A salticid spider species, Cosmophasis lami Berry, Beatty & Prószynski 1997 is newly recorded from Japan. This species is easily distinguishable from the other Japanese salticid spiders by having: orange body; male palp with circular bulb, long spiniform embolus and three tibial apophyses; epigynum with visible paired-semicircular internal canals and elongated copulatory openings.
Euscorpiops alexandreanneorum sp. n., belonging to the family Euscorpiidae Laurie, is described on the basis of a single male specimen collected in the north of the Province of Luangprabang, District of Muang Ngoi, Laos. The new species is characterized by slender body, very elongated pedipalps and particular trichobothrial pattern. This new scorpion taxon may represent yet another endemic element for the fauna of Laos.
A new species of ant-mimicking jumping spiders, Myrmarachne tamsuiensis, is described using specimens from Tamsui, Taiwan. The female of the species is in external appearance similar to that of M. vulgarisa, whose female is known. However, they are distinguishable from each other mainly by the structure of the epigyne.
The spider genus Rhythela was taxonomically revised. Male palpal structure is employed for morphological examination because the structure of female receptacle is an unreliable taxonomic character due to its large variation. Four of seven known species, R. nishihirai, R. iheyana, R. sasakii, and R. ishigakiensis were remained as independent species. Ryuthela secundaria and R. owadai were newly synonymized with R. sasakii, and R. tanikawai was synonymized with R. ishigakiensis. The male of R. iheyana was described for the first time.
The molecular analysis using the partial sequencing data of mt-DNA COI gene and nuclear 28S-rRNA gene is conducted to infer the phylogeney and geographical genetic variations in the genus Ryuthela. The genus Ryuthela is suggested to be the monophyletic and the most derived group in the subfamily Heptathelinae. Ryuthela iheyana, R. sasakii and R. ishigakiensis are monophyletic groups, respectively, but R. nishihirai seems to be paraphyletic to R. iheyana. Ryuthela spiders appear to be diverged into many phylo-groups with strong geographic associations.
A new species of the genus Marpissa (Araneae: Salticidae), Marpissa mashibarai sp. nov., is described using specimens obtained from Yamaguchi and Tokyo Prefs., in Honshu Island, Japan. This species exhibits poorly marked sexual dimorphism in body size and coloration. Both sexes have the black median line on dorsum of abdomen, allowing us to distinguish it from the other congeneric species.