Spiders of the genus Cyrtarachne are known to feed mainly on moths. To determine whether these spiders attract male moths of a particular group like bolas spiders, we collected prey caught by Cyrtarachne and moths flying in the field. Contrary to our expectation, prey moths comprised both sexes of various species, with the sex ratio of 0.77 in favor of females. Furthermore, sex ratio of prey and that of moth flying in the field did not differ significantly. These results suggest that Cyrtarachne does not seem to attract male moths.
To study the kleptoparasitic behavior of web spiders invading webs abandoned by adult female Metleucauge kompirensis (Araneae: Tetragnathidae), I investigated the numbers of prey insects and intruding spiders on host webs. Tetragnatha praedonia (3.0-9.0mm long) and M. kompirensis spiderlings (1.0-1.5mm long) invaded the host-absent webs in early morning. The number of insects in abandoned webs decreased rapidly in the morning because of theft by intruders. The number of intruders increased gradually as time progressed, and in the afternoon most of them constructed small webs inside the abandoned webs. Larger intruders often drove smaller ones away, and acquired more insects than the latter. Prey theft in unoccupied host webs may be an effective strategy to obtain prey, because these webs are not defended.
A new species of oribatid mite belonging to the genus Dyobelba is described from Korea. Dyobelba paucituberculata sp. nov. can be distinguished from the other species of Dyobelba by the complete absence of prodorsal enantiophyses B, D, epimeral and dorsosejugal enantiophyses E2, V and discidium, the presence of microtubercles at the bases of epimeral setae of 1, 2, 3-series and 4b, and the presence of two setae on trochanter IV. Some information on generic diagnosis and distribution of hitherto known species of Dyobelba are given.
Four new species of the spider family Sparassidae are described from Taiwan: Pseudopoda serrata sp. nov. (male and females), Pseudopoda recta sp. nov. (female), Sinopoda exspectata sp. nov. (male), and Olios scalptor sp. nov. (male). These represent first records of the three genera for Taiwan. A record of Heteropoda venatoria (Linné 1767) is also reported.
Keys and brief descriptions of 17 species of the genera Robertus, Enoplognatha, Steatoda and Crustulina are given. A new species, Robertus yasudai, is described from the alpine snow-bed communities of Mts. Daisetsu, Hokkaido. A Chinese species, Enoplognatha lordosa Zhu & Song 1992, is recorded for the first time from Japan. Enoplognatha abrupta (Karsch 1879) and Clubiona parvula (S. Saito 1933) are newly transferred from Steatoda. Six species names are newly synonymized: Enoplognatha submargarita Yaginuma & Zhu 1992 with E. margarita Yaginuma 1964; E. japonica Bösenberg & Strand 1906, E. dorsinotata Bösenberg & Strand 1906 and Steatoda albimaculosa (S. Saito 1934) with E. tecta (Keyserling 1884); and E. transversifoveata (Bösenberg & Strand 1906) and E. hangzhouensis Zhu 1998 with E. abrupta (Karsch 1879). Two species names, S. japonica (Dönitz & Strand 1906) and S. minus (Dönitz & Strand 1906), are nomina dubia.
Five species of the family Liocranidae and two species of the family Corinnidae are reported. Phrurolithus vulpes n. sp. is described from Hiroshima Prefecture, Japan. Phrurolithus sinicus Zhu & Mei 1982, P. taiwanicus Hayashi & Yoshida 1993, P. labialis Paik 1991, and Corinna gulosa (Thorell 1878) are recorded from Japan for the first time. The genus Corinna is newly added to the Japanese fauna. Phrurolithuslynx Kamura 1994 is newly recorded from Taiwan. Males of Phrurolithus taiwanicus and Castianeirashaxianensis Gong 1983 are described for the first time.
Twelve new species are described from Japan under the names, A. nojimai, A. tsurusakii, A. ryukyuanus, A. borealis A. iriomotensis, A. yasudai, A. hoshi, A. komi, A. ogatai, A. miyashitai, A. mayumiae, A. amabilis. In addition, A. acusisetus Zhu & Song 1994 is newly recorded from Japan..