Notes on some Indo-Pacific Pontoniinae, XII. The re-examination of Pontonia? brevirostris Miers, 1844, with the designation of a new genus Platypontonia (Decapoda Natantia, Pontoniinae). Crustaceana

In the course of checking the pontoniid shrimp fauna of the Seychelles Islands, the author had occasion to examine the specimens of Pontonia? breviro.rtri.r first described by Miers (1884) from the material collected by H.M.S. "Alert " in 1882 and preserved in the collections of British Museum (Natural History), London. Miers ' doubts about the systematic position of the specimens are con-firmed and a new genus is now made for this species. The opportunity is taken to amplify Miers ' short description and to provide more detailed illustrations of its morphological features. I wish to express my sincere thanks to Dr. A. L. Rice for permission to examine and report upon these specimens. Platypontonia gen. nov. Diagnosis of genus.- A commensal pontoniid shrimp of uncertain association. Body robust, depressed and smooth. Rostrum very short, dorso-ventrally flattened, triangular and toothless. Antennal spine present; hepatic spine and supra-orbital spines absent. Pleura of abdominal segments rounded. Telson broad, with larg