The morphologies of the male, mature larva, and nest of Ropalidia plebeja (Saussure, 1862, non 1863) are described for the first time. A nest of R. celebensis Van der Vecht, 1941 and the mature larvae and details of nest structure of R. rufoplagiata (Cameron, 1905) are also described for the first time. Taxonomic notes and a key to species of the R. plebeja group, which includes R. plebeja, R. celebensis, R. rufoplagiata, R. andamanensis Das and Gupta, 1989, R. turneri Richards, 1978, and R. cristata Kojima, 1989, are provided. New synonymies proposed are R. gravelyi Dover and Rao, 1922 and R. rufoplagiata nursei Van der Vecht, 1941, both under R. rufoplagiata. The colony populations of R. plebeja suggest that this species probably has a nearly solitary life habit. Character states supporting the monophyly of the R. plebeja species group, and those linking it to the R. gracilis (Smith, 1859) species group, are examined in detail.
Seventeen species of the mite family Phytoseiidae are reported from West Malaysia. Of these, 13 named species are recorded for the first time in Malaysia. Amblyseiulella thoi sp. nov. and Platyseiella acuta sp. nov. are described. Phytoseius (Phytoseius) huangi Ehara, 1970 is a junior synonym of Phytoseius hawaiiensis Prasad, 1968.
A new species of echinoderid kinorhynch, Echinoderes aureus, is described and illustrated using a differential interference contrast microscope with Nomarski optics. The kinorhynchs were collected from washings of a brown alga, Padina arborescens Holmes, growing in tide pools in Tanabe Bay, Honshu Island, Japan. Diagnostic characters of E. aureus are the presence of middorsal spines on segments 6-10, lateral spines/tubules on segments 4 and 7-12, a pair of remarkably large subcuticular scars in a subventral position on segment 3, and an incomplete midventral articulation on segment 4. The positions of numerous sensory-glandular organs, the sizes of various lateral spines/tubules, and the shapes of the terminal tergal and sternal extensions are also diagnostic. Echinoderes aureus constitutes the 59th valid species of the genus Echinoderes and the 15th species described from the Pacific Ocean. This is the fourth representative of Pacific kinorhynchs found only in the intertidal zone and the second Pacific Echinoderes living on macroalgae in tide pools. A dichotomous key to all 59 species is provided.
The brackish-water ostracod fauna was surveyed for almost two years at 17 points representing typical environments, such as foreshore sand flat, back marsh, and tidal creek, in the intertidal zone of the Obitsu River Estuary, Chiba Prefecture, central Japan. Twenty-one species belonging to 17 genera and 10 families were identified. In addition to the description of one new genus, Palusleptocythere, and four new species, Pontocythere xiphoidea, Palusleptocythere migrans, Loxoconcha kosugii, and Cytherois ikeyai, chitinous parts are described for the first time for four previously described species, Spinileberis pulchra Chen, 1982, Angulicytherura ? miii (Ishizaki, 1969), Semicytherura wakamurasaki Yajima, 1982, and Loxoconcha pulchra Ishizaki, 1968. Furthermore chitinous parts of male Dolerocypria mukaishimensis Okubo, 1980 are also shown for the first time. This is the first report on an ostracod fauna from a shallow estuarine environment in either Japan or any adjacent area.