Taxonomy

Cocalus, with four species in the Oriental and Australian Regions, has one Australian species: Cocalus gibbosus. Other genera belonging to the same Old World group with Australian representatives include Cyrba, Mintonia and Portia (Maddison 2015). Further information on the genus and described species can be found in Richardson and Żabka (2017).

Description

Cocalus spp. are medium-sized, robustly-built spiders, ranging in body length from 7 to 9 mm with a high cephalothorax and a long abdomen. The upper surface of the carapace has prominent humps supporting the eyes on each side and also one on the mid-line immediately behind the anterior eyes. There is an orange fringe on the anterior edge of the cephalothorax and an orange patch on the front of the upper surface of the abdomen. The chelicerae have four retromarginal teeth (plurident) with three or more teeth on the promargin. The legs are long and strongly-built.

The male has a talon-shaped embolus on the distal edge of the tegulum, which is round and without a proximal lobe. The tibia has a truncated ventral apophysis and a wide-based, bizarrely-shaped retro-lateral tibial apophysis.

The female has a single epigynal atrium a little way from the epigastric fold with two very large spermathecae mostly anterior to it but also extending posteriorly to the epigastric fold. There is a large median pocket in the epigastric fold.

Biology

Cocalus gibbosus is found on foliage in rainforest. It hunts spiders.

Distribution

Cocalus gibbosus is known from only a few locations in north-eastern Queensland.

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.

Jackson, R.R. 1990. Predatory and nesting behaviour of Coccalus gibbosus a Spartaeinae jumping spider (Araneae, Salticidae) from Queensland. New Zealand Journal of Zoology 17, 483-490.

Richardson, B.J. & Żabka, M. 2017. Salticidae. Arachnida: Araneomorphae. Canberra, Australian Faunal Directory. Australian Biological Resources Study, at https://biodiversity.org.au/afd/taxa/SALTICIDAE.

Wanless, F.R. 1981. A revision of the spider genus Cocalus (Araneae: Salticidae). Bulletin of the British Museum (Natural History) Zoology 41, 253-261.

* The information sheet should be interpreted 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.