Blue velvet headshield slug
Chelidonura varians
- Usual depth2–19 m
- Water temperature24–30 °C
- Best monthsApril, November, and December
- How commonRare
Photo credit: (c) Steve Childs, some rights reserved (CC BY) · CC BY · iNaturalist
About this species
Chelidonura varians commonly known as the blue velvet headshield slug or blue velvet nudibranch, is a species of small sea slug, a marine opisthobranch gastropod mollusc in the order Cephalaspidea, the headshield slugs.
Text from the Wikipedia article “Chelidonura varians”, 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: 40 records
- February: 44 records
- March: 44 records
- April: 64 records
- May: 54 records
- June: 30 records
- July: 30 records
- August: 35 records
- September: 45 records
- October: 51 records
- November: 61 records
- December: 65 records
Depth and water temperature
Depth
Mostly recorded at 2–19 m · Deepest record: 50 m
Water temperature
Recorded in surface water of 24–30 °C
Photos
(c) Glen MacLarty, some rights reserved (CC BY) · CC BY · iNaturalist 
(c) Ewout Knoester, some rights reserved (CC BY-SA) · CC BY-SA · iNaturalist 
(c) Ben Costamagna, some rights reserved (CC BY) · CC BY · iNaturalist 
(c) Ben Costamagna, some rights reserved (CC BY) · CC BY · iNaturalist 
no rights reserved · CC0 1.0 · iNaturalist 
(c) Dan Schofield, some rights reserved (CC BY) · CC BY · iNaturalist
Names and classification
- English
- Blue velvet headshield slug, blue velvet headshield slug
Names in 4 more languages
- German
- Veränderliche Kopfschildschnecke
- French
- Chélidonure variable
- Japanese
- ゲンノウツバメガイ
- Simplified Chinese
- 多變燕尾似海牛（多變燕尾擬海牛）
Other scientific names: Chelidonura velutina
Similar species
Lovely Headshield SlugChelidonura amoena
T-bar SwallowtailChelidonura hirundinina
Blue-ringed SwallowtailChelidonura livida
Beautiful SwallowtailPhilinopsis speciosa
- Headlight Swallowtail
Mariaglaja inornata
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).
- 209 open-data records from 1986 to 2026.
- Species data updated October 26, 2026.
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