Reference 10799

A large collection of fossil decapods has yielded several new occurrences for late Pleistocene deposits of Guam, United States Territory.Neocallichirus? sp., Myra fugax, Thalamita crenata, Rhinolambrus pelagicus, Scylla serrata, Calappa hepatica, Carpilius sp., Actaeodes sp., and several indeterminate chela fragments are herein reported as FOSSIL from Guam for the first time.Emended descriptions and additional illustrations are provided for the previously reported taxa, Macrophthalmus latreillei and Podophthalmus vigil.Macrophthalmus guamensis is herein synonymized with M.definitus.Carcinoplacoides is herein synonymized with Libystes.Carcinoplacoides flottei is also synonymous with Libystes nitidus and becomes the junior synonym of the latter species.Myra brevisulcata, M.subcarinata, and M.trispinosa of the Pliocene Miri Formation (Morris and Collins, 1991) are herein synonymized; M.brevisulcata becomes the senior synonym.The fauna is unusual because most of the taxa are comprised of many more male than female individuals; the percentage of males within the preserved population ranges from 50 to 89 percent in various species.The late Pleistocene fauna of Guam appears to have been derived from the Tethyan and Indo-Pacific regions, as is typical of Indo-Pacific faunas of Recent oceans (Schweitzer, 2001).Many of the genera and even some species appear to have evolved as early as the Miocene in the western Tethyan area of southern Europe.These findings support the assertion that most decapod genera and many species that first appeared in the Miocene survive into the Recent (Schweitzer, 2001)