Northern smoothtongue

Leuroglossus schmidti

Fish
IUCN: Not evaluated

Usual depth0–483 m
Water temperature5–21 °C
Best monthsMay and September
How commonCommon

Photo credit: (c) Steve Taylor, some rights reserved (CC BY) · CC BY · iNaturalist

About this species

The Northern smoothtongue is a type of deepwater fish that can grow to a length of 15 centimetres (5.9 in) TL. The fish are native from the Pacific Ocean to Oregon, United States and also to the Gulf of California where they are found at depths of 100 to 690 metres.

Text from the Wikipedia article “Northern smoothtongue”, 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: 10 records
February: 226 records
March: 166 records
April: 445 records
May: 670 records
June: 351 records
July: 178 records
August: 47 records
September: 768 records
October: 12 records
November: 264 records
December: 3 records

Depth and water temperature

Depth

Mostly recorded at 0–483 m · Deepest record: 6,500 m

0–10 m: 2,084 records
10–20 m: 7 records
20–30 m: 8 records
30–40 m: 8 records
40–50 m: 8 records
50–60 m: 9 records
60–70 m: 41 records
70–80 m: 34 records
80–90 m: 15 records
90–100 m: 33 records
100–110 m: 44 records
110+ m: 1,311 records

Water temperature

Recorded in surface water of 5–21 °C

4–6 °C: 78 records
6–8 °C: 221 records
8–10 °C: 22 records
10–12 °C: 95 records
12–14 °C: 2 records
14–16 °C: 0 records
16–18 °C: 0 records
18–20 °C: 0 records
20–22 °C: 1 records

Names and classification

English: Northern smoothtongue, northern smoothtongue, nothern smoothtongue

Names in 2 more languages

French: leuroglosse luisant
Japanese: Togariichimonjiiwashi, トガリイチモンジイワシ

Other scientific names: Bathylagus schmidti

Similar species

Snubnose Blacksmelt
Bathylagoides wesethi
Eared blacksmelt
Lipolagus ochotensis
Antarctic Big-eyed Smelt
Bathylagus antarcticus
Slender blacksmelt
Bathylagus pacificus
Longsnout blacksmelt
Dolicholagus longirostris
Bigscale deepsea smelt
Melanolagus bericoides

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).
6,702 open-data records from 1956 to 2023.
Species data updated November 4, 2026.

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