REDISCOVERY OF THE RARE EUXANTHINE CRAB, GUINOTELLUS MELVILLENSIS SERÈNE, 1971 (DECAPODA, BRACHYURA, XANTHIDAE) IN THE PHILIPPINES BY JOSE C. E. MENDOZA 1,2,4 ), MARIVENE R. MANUEL-SANTOS 3 ) and PETER K. L. NG 1 ) 1 ) Department of Biological Sciences, Faculty of Science, National University of Singapore, 14 Science Drive 4, Singapore 117543, Rep. of Singapore 2 ) Institute of Biology, College of Science, University of the Philippines, Diliman, Quezon City, Philippines 1101 3 ) Carcinology Section, Zoology Division, National Museum of the Philippines, Padre Burgos Street, Ermita, Manila, Philippines 1000 ABSTRACT Guinotellus melvillensis Serène, 1971, is a rare euxanthine crab (Brachyura, Xanthidae) described from only a single juvenile male specimen devoid of pereiopods, and has never been reported since. Thirteen additional specimens, all adults, have since been discovered, allowing us to make a complete description of its adult morphology. The affinities of this unique, monotypic genus are also discussed. RÉSUMÉ Guinotellus melvillensis Serène, 1971, est un crabe Euxanthinae rare (Brachyura, Xanthidae) qui a été décrit à partir d’un unique spécimen juvénile mâle dépourvu de péréiopodes, et qui n’a jamais été signalé depuis. Treize spécimens, tous adultes, ont été découverts, nous permettant de faire une description complète de la morphologie de l’adulte. Les affinités de ce genre monotypique, unique, sont aussi discutées. INTRODUCTION Owing to the unusual shape of its carapace and the presence of subhepatic cavities, Serène (1971) described a new genus and new species, Guinotellus melvillensis, on the basis of a single juvenile crab specimen collected from the Balabac Strait, southern Palawan, in the Philippines. A more detailed description with additional illustrations of the third maxillipeds, antennulal fossae, subhepatic 4 ) e-mail: jcmendoza@nus.edu.sg © Koninklijke Brill NV, Leiden, 2009 Crustaceana 82 (1): 39-51 Also available online: www.brill.nl/cr DOI:10.1163/156854008X363687