under the licence shown (CC0, CC BY or CC BY-SA).
- Depth, temperature, months and maps: records from OBIS and GBIF under CC0 or CC BY.
- Descriptions: Wikipedia, licensed CC BY-SA, each linked to its article.
- Conservation status as published by GBIF (IUCN Red List).
- 181 open-data records from 1921 to 2001.
- Species data updated November 2, 2026.
Log what you see on your next dive
The free DiveHive diver app keeps your logbook with every sighting and shows what lives at the site you dive next.