A new family, Podosphaerasteridae, is proposed for the valvatid asteroid genus Podosphaeraster, with a new species of the genus from southern Japan, western North Pacific. Podosphaeraster differs from the fossil genus Sphaeraster and other valvatid families by the overall body form and the skeletal structure. The new Japanese species, P. toyoshiomaruae sp. nov., differs from the previously known species of Podosphaeraster principally in number and size of granules on the abactinal and actinal plates, number of adambulacral spines, retention of perforations in terminal plates, and ratio of horizontal diameter to vertical diameter. Podosphaeraster toyoshiomaruae was collected together with abundant sponges and probably lives closely associated with sponge. This is the first record of the genus Podosphaeraster from Japanese waters.

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For many years it had been assumed that the oligochaete collection of Professor Hideji Yamaguchi had been destroyed by a large earthquake in Hokkaido, Japan, in 1968, but the majority of the collection was rediscovered recently. The branchiobdellidan portion of the slide collection has been examined, the specimens identified as far as possible, and the materials deposited in the museum of the Division of Biological Science, Graduate School of Science, Hokkaido University, Japan. All of the species described by Yamaguchi between 1932 and 1940 have been identified, and their collection sites plotted. In addition, specimens were found of species not described until much later, Holtodrilus truncatus (Liang, 1963), Branchiobdella macroperistomium Liu and Zhang, 1983, and B. monodonta Liu and Zhang, 1983. To place the information obtained in this re-examination in context, the literature on East Asian branchiobdellidans is reviewed in detail.

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Parhyale hachijoensis sp. nov., from the Izu Islands of Japan, is characterized by the following features : in maxilla 1 the palp is 2-articulate with the articulation near the middle of the palp ; in gnathopod 1 one of the palmar corner spines on the propodus is displaced to the posterior margin ; in pereopods 6 and 7 the posterior margins of the propodi are lined with 4 and 3 groups of spines, respectively ; in uropod 1 the peduncle has an ordinary distolateral spine ; and in uropod 3 the inner ramus is vestigial and fused to the peduncle. Parhyale philippinensis sp. nov., from two sites in the Philippines, is characterized by the following features : in maxilla 1 the palp is 1-articulate with a constriction slightly beyond the middle of the palp ; in gnathopod 1 the palmar corner spines of the propodus are close together ; in pereopods 6 and 7 the posterior margins of the propodi are lined with 5 groups of spines ; in uropod 1 the peduncle has an elongate distolateral spine ; and in uropod 3 the inner ramus is fully articulated. The fact that both new species have the propodal posterior margins lined with a number of groups of spines in pereopods 6 and 7 suggests that they belong to the P. hawaiensis complex.

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The rare squaloid shark Oxynotus japonicus Yano and Murofushi, 1985 has been known only from the male holotype since its original description. Six female specimens were collected from Suruga Bay and the Enshu-nada Sea, Japan, and detailed descriptions of them are given here. The female reproductive organs of this species are described for the first time and size at maturity is discussed.

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Genetic differences between two color morphotypes of Sebastes scythropus (Jordan and Snyder, 1900) were estimated from partial sequences of the mitochondrial (mt) DNA tRNA genes and control region. A phylogenetic tree was constructed using the neighbor-joining method and incorporating sequences from the congeners S. inermis Cuvier, 1829, S. joyneri Gunther, 1878, S. owstoni (Jordan and Thompson, 1914), and S. thompsoni (Jordan and Hubbs, 1925), as well as Sebastiscus marmoratus (Cuvier, 1829) (outgroup). Individuals of each color morphotype of S. scythropus were reciprocally monophyletic, with bootstrap values of 100%. The mean sequence difference between the two morphotypes was 10.1%, which was comparable to, or even larger than, the interspecific differences among the other four Sebastes species (5.9-10.8%). Sympatric occurrence of the two morphotypes with such a high degree of genetic differentiation indicates that they are reproductively isolated and stand as distinct species.

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Synagrops serratospinosus, previously known from the Philippines and Japan, is recorded from Australia for the first time based on 20 specimens from the Northwest Shelf and the Coral Sea. The Australian specimens differ from the Philippine specimens in having a modally higher number of gill rakers on the lower arm of the first gill arch.

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Mitochondrial 16S rRNA sequences were compared between two color-types (type-A and type-B) of the labrid fish Choerodon robustus (Gunther, 1862) collected from the Pacific coast of Japan and the Ryukyu Islands. The two types differ in coloration of the opercle lower margin and caudal fin. Two type-A specimens each had a unique haplotype, whereas only two haplotypes were found among nine type-B specimens. The amount of mean pairwise sequence divergence within each of the two color-types was very small (0.16% in type-A, 0.035% in type-B), much less than that between the two color-types (4.3%). Phylogenetic analyses using maximum parsimony (MP) and neighbor-joining (NJ) methods, with a haplotype of Choerodon azurio (Jordan and Snyder, 1901) as an outgroup, showed that the haplotypes of each color-type were reciprocally monophyletic with 100% bootstrap values. The sequence differences between the two color-types ranged from 4.2% to 4.6%, such being comparable to those between C. azurio and each of the two color-types (5.3-5.7%). These results indicate that the two color-types of C. robustus represent two distinct species.

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Two new paraulopid fishes, Paraulopus okamurai sp. nov. and P. novaeseelandiae sp. nov., are described on the basis of specimens collected from 235-553 m depth in eastern Australian and New Zealand waters. Within Paraulopus, the two new species are most similar to P. nigripinnis (Gunther, 1878) in having a supraocular ridge, 4.5-5.5 transverse scale rows above the lateral line, and a large body size. Paraulopus okamurai, P. novaeseelandiae, and P. nigripinnis differ from one another in the following characters : caudal-fin coloration (black with a transverse white band on the upper lobe and a white tip on the lower lobe in P. okamurai ; white with a black posterior margin on the upper lobe and a short, dark, oblique band on the lower lobe in P. novaeseelandiae ; white with a black posterior margin on both lobes in P. nigripinnis), counts of pectoral-fin rays (modally 17 in P. okamurai, 18 in P. novaeseelandiae, and 16 in P. nigripinnis), and predorsal scales (modally 17 in P. okamurai, 18 in P. novaeseelandiae, and 14 in P. nigripinnis).

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