Delicate Whiptail
Hymenogadus gracilis
- Usual depth255–540 m
- Water temperature17–28 °C
- Best monthsJuly, September, and November
- How commonRare
Photo credit: (c) W Schwarzhans, some rights reserved (CC BY) · CC BY · iNaturalist
About this species
The graceful grenadier is a species of rattail fish. It is found at depths of 160–345 m (525–1,132 ft) in tropical and subtropical seas worldwide. This is one of the smallest of the rattails, growing to no more than 13 cm (5.1 in) in length. It is a slender fish with a large mouth, with rows of very small teeth, positioned in the underside of the skull. There is a short, thin chin barbel. It is more strikingly marked than most rattails, with bold black streaks on the head and black and silver barring over most of the body. There is a long bioluminescent organ with two lenses underneath the rear end of the body.
Text from the Wikipedia article “Graceful grenadier”, 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: 1 records
- February: 3 records
- March: 2 records
- April: 0 records
- May: 2 records
- June: 2 records
- July: 6 records
- August: 4 records
- September: 6 records
- October: 2 records
- November: 5 records
- December: 3 records
Depth and water temperature
Depth
Mostly recorded at 255–540 m · Deepest record: 600 m
Water temperature
Recorded in surface water of 17–28 °C
Names and classification
- English
- Delicate Whiptail, Graceful Grenadier
Names in 1 more languages
- Japanese
- Onisujidara, オニスジダラ
Other scientific names: Hymenocephalus (Hymenogadus) gracilis, Hymenocephalus gracilis
Similar species
- Bollons' rattail
Coelorinchus bollonsi
- Banded Whip-tail
Coelorinchus fasciatus
- Innotable Whiptail
Coelorinchus innotabilis
- Serrulate Rattail
Coryphaenoides serrulatus
- Four-rayed Rattail
Coryphaenoides subserrulatus
- deepsea whiptail
Lepidorhynchus denticulatus
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).
- 75 open-data records from 1908 to 2003.
- Species data updated November 3, 2026.
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