Biodiversity & Conservation

Slender spider crab - Macropodia tenuirostris

Macropodia tenuirostris

Image Steven Campbell - Macropodia tenuirostris. Image width ca XX cm.
Image copyright information

Distribution map

Macropodia tenuirostris recorded (dark blue bullet) and expected (light blue bullet) distribution in Britain and Ireland (see below)

Why do the maps differ?

Sightings Have you seen Macropodia tenuirostris?
If so please submit your record.

Macropodia tenuirostris is not listed under any importance categories.

Taxonomy icon Taxonomy Taxon English term
Phylum Arthropoda Arthropods, joint-legged animals, e.g. insects, crustaceans & spiders
Class Malacostraca Crabs, lobsters, sand hoppers and sea slaters
Authority (Leach 1814)
Recent synonyms None
Map icon Recorded Distribution in Britain and Ireland Common around the British Isles.
Habitat information icon Habitat information Macropodia tenuirostris has been recorded in depths from about 9 m to 97 m on muddy to hard substrata, in estuaries, and also on colonies of Sertularella spp. at depths down to 300 m.
Text page icon Description Macropodia tenuirostris is reddish brown in colour and has a triangular shaped shell (carapace) that is very narrow at the frontal region. The length of the carapace is around 3.2 cm and the breadth around 1.1 cm. The surface of the carapace has a smooth to slightly granular texture. The snout (rostrum) is thick, very long and is deflected slightly upwards, with numerous prominent hook-setae (hair like structures). The eyestalks are totally visible from above. Second to fifth pairs of limbs (pereopods) are very thin. The fourth segment (from the tip) of the first walking leg is as long as or longer than the combined length of the carapace and the rostrum. The tip of the second leg is the same length as the carapace. The fourth and fifth legs have moderately curved tips (dactylus). Male chelipeds are large and inflated whereas female chelipeds are slender.
Identifying features
  • Triangular shaped carapace.
  • Reddish brown in colour.
  • Rostrum thick and very long, deflected slightly upwards.
  • Second to fifth pair of legs very long and slender.
Additional information icon Additional information The arrangement of spines on the upper surface are diagnostic of species of Macropodia (see Ingle 1980 & 1996 for further details).

This review can be cited as follows:

Rose Edwards 2005. Macropodia tenuirostris. Slender spider crab. Marine Life Information Network: Biology and Sensitivity Key Information Sub-programme [on-line]. Plymouth: Marine Biological Association of the United Kingdom. [cited 25/11/2015]. Available from: <>