A postflexion larva (15.6mm standard length) of a skilfish, Erilepis zonifer (Lockington, 1880), is described from off Iwate, northeastern Japan. This is the first report of the larval stage of this species. The larva of E.zonifer is similar to that of the only confamilial species, the sablefish Anoplopoma fimbria (Pallas, 1814), in having a laterally compressed body, two dorsal fins, large pectoral fins, no head spination, and heavy pigmentation of the body and the distal part of the pectoral fin. The longer pectoral fin and deeper body of E.zonifer, coupled with distinctive meristic counts, separate the larvae of these two species of the family Anoplopomatidae.

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A pelagic juvenile (43.0mm standard length) of the morid Gadella jordani (Bohlke and Mead, 1951) was collected from Kagoshima Prefecture, southern Japan. It has a characteristically elongated body, long dorsal and anal fin bases with 73 rays in each fin, the anus located more anteriorly than the origin of the second dorsal fin, a ventral light organ, and no chin barbel. We describe the morphology of this specimen and also present a color photograph of it in life. This is the first report of any early life stage in this species.

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The poorly known dasyatid stingray Dasyatis laevigata Chu, 1960 is redescribed on the basis of a single syntype and 18 recently collected specimens from Ariake Sea, Japan, and the East China Sea. Sexual dimorphism and growth-related variation in taxonomic characters are considered, and life history characteristics, such as distribution and size at maturity, are clarified on the basis of an additional 464 specimens.

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We report on two allied genera of the Talitridae from Taiwan: Paciforchestia Bousfield, 1982 and Lanorchestia gen. nov. Taiwanese specimens representing Paciforchestia are not identified to species due to their poor condition, but examination of these specimens has led us to revise the generic diagnosis of Paciforchestia. Specimens of the two species assigned to Paciforchestia, P.klawei (Bousfield, 1961) (type species of the genus) and P.pyatakovi (Derzhavin, 1937), were also examined. Lanorchestia kanoi gen. et sp. nov. is described from Lanyu Island (=Lan-Hsu), a small island of Taiwan. Lanorchestia is compared with and differentiated from the following allied genera: Parorchestia Dana, 1853, Agilestia Friend, 1982, Hawaiorchestia Bousfield, 1984, Tasmanorchestia Friend, 1987, Bousfieldia Chou and Lee, 1996, and Paciforchestia.

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A new species of bopyrid isopod, Probopyrus iriomotensis sp. nov. parasitizing palaemonid freshwater shrimps of the genus Macrobrachium, is described based on material from Iriomote Island, Ryukyu Islands, southwestern Japan. The new species most commonly infects the branchial chambers of Macrobrachium shokitai Fujino and Baba, 1973, but rarely also M.formosense (Bate, 1868). The new species is similar to Probopyrus ascendens (Semper, 1880), P.gangeticus Chopra, 1923, and P.giardi Weber, 1892, but can be distinguished from them by a combination of characters of the pleomere and pleotelson, relative body width, and the degree of deflection of the body axis. This is the first species of Bopyridae to be recorded from a freshwater environment in Japan. In addition, the generic assignment of two marine species of Probopyrus is questioned, and the date of authorship of P.marinus Nierstrasz and Brender a Brandis, 1923 is clarified.

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Morariopsis grygieri sp. nov. is described from two caves in the town of Taga, in the mountainous flanks of ancient Lake Biwa, and a key to world species of Morariopsis is provided. Other known members of the genus live in two disjunct areas: three species are benthic dwellers in Lake Baikal, while three live in subterranean waters of the western Balkan Peninsula, in Slovenia and Croatia. In order to confirm the phylogenetic relationships of our new species, and to test whether the Baikal and Balkan groups represent one colonisation event each or more, a cladistic analysis was performed on all seven species and two outgroup taxa, based on 21 morphological characters. The resulting cladogram shows that the ingroup is well defined by at least two synapomorphies, and that the Baikal group is also a well-defined Clade, probably representing a single colonisation event. The three Balkan species are only remotely related to each other, and all probably represent separate colonisations. The new species is not closely related to any of its presently known congeners, and also represents a separate colonisation event. We speculate that the ancestor of this species first colonised benthic habitats of ancient Lake Biwa, during its tectonic formation, and from there colonised subterranean waters in its surroundings during the major climatic changes of the Quaternary. We suggest, as a novel hypothesis, that ancient lakes also act as biodiversity pumps for subterranean habitats.

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