Twelve new species from three genera of Gnathiidae are described: Caecognathia rhektos , Elaphognathia aldabrae , E. gladia , E. ramosa , Gnathia antonbruunae , G. eumeces , G. glauca , G. luxata , G. serrula , G. somalia , G. stoddarti , and G. zanzibarensis . Most are from the western Indian Ocean, with one from Thailand. Gnathia nkulu Smit & Van As, 2000 , is newly recorded from Madagascar. Keys to the six species of Elaphognathia and 20 species of Gnathia from the Indian Ocean are presented.

ABSTRACT Eighteen species of sergestid shrimps are reported from 72 benthic trawl, towed net, dip net, and seine collections made by R/V Albatross in the Philippines in 1907–1910. Included are one species each of Acetes , Allosergestes , Deosergestes , Neosergestes , Parasergestes , Sergestes , and Sicyonella and eleven species of Sergia . Sergia foresti , taken from off Mindanao, Philippines, is described as new.

ABSTRACT The sergestid genus Sergestes is restricted in definition, and five new genera erected: Allosergestes , Deosergestes , Eusergestes , Neosergestes , and Parasergestes . These are defined in terms of 23 morphological characters, including features of the appendages, luminescent organs, and petasmata. The species belonging to each are listed, and the type species for each designated. Diagnoses for the remaining genera in the family, Acetes , Peisos , Petalidium , Sergia and Sicyonella are supplied. A key to the 11 currently recognized sergestid genera is provided.