A partial revision of the genus Periclimenes Costa, 1884 (Crustacea: Decapoda: Palaemonidae) Author Bruce, A. J. text Zootaxa 2004 582 1 26 journal article 10.5281/zenodo.157391 7c93efa7-47d9-43b2-8703-704f1c472fcf 1175­5326 157391 17D08B02-5D62-4313-B56A-D430D4486D5D Genus Kemponia gen. nov. Diagnosis. Small to medium sized pontoniine shrimps of subcylindrical body shape. Carapace smooth, glabrous, with rostrum well developed, dorsally and ventrally dentate, with or without epigastric or supraorbital, spines, hepatic and antennal spines present, orbit obsolete, inferior orbital angle distinct, anterolateral angle rounded. Abdomen smooth, glabrous, pleura rounded, posterolateral angle bluntly rounded or dentate. Antennule with short stylocerite, statocyst with statolith; flagella well developed, upper ramus with shorter flagellum multi­segmented. Antenna with basicerite with lateral tooth, scaphocerite well developed. Eye well developed, elongate, subcylindrical, cornea globular, ophthalmic somite without median process (= béc ocellaire ). Mandible without palp; molar and incisor processes well developed. Maxillula with feebly bilobed palp. Maxilla normal, with simple palp, basal endite simple, coxal endite obsolete. First maxilliped with simple palp, basal and coxal endites feebly separate, broad, exopod with reduced flagellum, caridean lobe small, broad; epipod large, generally triangular. Second maxilliped with normal endopod, dactylar segment narrow, exopod well developed, epipod small, subrectangular, with rudimentary podobranch. Third maxilliped normal, ischiomerus not fused to basis, exopod well developed, generally with numerous plumose setae distally, coxa with rounded lateral plate, generally with small or rudimentary arthrobranch. Thoracic sternites narrow, fourth with slender finger­like median process, posterior sternites without acute processes. First pereiopods slender, chela with fingers simple. Second pereiopods well developed, frequently slender, elongate, generally equal or unequal, similar or dissimilar; major chela fingers without molar process and fossa. Ambulatory pereiopods slender, dactyls simple, without basal process. Uropod with protopodite distolaterally dentate; exopod with small tooth and mobile spine distolaterally. Telson with two pairs of dorsal spines, three pairs of posterior spines. Type species. By present designation, Anchistia grandis Stimpson, 1860 . Etymology. Named in honour of Stanley Wells Kemp, F.R.S., ( 1882–1945 ), in recognition of his seminal 1922 study Notes on Crustacea Decapoda in the Indian Museum. XV. Pontoniinae . Combined with part of the name Pontonia Latreille, 1829 . Gender: feminine. Biology. Mainly free­living, shallow water species, occupying a wide variety of habitats. Some “commensal” species associated with scleractinian, antipatharian and gorgonian hosts ( Kemponia amymone , K. kororensis and K. nilandensis ). The only American species ( K. americanus ) has been reported in association with anemones and crinoids, but these associations may have been accidental as the species has been frequently captured under free­living circumstances. Systematic position . Kemponia appears very closely related to Palaemonella Dana, 1852 : type species P. t e n u i p e s Dana, 1852, sharing with that genus the conspicuous median sternal process on the fourth thoracic sternite but differing in the absence of a mandibular palp. It is also close to Periclimenes Costa, 1844 sensu restricto ; type species P. amethysteus Risso, 1826 . The mandibular palp is also absent in the species of this genus which lacks the median sternal process on the fourth thoracic sternite. In Periclimenes the ambulatory dactyls are biunguiculate or more ornate, except for a few species in which the accessory tooth on the corpus has been secondarily lost. In all Kemponia species the dactylus is simple, generally long and slender and not short and strongly curved. The ambulatory propod is spinulate. In the closely related Harpilius species the propod is distally setose and devoid of spines and the dactylus short and strongly curved.