Isognomon nucleus
- Usual depth1 m
- Water temperature20–30 °C
- Best monthsMarch, July, and September
- How commonRare
Photo credit: (c) Saryu Mae 前 朝琉, some rights reserved (CC BY) · CC BY · iNaturalist
Where and when
Where it has been recorded
Worldwide
Loading the map
Best months
Worldwide (open data)
- January: 2 records
- February: 1 records
- March: 11 records
- April: 4 records
- May: 6 records
- June: 0 records
- July: 8 records
- August: 4 records
- September: 13 records
- October: 2 records
- November: 3 records
- December: 1 records
Depth and water temperature
Depth
Mostly recorded at 1 m · Deepest record: 1 m
Water temperature
Recorded in surface water of 20–30 °C
Names and classification
Names in 1 more languages
- Japanese
- ヘリトリアオリガイ
Other scientific names: Isognomon (Parviperna) nucleus, Isognomon acutirostris, Isognomon dentifer, Isognomon rupella, Melina dentifera, Parviperna francisensis, Parviperna perexigua, Parviperna rupella, Pedalion francisensis, Perna acutirostris, Perna dentifera, Perna lobata, Perna nana, Perna nucleus, Perna pectinata, Perna planorbis, Perna quadrangularis, Perna rupella
Similar species
Round Toothed OysterIsognomon ephippium
Elongate Toothed OysterIsognomon isognomum
Pod tree oysterIsognomon legumen
Brown Purse ShellIsognomon perna
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.
- Conservation status as published by GBIF (IUCN Red List).
- 172 open-data records from 1819 to 2021.
- Species data updated November 3, 2026.
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