La pêche électrique pratiquée dans les eaux intérieures des cinq archipels de la Polynésie française a permis d'inventorier 16 espèces de crustacés d'eaux douces. Parmi les 16 espèces mentionnées dans le présent article, une espèce est endémique: Caridina rapaensis de Rapa et de Rurutu. Six sont localisées dans la région Pacifique et neuf dans la région Indo-Ouest Pacifique. Une nouvelle espèce a été trouvée: Macrobrachium sp. Elle colonise les rivières de Moorea et des îles marquisiennes. Trois nouvelles espèces ont été pêchées pour la première fois en Polynésie française: Caridina serratirostris (Moorea et Tubuaï), Ptychognathus easteranus (Rurutu et Hiva Oa), Varuna litterata (Tahiti et Moorea). La répartition altitudinale de ces 16 espèces dans les îles étudiées a été établie et la biomasse des principales espèces dans les rivières de Tahiti-Moorea a été calculée.

Due to the sparse and unstable nature of insular freshwater habitats, marine larval dispersal of amphidromous species is considered a critical element of population persistence. We assessed population genetic structure of freshwater prawn Macrobrachium lar across its range that encompasses two biogeographic barriers: the vast open ocean separating Western and Central Pacific regions and the Indo-Malay archipelago separating Indian and Pacific oceans. A total of 173 samples collected from 21 islands throughout the Indo-Pacific were sequenced at 16S and 28S rDNA. We observed distinct genetic isolation of populations located at the eastern and southwestern edge of the species range but no evidence of an effect of the IndoPacific barrier. Differentiation patterns are consistent with a stepping-stone model of dispersal. Genetic differences of Central Pacific populations may reflect founder events associated with colonization of isolated islands, or be a signature of a past bottleneck after population depletion caused by drastic climatic events.

Anguillid eels were sampled from permanent rivers in the Ré union and Mauritius islands, western Indian Ocean, with a standardized electrofishing method. A. marmorata was very dominant, corresponding to 91.7 and 90.

External morphology has always been the first criterion used to separate species of shrimps, especially in the freshwater genus Caridina H. Milne-Edwards, 1837, but more doubts have been expressed regarding the relevance of some of the morphological characters. We collected 27 specimens of Caridina from seven different localities during field work conducted on the island of Pohnpei (Federated States of Micronesia). After genetic verification that they all belonged to the same species, 19 morphological variables were measured and correlated with the elevation of the collecting stations using correlation analyses. We provide evidence that the length of the rostrum 2 showed strong negative correlation with the elevation. This could be explained either by the physical stress exerted on the rostrum by the stronger water currents in the stations at a higher elevation, as a defence against predators in the lower stations, or a combination of both possibilities.The taxonomy of these shrimps is thus challenging and should not rely only on rostrum length, but on other characters such as the number of teeth on the dorsal margin of the carapace, which is not correlated with rostrum length and therefore, with the environment.

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Lentipes kaaea, new species, is described on the basis of 28 specimens collected from high gradient streams occurring in eastern slope region of North Province on New Caledonia and streams in the island nation of Vanuatu. Lentipes kaaea, new species, is distinguished from all other congeners by the following combination of characteristics: males and females with a single pair of fleshy lobes associated with and attached basally with urogenital papilla, lobes always apparent in males and only apparent in gravid females; usually 17 (17-18) pectoral rays; usually 10 (9-10) segmented rays in second dorsal fin; caudal peduncle with cycloid scales, few ctenoid scales may be present along midline in females, between belly and first dorsal fin ctenoid scales with 3 to 5 large spike like ctenii present on males and absent in females; cephalic sensory pore system with pores A, B, C, D, F, H, K, L, N and O, pore D singular with all other pores paired, oculoscapular canal divided into posterior and anterior canals between pores H and K; males bright red to purplish on head and on posterior half of body, second dorsal fin with a black spot between spine and ray 1, individuals may have more than one spot present, first dorsal fin bluish to purplish and usually without spots, anal fin reddish to purplish basally and bluish distally; females usually whitish with variable tan to brownish markings that may include a distinct lateral band and a spot at medial base of caudal fin, above midline dusky bars and bands may be present, dusky saddles may be present dorsally, fin rays and spines with basal half slightly brownish and distally without pigment, membrane in all fins generally clear. Key words :Lentipes kaaea, new species, New Caledonia, Vanuatu, Gobiidae, Sicydiinae. Bull. Fr. Pêche Piscic. (2002) RÉSUMÉLentipes kaaea, espèce nouvelle, est décrite à partir de 28 exemplaires collectés dans les rivières de la côte est de la Province nord de la Nouvelle-Calédonie et du Vanuatu. Cette espèce se distingue des autres par la combinaison des caractéristiques suivantes : mâles et femelles avec une seule paire de lobes charnus associés à la papille urogénitale, ces lobes étant toujours apparents chez le mâle et chez la femelle gravide ; 17 (17-18) rayons aux nageoires pectorales, 10 (9-10) rayons segmentés à la seconde nageoire dorsale ; le système de pores sensoriels céphaliques a les pores A, B, C, D, F, H, K, L, N et O, le pore D est simple alors que tous les autres sont doubles ; les mâles sont rouges brillants sur la tête et la partie médiane de la partie postérieure du corps, ils possèdent en général une tache noire sur la seconde dorsale tandis que la première n'en possède pas et est de couleur bleutée ; la nageoire anale est rosée avec sa marge distale bleutée à blanche ; la femelle est gris beige.

Following recent (2014–2017) collections made in the Solomon Islands by the MNHN and the NGO ESSI, we provide a checklist of the species of amphidromous freshwater shrimps of the genus Caridina H. Milne Edwards, 1837 from this region. Using morphological as well as molecular data in an integrative taxonomic perspective, we found a total of 24 species, including 11 new for science, that are described or re-described, illustrated and discussed in relation to their habitat and distribution. Newly described species are Caridina barakoma sp. nov., C. choiseul sp. nov., C. intermedia sp. nov., C. maeana sp. nov., C. nana sp. nov., C. piokerai sp. nov., C. pisuku sp. nov., C. paratypus sp. nov., C. poarae sp. nov., C. sikipozo sp. nov. and C. turipi sp. nov. Caridina gueryi Marquet, Keith & Kalfatak, 2009 is re-validated as a species distinct from C. buehleri Roux, 1934. Lectotypes are designated for C. mertoni Roux, 1911 and C. papuana Nobili, 1905. Diagnoses for 6 informative species groups are provided: C. brevicarpalis group, C. gracilirostris group, C. nilotica group, C. typus group, C. serratirostris group and C. weberi group. A map of the species distribution in the Solomon Islands, as well as the phylogenetic relationships between the species and their relatives, are provided.