Triangle crab

Eurynolambrus australis

Crustaceans
IUCN: Not evaluated

Usual depth0–80 m
Water temperature11–18 °C
Best monthsJanuary, May, and December
How commonRare

Photo credit: no rights reserved, uploaded by Liam Clayton Media · CC0 1.0 · iNaturalist

About this species

Eurynolambrus australis, commonly known as the triangle crab, and by its Māori name riangi, is a small species of crab that is widespread throughout New Zealand. It is the only species in the genus Eurynolambrus.

Text from the Wikipedia article “Eurynolambrus”, 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: 23 records
February: 14 records
March: 7 records
April: 12 records
May: 18 records
June: 6 records
July: 13 records
August: 6 records
September: 9 records
October: 7 records
November: 6 records
December: 19 records

Depth and water temperature

Depth

Mostly recorded at 0–80 m · Deepest record: 83.5 m

0–10 m: 10 records
10–20 m: 5 records
20–30 m: 2 records
30–40 m: 0 records
40–50 m: 5 records
50–60 m: 2 records
60–70 m: 0 records
70–80 m: 2 records
80–90 m: 3 records

Water temperature

Recorded in surface water of 11–18 °C

10–12 °C: 4 records
12–14 °C: 5 records
14–16 °C: 6 records
16–18 °C: 14 records
18–20 °C: 1 records

Photos

(c) Luca Davenport-Thomas, some rights reserved (CC BY) · CC BY · iNaturalist
(c) Saryu Mae 前朝琉, some rights reserved (CC BY) · CC BY · iNaturalist
(c) Luca Davenport-Thomas, some rights reserved (CC BY) · CC BY · iNaturalist
(c) Kelvin Perrie, some rights reserved (CC BY) · CC BY · iNaturalist
(c) Robert Briggs, some rights reserved (CC BY-SA) · CC BY-SA · iNaturalist
no rights reserved · CC0 1.0 · iNaturalist

Names and classification

English: Triangle crab

Similar species

Southern spider crab
Jacquinotia edwardsii
Great spider crab
Leptomithrax gaimardii
Golden Decorator Crab
Naxia aurita
Leptomithrax australis
Leptomithrax longipes
Leptomithrax mortenseni

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).
71 open-data records from 1933 to 2013.
Species data updated November 2, 2026.

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