Dynomenidae and Dromiidae (Decapoda, Brachyura) from Guam, Philippine Islands, Tonga and Samoa Author Mclay, Colin L. Zoology Department, Canterbury University, Christchurch, PB 4800 (New Zealand) c. mclay @ zool. canterbury. ac. nz. text Zoosystema 2001 23 4 807 856 journal article 6377 10.5281/zenodo.4689208 72669070-3bd6-41be-bd47-f386c83d0927 1638-9387 4689208 Dynomene praedator A. Milne-E>dwards, 1879 Dynomene praedator A. Milne-Edwards, 1879: 8 , pl. 14, figs 20-26. — McLay 1999: 481 , figs 3b, 8a-b, 11, 12 d, 14 b, 17 b, 19 a-g. MATERIAL EXAMINED. — Guam . Piti Reef, 13°27’N , 144°47’E , among rocks, 1.5 m , 22.VII.1993 , 2 8.5 × 6.5 ( GUM 268). — Among rocks, 1.5 m , 22.VII.1993 , 1 13.0 × 10.3 mm ( GUM 270). — Among rocks, 1 m , 1.VIII.1993 , coll. H. T . Conley, 1 7.8 × 7.0 mm ( GUM 300). — Outer reef margin, 1 m under rubble pile, 1-4 m , IV.1998 , 1 9.5 × 7.5 mm , coll. S. Norby, 1 (ovig.) 9.7 × 7.1 mm ( UGI no registration number, ZRC 2000.0743). SIZE . — Maximum size for males is 13.5 × 10.7 mm , and for females 12.0 × 9.6 mm . All specimens from Guam are smaller than these sizes. The above oviger- ous female, with about 160 eggs ready to hatch, was captured during April and so conforms to the reproductive period recorded elsewhere of from January to June. DEPTH AND HABITAT. — Depth range intertidal to approximately 50 m among coral. All the Guam specimens came from shallow water, 1- 4 m . DISTRIBUTION. — D. praedator is a widespread Indo- West Pacific species which has already been recorded from the Mariana Islands (see McLay 1999 ). DISCUSSION Dynomene praedator has been recently redescribed and illustrated by McLay (1999) where a full synonymy can also be found. D. praedator , along with D. hispida , are the two most common shallow water dynomenids throughout the Indo- West Pacific, so it is surprising that D. hispida has not yet been found in Guam . D. hispida has been collected from the northern Mariana Islands of Maug East and Maug North ( Takeda et al. 1994 ) so it is likely to be present in Guam . If it is found, it will mean that Guam will have the richest shallow water dynomenid fauna (four species) in the world. While all the specimens came from among rocks, one specimen was excavated from 1 m below the rubble surface. This is a much neglected habitat, where we do not usually expect to find crabs.