Blackbelly Triplefin
Enneapterygius hemimelas
- Usual depth1–16 m
- Water temperature22–29 °C
- Best monthsJanuary, April, and November
- How commonRare
About this species
The halfblack triplefin, also known as the half-black triplefin, blackbelly triplefin, or the green-tail threefin, is a species of triplefin blenny in the genus Enneapterygius. It was originally described by R. Kner and F. Steindachner in 1867. It is a non-migratory tropical blenny known from coral reefs in the western Pacific Ocean, and has been described from the Ryukyu Islands to eastern Australia. It has been recorded swimming at a depth range of 0–30 metres.
Text from the Wikipedia article “Halfblack triplefin”, 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: 18 records
- February: 9 records
- March: 0 records
- April: 17 records
- May: 15 records
- June: 6 records
- July: 0 records
- August: 1 records
- September: 16 records
- October: 9 records
- November: 24 records
- December: 8 records
Depth and water temperature
Depth
Mostly recorded at 1–16 m · Deepest record: 75 m
Water temperature
Recorded in surface water of 22–29 °C
Names and classification
- English
- Blackbelly Triplefin, Green-tail Threefin, Halfblack Threefin, Half-black Triplefin, Halfblack Triplefin
Names in 1 more languages
- Japanese
- Akegoromohebigimpo, アケゴロモヘビギンポ
Other scientific names: Enneapterygius fuligicauda, Enneapterygius macrobrachium, Enneapterygius similis, Tripterigium hemimelas, Tripterygion fuligicauda, Tripterygion hemimelas, Tripterygion macrobrachium, Tripterygium hemimelas
Similar species
Highfin ThreefinEnneapterygius tutuilae
- Blacktail Threefin
Enneapterygius bahasa
- Northern Bicoloured Triplefin
Enneapterygius flavoccipitis
- Blackbelly Triplefin
Enneapterygius fuscoventer
- Minute Triplefin
Enneapterygius minutus
- Blacktail Triplefin
Enneapterygius nigricauda
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).
- 290 open-data records from 1902 to 2023.
- Species data updated October 26, 2026.
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