Thomisus

Abstract: Pollinators possess several antipredator adaptations that minimise predation risk during foraging. In addition to morphological adaptations, hoverflies might have behavioural antipredator adaptations. We conducted three field experiments to investigate whether the “hesitation behaviour” of hoverflies Sphaerophoria spp., moving backwards and forwards in front of a flower, is effective in avoiding ambush predators on flowers. First, we compared the behaviour of different flower visitors, including several bees and other hoverflies, with Sphaerophoria spp. behaviour. Only Sphaerophoria spp. exhibited the hesitation behaviour in front of flowers. The flight behaviour was observed more frequently before landing on flowers than on leaves. Second, we investigated rejection by Sphaerophoria spp. to artificially placed corpses of the crab spider Thomisus labefactus. The rejection rate of flowers with a crab spider placed on or under it was significantly higher than that of non-treated flowers. Moreover, the presence of a spider on the flower decreased the number of hesitation displays, compared with non-treated flowers. Finally, to determine whether hesitation behaviour could be a consequence of floral assessment, we investigated hoverfly rejection of previously foraged flowers. Sphaerophoria spp. did not reject flowers that had been visited by the same individual or conspecifics within 3 min. We suggest that hesitation behaviour may be adaptive, enabling assessment of predation risk and hence avoiding ambush predators on flowers.

Abstract: The crab spiders (Araneae: Thomisidae) collected from Hainan Island, China are studied. A total of 25 genera, 43 species are reported, including 12 new species, two new combinations and one new synonym. The new species are: Borboropactus brevidens sp. nov., Borboropactus edentatus sp. nov., Borboropactus longidens sp. nov., Lycopus longissimus sp. nov., Lysiteles furcatus sp. nov., Lysiteles leptosiphus sp. nov., Oxytate multa sp. nov., Ozyptila biprominula sp. nov., Paraborboropactus liangweii sp. nov., Paraborboropactus oblatus sp. nov., Thomisops altus sp. nov., Thomisus eminulus sp. nov. The species Philodamia gongi (Yin et al, 2004) comb. nov. is transferred from Tmarus and Sinothomisus hainanus (Song, 1994) comb. nov. from Xysticus. The species Lysiteles guangxiensis He & Hu, 1999 is a junior synonym of Alcimochthes limbatus Simon, 1885. The true females of B. hainanus Song, 1993 and Lysiteles minusculus Song & Chai, 1990 are described for the first time.

Abstract: Spiders of the families Thomisidae and Philodromidae (Arachnida, Araneae) mainly collected in the mountainous areas of Iran in 1978 are taxonomically studied and classified into 21 species of 10 genera. Most species are illustrated and described on the basis of the present specimens. Except for only two species, Xysticus kulczynskii Wierzbicki 1902 and Synaema globosum (Fabricius 1775), already known from this country, 19 species are new records to the Iranian fauna. Of these, 14 species, Tmarus stellio Simon 1875, Xysticus ninnii Thorell 1872 (subsp. fusciventris Crome 1965), X. cristatus (Clerck 1758), X. kochi Thorell 1872, X. gallicus Simon 1875, Oxyptila nigrita Thorell 1875, Heriaeus spinipalpus Loerbroks 1983, Misumena vatia (Clerck 1758), Pistius truncatus (Pallas 1772), Runcinia lateralis (C. L. Koch 1838), Thomisus hilarulus Simon 1875, Philodromus longipalpis Simon 1870, P. cespitum (Walckenaer 1802), and P. emarginatus (Schrank 1803), are previously known to science, while five species are regarded as new and described under the names Xysticus marusiki, X. logunovi, X. pieperi, Oxyptila makidica, and O. lutosa.

Abstract: The spiders are known as poisonous arthropods, but they also act as the predator or biological pests control agent. Their 23 species belonging to 15 genera and 09 families were reported during 2009-2010 from FR Peshawar, FATA, Pakistan. The reported families Clubionidae, Scytodidae and Sprassidae covered each 4%, Araneidae, Gnaphosidae, Pholicidae and Salticidae each 9%, Thomisidae 13% and Lycosidae 43% biodiversity of spiders of FATA. However, the largest spider collected was huntsman, Isopoda tuhodnigra (Barrion) with total body length 15.80±0.83 mm. Moreover, the smallest spider was wolf spider, Pardosa birmanica (Simon) with total body length 4.20±1.30 mm. Further, the crab spiders, Thomisus pugilis (Stoliczka), T. spectabilis (Doleschall) and Diaea evanida (Thorell) were the most colorful species belonging to family Thomisidae. A detail study is required for further exploration of spider fauna of FATA.