Humpback Brotula
Grammonus robustus
- Usual depth298–352 m
- Water temperature25–29 °C
- Best monthsJanuary and November
- How commonRare
Where and when
Where it has been recorded
Worldwide
Loading the map
Best months
Worldwide (open data)
- January: 3 records
- February: 1 records
- March: 1 records
- April: 1 records
- May: 0 records
- June: 0 records
- July: 0 records
- August: 0 records
- September: 0 records
- October: 0 records
- November: 4 records
- December: 0 records
Depth and water temperature
Depth
Mostly recorded at 298–352 m · Deepest record: 352 m
Water temperature
Recorded in surface water of 25–29 °C
Names and classification
- English
- Humpback Brotula, Humpback Cusk
Names in 1 more languages
- Japanese
- Sedakaitachiuo, Semushi-itachiuo, セダカイタチウオ
Other scientific names: Oligopus robustus
Similar species
Grey BrotulaBidenichthys consobrinus
- Gelatinous Blindfish
Aphyonus gelatinosus
- Spotted Gelatinous Cusk
Barathronus maculatus
- Slimy Cusk
Brosmophyciops pautzkei
- White Brotula
Cataetyx chthamalorhynchus
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.
- Conservation status as published by GBIF (IUCN Red List).
- 35 open-data records from 1909 to 2025.
- Species data updated November 3, 2026.
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