Blackgill Tenellia
Phestilla melanobrachia
- Usual depth5–20 m
- Water temperature18–30 °C
- Best monthsApril, May, and August
- How commonRare
Photo credit: (c) Dan Schofield, some rights reserved (CC BY), uploaded by Dan Schofield · CC BY · iNaturalist
About this species
Phestilla melanobrachia is a species of sea slug, an aeolid nudibranch, a marine gastropod mollusk in the family Trinchesiidae.
Text from the Wikipedia article “Phestilla melanobrachia”, 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: 27 records
- February: 48 records
- March: 44 records
- April: 93 records
- May: 85 records
- June: 41 records
- July: 58 records
- August: 70 records
- September: 63 records
- October: 37 records
- November: 31 records
- December: 35 records
Depth and water temperature
Depth
Mostly recorded at 5–20 m · Deepest record: 28 m
Water temperature
Recorded in surface water of 18–30 °C
Photos
(c) Robin White, some rights reserved (CC BY) · CC BY · iNaturalist 
(c) Jakkarin Burananit, some rights reserved (CC BY) · CC BY · iNaturalist 
(c) Dan Schofield, some rights reserved (CC BY) · CC BY · iNaturalist 
(c) Dan Schofield, some rights reserved (CC BY) · CC BY · iNaturalist 
(c) Georgina Jones, some rights reserved (CC BY-SA) · CC BY-SA · iNaturalist 
(c) Georgina Jones, some rights reserved (CC BY-SA) · CC BY-SA · iNaturalist 
(c) Debra Baker, some rights reserved (CC BY) · CC BY · iNaturalist
Names and classification
- English
- Blackgill Tenellia, Cup Coral Nudibranch
Names in 2 more languages
- Japanese
- イボヤギミノウミウシ
- Simplified Chinese
- 黑枝背鰓海蛞蝓, 黑枝背鰓海蛞蝓（黑枝羽螅海蛞蝓）
Other scientific names: Tenellia melanobrachia
Similar species
drab aeolidPhestilla sibogae
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).
- 205 open-data records from 1874 to 2026.
- Species data updated October 26, 2026.
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