Two new spider species of the genera Glenognatha and Pachygnatha (Araneae: Tetragnathidae) from Japan

Abstract

Two new species of the spider family Tetragnathidae (Araneae) from Japan are described: Glenognatha osawai sp. nov. and Pachygnatha monticola sp. nov. Glenognatha osawai is described on the basis of specimens collected on the Ogasawara Islands (Nakodo-jima and Muko-jima Islands). This new species is similar to G. argyrostilba (O. Pickard-Cambridge 1876) and G. tangi (Zhu, Song & Zhang 2003) in general appearance and cheliceral morphology, but it can be distinguished by the shapes of conductor, cymbium, and paracymbium of the male palp. Pachygnatha monticola is described from Nagano Prefecture, a mountainous region of Honshu Island. This new species resembles P. quadrimaculata (Bösenberg & Strand 1906), but it can be distinguished by the morphology of chelicera and fang and by the shapes of embolus and paracymbium of the male palp.