Records of tile Western Australian MusCllm Supplement No. 52: 159-164 (1995). Salticidae (Arachnida: Araneae) of Oriental, Australian and Pacific Regions, XI. A new genus of Astieae from Western Australia Marek Zabka Zaklad Zoologii WSRP, 08-110 Siedlce, Poland Abstract - Megaloastia mainae gen. et sp. nov., an unusuallong-Ieged spider from Western Australia is described and figured. Remarks on morphology, behaviour and evolution of Salticidae are presented. INTRODUCTION Diagnosis In comparison to some other spider families, the A web-building spider. Legs very long, in males representatives of Salticidae are well defined and up to 4.5 centimeters, thin. Genitalia similar to easy to recognize. They have compact body form, some representatives of Astieae, fovea deep and unique eye pattern, short and stout legs, rather wide, chelicerae of plurident pattern. simple genitalia and complex mating behaviour. They are cursorial long-sighted jumpers, hunting Description actively during the day. Salticids may Medium to large salticid. Cephalothorax robust. communicate by stridulation, substrate and web Cephalic part distinctly elevated, posterior eyes set vibration, visual and chemical signals (Jackson on tubercles. Thorax with gentle posterior slope, 1982, 1986a 1987; Maddison and Stratton 1988). oval, fovea deep. Abdomen elongate. Clypeus low, They live solitary, communal and (perhaps) even about 15% of anterior median eyes diameter. social existence (Jackson 1986c; Maddison 1987). Chelicerae robust, inclined anteriorly, with Salticidae may be found on vegetation, open plurident dentition. Maxillae and labium elongate, ground, on/under rocks and stones, on tree trunks, the first twice as long as wide. Sternum wide, with under bark, in leaf litter. Many salticid genera small marginal indentations, its anterior border mimic other arthropods (Elgar 1993), mostly ants, little wider than base of labium. Legs extremely but also flies (Morrison 1981), wasps (Reiskind long, slender, spread laterally, armed with 1976; Zabka 1992), beetles and pseudoscorpions numerous spines (especially tibiae and metatarsi). (Platnick 1984). The spider described here is Male palpal organ with single tibial apophysis, certainly one of the most spectacular jumping embolus short and wide. Tegulum without spiders and seems an interesting model for apophyses, distal cymbium elongate, tapering. behavioural and evolutionary research. Epigyne with caudal lobe, internal genitalia simple in structure, spermathecae one-chambered. MATERIAL AND METHODS The paper is based on the specimens collected in Relationships, Biology and Distribution the remote Kimberley region of Western Australia The last fifteen years showed the importance of and deposited in Western Australian Museum, behavioural research for phylogenetic consid­ Perth (WAM). Methods of specimen examination, erations. Despite their cursorial way of life, many terminology and measurement taken were salticids spin retreats, nests and even webs described earlier (Zabka 1990). (Jackson 1988, 1989) and it seems very likely that Abbreviations used: AEW - anterior eyes width, early ancestral salticids were web-builders and ag - accessory gland, AL - abdomen length, CL web-invaders that evolved acute vision and cephalothorax length, CW - cephalothorax width, became cursorial hunters (Jackson and Blest 1982; EFL eye field length, fd - fertilization duct, m ­ Jackson 1986b; Jackson and Hallas 1986). In most metatarsus, p - prolateral spines, PEW - posterior cases, the web-building Salticidae represent eyes width, r - retrolateral spines, t - tibia. Pluridentati division. Only a few belong to Fissidentati and Unidentati, the latter being the most derived. The field observations of Megaloastia Megaloastia gen. novo are very fragmentary but they prove its web­ Type species building behaviour, the character being very Megaloastia mainae sp. novo important, but difficult to comment without further 160 M. Zabka Figures 1-5 Megaloastia mainae sp. nov., 0 holotype: 1, dorsal aspect; 2, frontal view; 3, cheliceraI dentition; 4, general appearance; 5, first leg, retrolateral view. New genus of Astieae 161 research. The genus has very distinctive morpho­ Pa ra types logical similarities to the Australasian Astieae Australia: Western Australia: 10, CALM site (Wanless 1988). The caudal lobe of epigyne, simple 28/3, 4 km W. of King Cascade, 15°36'5, 125°15'E, internal genitalia and plurident cheliceral dentition 12-16 June 1988, T.A. Weir (WAM 93/1690); 3CiJ, are found in Astia, Arasia and SOlldra. The structure N. of Larryoo, 14°51'5, 126°49'E, underside of large of male palps is similar to that in Astia and He/pis. boulder, creek bed, 13 June 1992, MS Harvey, J. The legs, however, are much longer than in any M. Waldock (WAM 93/1691-3). known salticids and make the genus so distinctive. Megaloastia has been recorded on webs constructed Diagnosis under large boulders from a few localities in The species can be distinguished by male palpal Kimberleys, Western Australia. organ (Figs 6-8) and female genitalia (Figs 10-14). Etymology Description The generic name is a combination of words "megas" = large, and Astia, a possible relative, and Male IlOlotype (Figs 1-2, 4) it is feminine in gender. Cephalothorax wide and robust, cephalic part distinctly elevated, posterior eyes on tubercles. Eye field chestnut-coloured, eye surrounds black with Megaloastia mainae sp. novo scarce white hairs. Thorax with gentle posterior Figures 1-16 slope, oval and wide, brown, with central yellow stripe. Fovea deep and vast. Abdomen elongate, Material Examined grey-brown with dirty-yellow central pattern. Dark and light surfaces covered with brown and white Holotype hairs respectively. Clypeus and chelicerae dark­ 0, Mt Trafalgar, Western Australia, Australia, brown, the latter with plurident dentition (Fig. 3). 15°17'5, 125°04'E, 12 June 1988, BY Main (WAM Maxillae and labium long, dark-brown with lighter 93/10). tips. Sternum wide, grey-brown, marginally darker, venter anteriorly dirty-brown, further Allotype dirty-beige, darker centrally. Legs (Fig. 5) CiJ, same data as holotype (WAM 93/11). extremely long and slender, spread laterally, armed Figures 6-8 Megaloastia malllae sp. nov, 0 holotype: palpal organ. 162 M. Zabka 10 Figures 9-16 Megaloastia mainae sp. novo 9-12, '? allotype: 9, dorsal aspect; 10, 11, epigyne and internal genitalia; 12, cheliceral dentition. 13-16, '? paratype: 13, 14, epigyne and internal genitalia; 15, dorsal aspect; 16, first leg. New genus of Astieae 163 with long spines. First legs proximally dark-brown, Etymology distally gradually lighter, their index (CL -:- leg The specific name is proposed in honour of Or length) to 8.7. Other legs lighter, from brown to Barbara York Main, an Australian arachnologist, yellow. Dorsal coxae, trochanters and proximal one of the collectors of the material studied. femora yellow, patellae yellow medially. Palpal organ clothed with long light and brown hairs, its structure showed in Figs 6-8. ACKNOWLEDGEMENTS Tibial and metatarsal spination: tI-II: pl-l-l-1-1, Dr Mark Harvey and Ms Julianne Waldock sent rl-l-1-1-1; mI-II: pl-l-1-1, rl-l-l-l; tIll-IV: pl-0-0­ specimens for study and Mark Harvey provided 0-1, rl-0-0-0-l; mIll-IV: pl-0-0-l, rl-0-0-1. information on habitat and biology. Dr David Dimensions (mm). Legs: (from femur to tarsus): Richman and an anonymous referee provided I: 12.76 + 4.40 + 15.80 + 9.88 + 1.84 = 44.68, useful comments on the typescript. II: 8.66 + 3.04 + 9.42 + 6.84 + 1.52 = 29.48, Ill: 8.20 + 2.58 + 8.66 + 7.75 + 1.67 = 28.86, IV: 7.90 + 2.43 + 8.66 + 8.96 + 1.52 =29.47. REFERENCES CL 5.01, CW 4.56, AEW 3.49, PEW 2.81, EFL 2.28, Elgar, M. (1993). Inter-specific associations involving AL 6.08. spiders: kleptoparasitism, mimicry and mutualism. Memoirs ofthe Queensland Museum 33: 411-430. Female allotype (Fig. 9) Jackson, RR (1982). The behavior of communicating in Eye field orange, eye surrounds dark-brown with jumping spiders (Salticidae). In Witt, P.N. and whitish, yellow and longer brown hairs. Thorax Rovner, J.s. (eds), Spider Communication: Mechanisms and Ecological Significance: 213-247. Princeton yellow-orange with brownish pattern, covered University Press, Princeton, New York. with sparse white and brown hairs. Abdomen Jackson, RR. (1986a). Use of pheromones by males of covered with sparse brown hairs, centrally yellow, Phidippus jolmsoni (Araneae, Salticidae) to detect laterally grey-brown with light spots. Spinnerets subadult females that are about to molt. Joumal of dirty-yellow. Clypeus dark-orange with whitish Araclmology 14: 137-139. and yellow hairs. Chelicerae (Fig. 12) and maxillae Jackson, R.R. (1986b). Web building, predatory brown with light tips, sternum yellow with slightly versatility, and the evolution of the Salticidae. In darker margin. Venter grey with central beige Shear W.A. (ed.), Spiders: Webs, Behavior and stripes. Pedipalps proximally and ventrally yellow, Evolution: 232-268. Stanford University Press, distally and dorsally dark-brown, fringed with Stanford. numerous light-grey, white and brown hairs, tarsi Jackson, RR (1986c). Communal jumping spiders with 2 retrolateral spines. Legs long and slender, (Araneae: Salticidae) from Kenya: interspecific nest proximally yellow, distally and dorsally darker, complexes, cohabitation with web-building spiders, metatarsi light-brown. First leg index below 5. and intraspecific interactions. New Zealand Joumal of Spines long, numerous on tibiae and metatarsi I Zoology 13: 13-26. and II. Jackson, R.R (1987). Comparative study of releaser Epigyne and internal genitalia presented in Figs pheromones associated with the silk of jumping spiders (Araneae, Salticidae). New Zealand Joumal of 10-11, similar to the genus Astia. Zoology 14: 1-10. Tibial and metatarsal spination: tI-II: pl-l-l-l-l­ Jackson, R.R. (1988). The biology of Jacksonoides (1), rl-l-l-l-l-(I); mI-II: pl-l-1-1, r1-1-1-1; tIll-IV: queenslandica, a jumping spider (Araneae: Salticidae) pO-0-0-0-1, rO-0-0-0-1; mIll-IV: pO-1-0-2, rO-1-0-2.