Taxonomy

Judalana has one Australian species, Judalana lutea. In Australia the genus is related to other ant-mimicking genera Damoetas, Ligonipes, Myrmarachne and Rhombonotus, and elsewhere to Belippo (Africa) and Bocus (Borneo and the Philippines) (Maddison, 2015). Judalana, along with Rhombonotus and Ligonipes, has a strong, thick fringe of black hairs on the tibia of the first leg.  Further information on the genus and described species can be found in Richardson and Żabka (2017) and Whyte and Anderson (2017).

Description

Judalana lutea is a small to medium-sized spider, body length 3 to 5 mm. Like related genera it is an ant mimic.  The cephalothorax is elongate, narrowing after the posterior lateral eyes. The male has a narrow abdomen with a distinct anterior hump and a constriction a third of the way along. The abdomen has a two-toned appearance with the anterior third being yellow or orange and the posterior section black mimicking Opisthopsis (Strobe) ants, notably Opisthopsis rufithorax. In the females, the abdomen is fatter and orange with a small darker section at the posterior end.  The male paturon has a projection on the anterio-medial surface not found in the very similar Rhombonotus.

Chelicerae in males are strongly geniculate and have four retromarginal teeth (plurident). There is a distinctive small hornlike process (mastidion) projecting from the front of each paturon. In the female there are three fused retromarginal teeth and no mastidion. The first pair of legs is much stronger than the others, mainly orange in colour. Black tibia have a brush of flattened black hairs in both sexes.

The male’s palp has a sharp, retro-lateral tibial apophysis of medium length bending towards the ventral side. The tegulum is round, with a proximal lobe. The embolus is long, roughly forming a circle around the tegulum. The tip of the embolus is bifurcated.

The female’s epigynal copulatory openings are on the posterior median edges of two clearly defined atria. The insemination ducts, spermathecae and fertilisation ducts form a pair of tubes varying little in diameter. The spermathecae are not easily seen, but are beyond the lateral edges of the atria. The fertilisation ducts follow a coiled path before moving anteriorly between the atria.

Biology

Judalana lutea is a cryptic spider found on tree foliage where it hides in a folded leaf. It is a mimic of the ant Opisthopsis rufithorax.

Distribution

Judalana lutea is found in high rainfall areas from northern Queensland to mid New South Wales.

References

Maddison, W.P. 2015. A phylogenetic classification of jumping spiders (Araneae: Salticidae). Journal of Arachnology 43, 231-292.

Rix, M.G. 1999. A new genus and species of ant-mimicking jumping spider (Araneae: Salticidae) from southeast Queensland, with notes on its biology. Memoirs of the Queensland Museum 43, 827-832.

Richardson, B.J. & Żabka , M. 2016. Salticidae. Arachnida: Araneomorphae. Canberra, Australian Faunal Directory. Australian Biological Resources Study, at https://biodiversity.org.au/afd/taxa/SALTICIDAE.

Whyte, R. & Anderson, G. 2017. A Field Guide to Spiders of Australia. CSIRO Publishing: Clayton.

* 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.