PORT PHILLIP BAY


Estuarine Sea Spider 

Amarinus laevis (Targioni Tozzetti, 1877)

View scientific description and taxonomy

Scientific Details

Carapace circular to oval, wider than long; surface flat or slightly concave with well defined grooves; rostrum spade-like, deflexed, concave laterally, extending over eyestalks, separated from dorsal surface by ridge or groove or both. Antennal spines acute and prominent (ventral view of carapace). Maxillipeds 3 slightly separated medially. Chelipeds stouter than walking legs, especially in male; chelae of large males with a pulvinus (a sac arising between bases of fingers).

Source: Poore, G.C.B. (2004) Marine decapod Crustacea of southern Australia. A guide to identification (with chapter on Stomatopoda by Shane Ahyong). CSIRO Publishing, Melbourne, 574 pp.

Taxonomy

Phylum:
Arthropoda
Subphylum:
Crustacea
Class:
Malacostraca
Subclass:
Eumalacostraca
Superorder:
Eucarida
Order:
Decapoda
Suborder:
Pleocyemata
Infraorder:
Brachyura
Family:
Hymenosomatidae
Genus:
Amarinus
Species:
laevis

Other Names

  • False Spider Crab

General Description

Antennal spines acute and prominent (ventral view of carapace); chelae of large males with a pulvinus (a sac arising between bases of fingers). Buff-coloured. Carapace up to 22 mm carapace wide.

Biology

Flat-backed crabs or false spider crabs or sea spiders as they are variously named, have a very flat carapace, with a well-defined edge all around, and very long spindly legs. Most are small and the round carapace is less than 15 mm across. They inhabit algae or hide under stones.

Habitat

Muddy estuaries to depths of 7 m.

Soft substrates

Coastal shores

Distribution guide

Southern temperate oceans, including southern Australia.

Species Group

Crabs and allies Crabs

Depth

Shore (0-1 m)
Shallow (1-30 m)

Water Column

On or near sea floor

Max Size

22 mm

Diet

Organic matter

Harmful

Not harmful but a nip from large claws could be painful

Commercial Species

No

Global Dispersal

Native to Australia

Species Code

MoV 986

Conservation Status

  • DSE Advisory List : Not listed
  • EPBC Act 1999 : Not listed
  • IUCN Red List : Not listed

Author

article author Taylor, J.

Dr. Jo Taylor is the Sciences Collections Online Coordinator at Museum Victoria.

Author

article author Poore, G.C.B.

Dr. Gary Poore is Principal Curator Emeritus at Museum Victoria.

citation

Cite this page as:
Taylor, J. & Poore, G.C.B., 2011, Estuarine Sea Spider, Amarinus laevis, in Taxonomic Toolkit for marine life of Port Phillip Bay, Museum Victoria, accessed 19 Oct 2017, http://portphillipmarinelife.net.au:8098/species/5476

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