Butterfly Split-nose Sap-sucker
Cyerce nigricans
- Usual depth1–16 m
- Water temperature24–29 °C
- Best monthsJanuary, February, and March
- How commonRare
Photo credit: (c) Ewout Knoester, some rights reserved (CC BY-SA) · CC BY-SA · iNaturalist
About this species
Cyerce nigricans, is a species of sacoglossan sea slug, a shell-less marine opisthobranch gastropod mollusk in the family Caliphyllidae. Akin to other species of sea slugs, they dwell in reef flats and similar areas. In contrast to the rest of the genus Cyerce, Cyerce nigricans are not cryptically colored. They are often used as the staple animal of the Great Barrier Reef because of their outlandish coloration, often appearing in blacks, yellows, reds, and oranges. The cerata of Cyerce nigricans are occasionally compared to the wings of a butterfly, based on their shape and color. This sea slug has developed autotomy, or the ability to drop parts of its cerata when threatened.
Text from the Wikipedia article “Cyerce nigricans”, 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: 21 records
- February: 17 records
- March: 23 records
- April: 15 records
- May: 7 records
- June: 8 records
- July: 10 records
- August: 8 records
- September: 13 records
- October: 15 records
- November: 12 records
- December: 16 records
Depth and water temperature
Depth
Mostly recorded at 1–16 m · Deepest record: 18.3 m
Water temperature
Recorded in surface water of 24–29 °C
Photos
(c) Ewout Knoester, some rights reserved (CC BY-SA) · CC BY-SA · iNaturalist 
no rights reserved · CC0 1.0 · iNaturalist 
no rights reserved · CC0 1.0 · iNaturalist 
(c) Henrik Kibak, some rights reserved (CC BY) · CC BY · iNaturalist
Names and classification
- English
- Butterfly Split-nose Sap-sucker, Black-and-gold Sapsucking Slug, Leaf-gilled Slug
Names in 3 more languages
- French
- Cyerce noirâtre
- Japanese
- キマダラウロコウミウシ
- Simplified Chinese
- 黑美葉海蛞蝓
Other scientific names: Lobifera nigricans
Similar species
Multi-spotted Split-nose Sap-suckerCyerce bourbonica
Tiger Butterfly Sea SlugCyerce nigra
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).
- 93 open-data records from 1948 to 2025.
- Species data updated November 1, 2026.
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