Black-throated Threefin

Helcogramma decurrens

Fish
IUCN: Least concern

Usual depth2–12 m
Water temperature17–26 °C
Best monthsJanuary
How commonOccasional

Photo credit: no rights reserved · CC0 1.0 · iNaturalist

About this species

The black-throated triplefin is a species of triplefin blenny in the genus Helcogramma. It was described by Allan Riverstone McCulloch and Edgar Ravenswood Waite in 1918. This species occurs along the western and southern coasts of Australia where it is found down to depths of 13 metres (43 ft) in both the intertidal and subtidal zones where it hides among algae growing on rocky substrates.

Text from the Wikipedia article “Black-throated triplefin”, licensed CC BY-SA 4.0. Read the article

Where and when

Where it has been recorded

Worldwide

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Best months

Worldwide (open data)

January: 402 records
February: 121 records
March: 178 records
April: 117 records
May: 41 records
June: 30 records
July: 20 records
August: 18 records
September: 40 records
October: 69 records
November: 159 records
December: 123 records

Depth and water temperature

Depth

Mostly recorded at 2–12 m · Deepest record: 31.5 m

0–10 m: 46 records
10–20 m: 8 records
20–30 m: 0 records
30–40 m: 1 records

Water temperature

Recorded in surface water of 17–26 °C

16–18 °C: 12 records
18–20 °C: 30 records
20–22 °C: 352 records
22–24 °C: 15 records
24–26 °C: 2 records

Photos

(c) Belinda Forbes, some rights reserved (CC BY) · CC BY · iNaturalist
(c) Grady Duffy, some rights reserved (CC BY) · CC BY · iNaturalist
(c) Grady Duffy, some rights reserved (CC BY) · CC BY · iNaturalist
(c) Belinda Forbes, some rights reserved (CC BY) · CC BY · iNaturalist
(c) Debra Baker, some rights reserved (CC BY) · CC BY · iNaturalist
no rights reserved · CC0 1.0 · iNaturalist
(c) ttsquid, some rights reserved (CC BY) · CC BY · iNaturalist

Names and classification

English: Black-throated Threefin, Black-throated Triplefin, Blackthroat Threefin, Gulf Threefin, Southern Triplefin, Threefin, Yellowback Threefin

Other scientific names: Vauclusella calva

Similar species

Candystriped Triplefin
Helcogramma striata
Red-eye Threefin
Helcogramma ellioti
Triangle Triplefin
Helcogramma inclinata
Maldives Triplefin
Helcogramma maldivensis
Hotlips
Helcogramma rharhabe
Whitespot Triplefin
Helcogramma albimacula

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).
1,446 open-data records from 1935 to 2023.
Species data updated November 3, 2026.

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