Variable Swallowtail
Mariaglaja tsurugensis
- Usual depth2–15 m
- Water temperature20–29 °C
- Best monthsMarch, April, and October
- How commonRare
Photo credit: (c) Emanuele Santarelli, some rights reserved (CC BY-SA) · CC BY-SA · iNaturalist
About this species
Mariaglaja tsurugensis is a species of sea slug, or "headshield slug", a marine opisthobranch gastropod mollusk in the family Aglajidae. This species lives from Tanzania to Australia.
Text from the Wikipedia article “Mariaglaja tsurugensis”, 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: 26 records
- February: 26 records
- March: 28 records
- April: 45 records
- May: 17 records
- June: 22 records
- July: 19 records
- August: 24 records
- September: 27 records
- October: 34 records
- November: 21 records
- December: 18 records
Depth and water temperature
Depth
Mostly recorded at 2–15 m · Deepest record: 20.5 m
Water temperature
Recorded in surface water of 20–29 °C
Photos
(c) Pierre Pericard, some rights reserved (CC BY) · CC BY · iNaturalist 
(c) libby hepburn, some rights reserved (CC BY) · CC BY · iNaturalist 
(c) Georgina Jones, some rights reserved (CC BY-SA) · CC BY-SA · iNaturalist 
(c) libby hepburn, some rights reserved (CC BY) · CC BY · iNaturalist 
(c) Julien Renoult, some rights reserved (CC BY) · CC BY · iNaturalist 
(c) Dan Schofield, some rights reserved (CC BY) · CC BY · iNaturalist
Names and classification
- English
- Variable Swallowtail
Names in 2 more languages
- Japanese
- ミョウジンツバメガイ
- Simplified Chinese
- 敦賀美尾海蛞蝓
Other scientific names: Chelidonura babai, Chelidonura sandrana, Chelidonura tsurugensis, Mariaglaja sandrana
Similar species
- Headlight Swallowtail
Mariaglaja inornata
Lovely Headshield SlugChelidonura amoena
T-bar SwallowtailChelidonura hirundinina
Beautiful SwallowtailPhilinopsis speciosa
Speckled Swallow-tailed Sea SlugBiuve fulvipunctata
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).
- 184 open-data records from 1973 to 2026.
- Species data updated October 26, 2026.
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