crabs

Halicarcinus cookii (Filhol, 1885)
Class Malacostraca Order Decapoda Infraorder Brachyura Family Hymenosomatidae
classification
pillbox crab
morphology surface substrate habitat
1 cm
main image: Shane Ahyong
Flattened carapace, octagonal, narrowing anteriorly, slightly wider than broad. Upper carapace
surface smooth, without felt. Sides of carapace with tooth on each side. Rostrum originating at
carapace level and forming three short points at about eye-level. Walking legs with row of triangular
teeth on last segment. Highly varaiable colour according to habitat, ranging from lime green to
almost black, with or without whitish mottling. Chelipeds usually banded.
Endemic, widely distributed around NZ, including Stewart and Chatham Islands. Amongst seaweeds
(Corallina sp. and Hormosira banksii), mussels and fouling on open and rocky coasts. Intertidal,
shallow water.
It could also be……….
Halicarcinus spp.
Halimena aoteoroa
Melrose, M. J. (1975) The marine fauna of New Zealand: Family Hymenosomatidae (Crustacea, Decapoda, Brachyura). New Zealand Oceanographic Institute
Memoir 34: 1–123.
Yaldwyn, J.C., Webber, R.W. (2011) Annotated checklist of New Zealand Decapoda (Arthropoda: Crustacea). Tuhinga 22: 171-272.
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