Opisthoncus L. Koch, 1880

Taxonomy Opisthoncus is found in , New Guinea and New Britain. Australia has thirty species (see Appendix 1), however several of these are of doubtful status or may be misplaced (Gardzińska and Żabka, 2013; Whyte and Anderson, 2017). The is part of an Australasian clade (Maddison et al 2008) including Abracadabrella, Apricia, Clynotis, Holoplatys, Huntiglennia, Ocrisiona, Paraphilaeus, Paraplatoides, Pungalina, Tara, Trite and Zebraplatys (Maddison 2015). Further information on the genus and described species in Australia can be found in Richardson and Żabka (2017) and Whyte and Anderson (2017). Examples of live Opisthoncus Illustrators (and ©) R. Whyte (T), I.R. Description Macaulay Opisthoncus spp. are medium-sized to large , ranging in body length from 5 to 13 mm, their morphology varying quite markedly between species. The carapace is high, with a bulge on the midline between the posterior lateral eyes in most species. The head, viewed from above, varies in shape, from roundish, almost rectangular to trapezoid. Chelicerae in the female have a subdivided (fissident) retromarginal tooth and two promarginal teeth. The pattern in the males is variable. Though primarily fissident, species can also be unident or plurident, sometimes with additional spurs. The shape and size of the chelicerae is extremely variable. The first pair of legs is longer and stronger than the others.

The male’s palp has an embolus, in some species, slender and curving clockwise around the Aspects of the general morphology of Opisthoncus tegulum, in others, short and thick. The tegulum is small and round, or large and elliptical. The Illustrators (and ©) R. Whyte, B.J. Richardson palpal tibia has a single, hook-like or straight, somewhat conical retro-lateral tibial apophysis. (TM, ML) (CSIRO), M. Zabka (diag.) (QMB) The female has two poorly-sclerotised epigynal atria with copulatory openings on their lateral sides. From these, coiled insemination ducts lead postero-laterally to rounded spermathecae near the midline. The epigastric fold has a median cleft or uptucking of varying size. Biology Found on grass, shrub and tree foliage in forests, woodlands, mangroves, heathlands and grasslands, occasionally in houses. Bites have been reported, without medical consequence. Distribution Palp morphology of Opisthoncus Illustrators (and ©) R. Whyte, M. Zabka The genus has been collected across Australia, except for extremely arid parts of the interior. It (diag,) (QMB) is also found in New Guinea and New Britain. References Davies, V.T. & Żabka, M. 1989. Illustrated keys to the genera of jumping spiders (Araneae: Salticidae) in Australia. Memoirs of the Queensland Museum 27, 189-266.

Gardzińska, J. & Żabka, M. 2013. Redescription of the genus Opisthoncus L. Koch, 1880 (Araneae: Salticidae). Zootaxa 3717, 401–447. Examples of the epigyne morphology of Maddison, W.P. 2015. A phylogenetic classification of jumping spiders (Araneae: Salticidae). Opisthoncus Journal of Arachnology 43, 231-292. Illustrators (and ©) R. Whyte (TL), B.J. Richardson (BL) (CSIRO), M. Zabka (diag,) Maddison, W.P., Bodner, M.R. & Needham, K.M. 2008. Salticid phylogeny revisited, with (QMB) the discovery of a large Australian clade (Araneae: Salticidae). Zootaxa 1893, 49-64.

Richardson, B.J. & Żabka, M. 2017. Salticidae. Arachnida: . Canberra, Australian Faunal Directory. Australian Biological Resources Study, at https://biodiversity.org.au/afd/taxa/SALTICIDAE. Whyte, R. and Anderson, G. 2017. A field guide to the spiders of Australia. Clayton: CSIRO Publishing 451pp. * The information sheet should be read in the context of the associated diagrams and photographs. Diagrams explaining anatomical terms can be found in the ‘Salticidae’ pictures at the beginning of the list of genera. Appendix 1. Included species from Australia. Opisthoncus abnormis Opisthoncus albiventris Opisthoncus alborufescens Opisthoncus barbipalpis Opisthoncus bellus Opisthoncus bitaeniatus Opisthoncus clarus Opisthoncus confinus Opisthoncus delectabilis Opisthoncus devexus Opisthoncus grassator Opisthoncus keyserlingi Opisthoncus kochi Opisthoncus lineativentris Opisthoncus machaerodus Opisthoncus magnidens Opisthoncus mandibularis Opisthoncus mordax Opisthoncus necator Opisthoncus nigrofemoratus Opisthoncus pallidulus Opisthoncus parcedentatus Opisthoncus polyphemus Opisthoncus quadratarius Opisthoncus rubriceps Opisthoncus serratofasciatus Opisthoncus sexmaculatus Opisthoncus tenuipes Opisthoncus unicolor Opisthoncus versimilis