The Japanese mayfly genus Cincticostella is taxonomically revised. The four currently recognized species are Cincticostella (Cincticostella) elongatula (McLachlan, 1875) (=okumai Gose, 1980, syn. nov.), C. (C.) levanidovae (Tshernova, 1952), C. (C.) nigra (Ueno, 1928), and C. (C.) orientalis (Tshernova, 1952) (=tshernovae (Bajkova, 1962). The lectotype and paralectotypes of Ephemerella nigra are designated from the syntypes of Ueno. Specimens treated as C. (C.) nigra by many authors are identified with C. (C.) elongatula. All species are redescribed based on examined types and newly collected specimens. Keys are given to all stages : imagoes, subimagoes, nymphs, and eggs. Illustrations, complete synonymies, and distributional records are included for all the species, and the life histories of two species, C. (C.) elongatula and C. (C.) nigra, are presented.
A species of mite of the genus Holostaspella (Acari : Macrochelidae), collected from the ventral body surface of dung beetles in East Kalimantan, Indonesia, is described as new to science. This species, H. katakurai sp. nov., is similar to H. mirabilis Petrova and Taskaeva, 1964, but differs from the latter in the number of preanal setae on ventrianal shield and ornamentation of sternal shield. The present new species provides an exception to the general correlation between phoresy and absence of paranal extensions of the cribrum in the genus.
The present paper contains descriptions of the following ostracod taxa from subterranean waters of Western Australia : Meridiescandona lucerna n. gen., n. sp ; M. facies n. gen., n. sp., and Deminutiocandona mica n. gen., n. sp. They all belong to the subfamily Candoninae, and these findings bring the number of genera of Candoninae to 24. Meridiescandona is characterized by decorated valves, a 6-segmented antennula, and full development of furcal elements. Deminutiocandona stands apart from other candonine genera by having a 5-segmented antennula, a reduced anterior furcal claw, and 4+2 rows of spines on the Zenker's organ. The morphologies of the new genera are discussed and compared with those of the other known genera of this subfamily.
The euryalinid genus Asterostegus (Echinodermata : Ophiuroidea) has been known only from a single specimen of the type species A. tuberculatus, collected in South African waters. A second species, Asterostegus maini, is now described from the Cook Islands, South Pacific Ocean. Asterostegus maini differs from the type species in having tubercles more or less restricted to the outer half of the radial shields, a wider bare dorsal arm surface, often more than two tubercles on the proximal dorsolateral plates, and a single row of ventral disc plates interradially.
Eighteen specimens of the helmet gurnard, Dactyloptena tiltoni Eschmeyer, 1997, collected from Tosa Bay, represent the first record of the species from Japan. A redescription of the species is given. Most specimens from Tosa Bay are larger than the types. The lateral line condition, including tubules covered by body scales, and fresh coloration are described for the first time.
A single specimen of a rare nomeid fish, Cubiceps paradoxus Butler, 1979, collected from Ukui, Wakayama Prefecture, Japan, is the first record of the species from the Western Pacific, previous records having been restricted to California and the central North Pacific. A description of the specimen and a photograph in fresh condition (coloration previously unknown) is given, the following differences from congeneric species being noted : teeth absent on vomer and basihyal, 91 or 92 lateral line scales, eye small (orbit diameter 16.9-18.5% of head length), snout long (31.8-32.3% of head length), distance between posterior end of upper jaw and anterior margin of orbit almost equal to orbit diameter, third predorsal and first proximal pterygiophore of dorsal fin between second and third neural spines, and 11-13 upper and lower procurrent caudal rays.