The Victorian naturalist . ria An introduction, check list and key to adults BY Geoff Wescott* Introduction After several early works on theshore crabs of Victoria (Fulton andGrant 1901, 1906a, 1906b; Ward 1929)very few studies were published untilthe compilation of species hsts forPort Phillip Bay (Griffin and Yaldwyn1971) and Westernport Bay (MarineStudy Group of Victoria 1971). Thispaper brings together the results ofthese papers and provides a key to theidentification of Victorian shore crabs(brachyurans). A check list and someinformation on the general ecology ofthese crabs are also inclu
The Victorian naturalist . ria An introduction, check list and key to adults BY Geoff Wescott* Introduction After several early works on theshore crabs of Victoria (Fulton andGrant 1901, 1906a, 1906b; Ward 1929)very few studies were published untilthe compilation of species hsts forPort Phillip Bay (Griffin and Yaldwyn1971) and Westernport Bay (MarineStudy Group of Victoria 1971). Thispaper brings together the results ofthese papers and provides a key to theidentification of Victorian shore crabs(brachyurans). A check list and someinformation on the general ecology ofthese crabs are also included. The true crabs, or Brachyura(brachys: short; oura: tail) are onemajor group (or section) of the Rep-tantia (walking) decapod (ten-legged)Crustacea. The other decapod groupsare the crayfish and lobsters (Macrura)and the half crabs and hermit crabs(Anomura). Brachyurans can be re-cognised by the presence of five pairsof Hmbs, a fused head and thoraxcovered by a carapace, and a distinc-tive but reduced, recurved Figure 1. The anomuran Lomis hirta or hairystone crab (scale line 1 cm). Some anomurans such as Lomis hirtathe hairy stone crab (Figure 1) can bemistaken for true crabs, but a Hmbcount and check of the abdominalregion will show that only four pairsof walking legs are visible, instead offive as in the true crabs. Only the truecrabs (brachyurans) will be consideredin this paper. Crabs always have a calcified cara-pace and a pair of stalked eyes whichcan be retracted into hollow orbits atthe front of the carapace. Near theeyes are two pairs of short sensoryantennae. The mouth is complex andbordered by six pairs of appendages,the outer three (the maxillipeds) be-ing modified thoracic appendages. Theshape and structure of the maxillipedsare influenced by the habitat and eco-logy of the crab. The first pair of legsis modified as chelipeds (pincers ornippers) and they are usually largerin the male. The sexes are also separ-able by the shape of the abdominalflap on
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Keywords: ., bookcentury1800, bookdec, booksubjectnaturalhistory, bookyear1884
