A new species of leptostracan, Nebalia kensleyi, is described from the coast of central California. It differs from other species of Nebalia most notably in the shape and color of the pigmented region of the eyes, armature of the antennule and antenna, extent that the carapace covers the abdominal somites, epimeron of pereonite 4, dentition of the protopod of the third and fourth pleopod, details of the pleonite border spination, and length of the terminal seta of the caudal furca.

Afromysis kensleyi, a new species of mysid, was collected from the surf zone bordering sandy beaches in central and southern Oman. It is readily distinguished from six other described Afromysis species by a combination of the form of the eyestalks (two-times long as broad), the absence of reflexed finger-like processes on the dorsal side of the carapace, and the form and arrangement of spines on the telson. Lateral spines on the telson are arranged as a series of four spines near the base and about fifteen spines on the posterior half that become progressively longer and more robust posteriorly. The apex of each lobe on the telson is armed with four spines.

A new species, Lamprops kensleyi, is described based on specimens collected from southern Chile. This is the first unambiguous record of the genus from the southern hemisphere. Lamprops kensleyi is distinguished from all other members of the genus by the combination of an unornamented carapace and 3 terminal setae on the telson.

The genera Membrilopus, previously known from southern Africa, and Regalia, previously known from the western Indian Ocean, eastern Indonesia and northern New Zealand, are reported for the first time in Australian waters. Three new species—Membrilopus kensleyi, Regalia juliana and Rhachotropis elliottana—are described. Membrilopus kensleyi is a scavenger living at the base of the continental slope; Regalia juliana is a sublittoral algaldweller living along the central eastern Australian coast; and Rhachotropis elliottana occurs off the Great Barrier Reef in depths of 500 m.

A third species of the genus Discerceis is described and a new generic diagnosis is offered. The distinctions in the new species are seen in morphological characters of the male, specifically the pleotelson, which bears an elongate, deeply set, apically upturned median tooth in the pleotelsonic notch, and in the uropods, which are much longer relative to the pleotelson as compared to its two cogeners. A key to the known species of the genus is given.

Biremia kensleyi, the second species of its genus and fourth in the Bathynataliidae, is described from the tropical east coast of Australia. Biremia ambocerca Bruce, 1985, also from tropical eastern Australia, is diagnosed and compared with the new species. The family and genus are rediagnosed. Homologies of structures in the mandibles of bathynataliids and serolids are discussed.

Chiridotea caeca dwells in the intertidal zone of sandy beaches where it is shown for the first time to be a predator of sympatric benthic fauna. Laboratory feeding experiments revealed that C. caeca captured and consumed the haustoriid amphipod Amphiporeia virginiana and the polychaetes Scolelepis squamata and Neanthes succinea (an estuarine polychaete). Prey were captured with the first pair of pereopods (gnathopods), often torn and then pressed against the mouthparts where trituration took place prior to ingestion. Examination of the hindgut contents of 539 isopods (immatures and adults) showed that prey consisted primarily of crustaceans (haustoriid amphipods, young-of-the-year Emerita talpoida) and occasionally polychaetes and insects. Mancae were cannibalized in the laboratory. This study indicates that Chiridotea caeca competes with other predators (fishes, shorebirds, various invertebrates) for benthic prey within the surf zone.

Kensleylana briani, new genus, new species, is described from freshwater in the karst caves of the Miravet Ravine, northern Spain. The monotypic genus is characterised by extreme reduction of the pleon, which has all pleonites fused to the pleotelson, with only one short suture marking the division between the pleon and the pleotelson. The genus and species is further characterised by the uropod peduncle being elongate, round in cross-section, extending to the posterior margin of the pleotelson and terminating in a single short stub-like ramus. The appendage morphology is otherwise similar to that of Faucheria Dollfus & Viré, 1905, a monotypic, freshwater, cave-dwelling genus known only from southern France.

Progebiophilus euxinicus (Popov, 1927) is recorded from the north end of the Adriatic Sea, a new geographical record. Progebiophilus bruscai Salazar-Vallejo & Leija-Tristán, 1989, infests Upogebia dawsoni Williams and U. rugosa (Lockington) in the Gulf of California, Mexico, the latter a new host record and from a locality farther north than previously recorded. Progebiophilus upogebiae (Hay, 1917) infests U. affinis (Say) on the east coast of Florida, U.S.A, a new geographical record. Progebiophilus kensleyi infests U. africana (Ortmann) on the southeastern coast of South Africa. Progebiophilus insperatus infests U. paraffinis Williams in São Paulo state, Brazil. Names of some hosts of Phyllodurus abdominalis Stimpson, 1857, are corrected, and the total range of the genus Phyllodurus Stimpson is considered.

Branchial bopyrids were investigated from hermit crabs collected in Singapore in August 2000. Two male and female bopyrid pairs belonging to the genus Asymmetrione were found on Diogenes avarus Heller and described as A. sallyae. One pair of bopyrids from the branchial chamber of Clibanarius infraspinatus Hilgendorf represents a new species of Pseudione that is described as P. kensleyi. This is the first report of isopod parasites on hermit crabs from Singapore and represents the first records of bopyrids from these hermit crab hosts.

The poorly known bopyrid isopod Bopyrophryxus branchiabdominalis Codreanu, 1965 is redescribed based on newly discovered material obtained from hermit crab hosts from several Indo-Pacific localities. The genus Bopyrophryxus Codreanu, 1965 is found to be closely related to the pseudionine genus Asymmetrione Codreanu, Codreanu, & Pike, 1965, with which it shares many characters of both males and females. The subfamily Bopyrophryxinae Codreanu, 1965 is found to be synonymous with the Pseudioninae Codreanu, 1967, although the junior synonym is maintained as the correct name of the taxon because of its extensive use in the literature.

Peracarids are a large group of malacostracan crustaceans whose systematics and phylogeny are uncertain. The present phylogenetic study of peracarids is, to our knowledge, the first that includes full-length nuclear (n) small-subunit (SSU) ribosomal DNA (rDNA) sequences for representatives of every peracarid order. Sequence length varied substantially (1807–2746 base pairs), and two variable regions (V4 and V7) contained long expansion segments. Variable regions also exhibited significantly greater heterogeneity in nucleotide frequencies than did core regions. Maximum-parsimony, maximum-likelihood, Bayesian, and distance phylogenetic estimates indicated a monophyletic Peracarida that excluded the Mysida and included the Thermosbaenacea. This peracarid clade received strong support under Bayesian, maximum-parsimony, and distance analyses, but not maximum likelihood. Further, the thermosbaenacean lineage does not occupy a basal position relative to other peracarids, as suggested by many morphology-based phylogenies. The phylogenetic position of the Mysida within the Malacostraca remains uncertain, but a sister-group relationship between Mysida and Lophogastrida (i.e., a monophyletic Mysidacea) was consistently rejected, a result that also differs from those of most morphology-based phylogenies. High Bayesian clade-credibility support was obtained for an (Isopoda Tanaidacea Cumacea) clade and a (Lophogastrida [Spelaeogriphacea Amphipoda]) clade. Within the peracarid clade, internal branches were considerably shorter than terminal ones, so relationships among some peracarid lineages were equivocal. Data partitions corresponding to stem and loop regions in a secondary-structure model for nSSU rRNA had congruent phylogenetic signal but differed in nucleotide composition and evolutionary model. Maximum parsimony and Bayesian phylogenetic estimates based on the loop partition generally shared more nodes in trees inferred from combined data than did those based on stems, even though the stem partition had roughly twice as many characters.

Coral reef stomatopods from the vicinity of Sodwana Bay, South Africa, are reported. Ten species of Gonodactyloidea from seven genera and four families are represented. All species are new records for Sodwana Bay. Eight species represent new records for South Africa of which one, Pseudosquillisma kensleyi, is new to science. Pseudosquillisma kensleyi is the fourth species in the genus to be recognised, differing from all known congeners in having an inflated and globular, instead of a flattened and subtrapezoid cornea.

Parapasiphae kensleyi, a new species of shrimp (Crustacea: Decapoda: Pasiphaeidae) collected from abyssopelagic waters of the North Pacific Ocean, is described. The new species differs from other members of the genus in having ocular peduncles lacking ocular tubercles. Each ocular peduncle has two separate unpigmented corneas; thus, the shrimp appears from external morphology to have four eyes. A key to the known species of Parapasiphae is provided. A brief discussion is included of possible functions for the unique double eyes seen in this new species.

A new species of bresiliid shrimp, Bresilia briankensleyi, from over 700 m in the central Red Sea, is described and illustrated. Another bresiliid shrimp, Discias musicus Holthuis, is reported from the Red Sea, for its third occurrence and for the first time outside the Western Pacific region.

Chorocaris paulexa, new species, the first member of the genus Chorocaris Martin & Hessler, 1990 reported from the eastern Pacific, is described based primarily on two specimens, one of which is ovigerous, collected by the DSV Alvin at the Homer hydrothermal (black smoker) vent site (17°S) on the southern East Pacific Rise (SEPR). Seven additional (non-type) specimens from other SEPR sites (Rapa Nui, Brandon vents) are also described and compared to the types. The new species is compared to its congeners C. vandoverae Martin & Hessler, 1990, from the Mariana Back-Arc Basin in the western Pacific, and C. chacei (Williams & Rona, 1986), from the Mid-Atlantic Ridge), as well as to Mirocaris fortunata (Martin & Christiansen, 1995) (Mid-Atlantic Ridge). The new species is markedly similar in morphology to both Chorocaris vandoverae and C. chacei, but it can be distinguished from either of those species by a combination of the relatively acute branchiostegal projection of the carapace border, extent of the rostrum, and shape of the antennal scale. The finding extends the known range of the genus Chorocaris ~11,000 km eastward (from the Mariana Back-Arc Basin) and stimulates evolutionary and biogeographic hypotheses to explain this Pacific-wide distribution of a shrimp genus specialized to inhabit hydrothermal vent systems.

New material discovered for the rare species Eutrichocheles modestus allows a detailed study and a comparison with its closely related congener, E. crosnieri Ngoc-Ho, 1998. The taxonomic status of Eutrichocheles Wood-Mason, 1876 and Paraxiopsis de Man, 1905 is discussed. The separation of the two, as proposed by Kensley (1996a), is accepted.

Eucalliax kensleyi, a new species, is described from sublittoral sediment in the Gulf of Aqaba, Red Sea. Of the species presently assigned to the genus Eucalliax Manning & Felder, 1991, the new species appears to be most closely related to E. bulimba (Poore & Griffin, 1979), presently known from a male taken in Moreton Bay and a female taken at Britomart Reef, Queensland, Australia. Eucalliax kensleyi differs from E. bulimba in having a very short subrectangular telson and a triangular tooth on the cutting edge of at least one cheliped.

Thalassinidean shrimp constitute six or seven families of highly specialized burrowing decapod crustaceans. Adaptations to a deep infaunal mode of life, exemplified by the ghost shrimps Callichirus and Callianassa, include an elongate subcylindrical body differentially sclerotized and divided into units functional for life in tubular burrows (i.e., burrowing, locomotion, flexion, pumping, and sealing). Death or molting within burrows may lead to positive biases of preservation of the more heavily sclerotized parts consisting of burrow buttons preserving chelipeds, anterior cephalothoracic regions, posterior abdomen, and walking legs. Thalassinidean chelipeds, particularly the fingers, are among the most common of decapod crustacean body fossils. Illustrations and examples are given to document the full range of fossil remains, including body fossils and trace fossils. An exceptional whole-body thalassinid, Axiopsis eximia, was described by Kensley and Williams (1990) from the Middle Eocene of South Carolina. The specimen is a silicified body fossil preserving virtually the entire animal except distal appendages. This specimen remains the only described silicified thalassinid. This paper is presented as a tribute to Brian Kensley and as closure for the Bishop-Williams collaborations spanning 25 years.

A new squat lobster of the genus Munida was collected during on-going deep-sea expeditions around Taiwan. The new species, Munida rupicola, belongs to the group containing M. microps Alcock, 1894, M. africana Balss, 1913, M. profunda Macpherson & de Saint Laurent, 1991, M. rubella Macpherson & de Saint Laurent, 1991, and M. rubrovata Macpherson & de Saint Laurent, 1991, but is distinct in the combination of the following characters: carapace lacking secondary striae, supraocular spines subparallel, distomesial spine of the second antennal segment not overreaching antennal peduncle, merus of third maxilliped with three marginal spines on flexor margin, and the carpus of cheliped slightly more than 2.5 times as long as wide. The coloration of this new species is illustrated.