Afraflacilla


Afraflacilla is a genus of the spider family Salticidae. Most species are distributed in Eastern to Northern Africa and Australia, with two species found in Europe.
Spiders in this genus can produce sounds by rubbing a part of its leg against the head, using specialized structures, a process called stridulation. Some African species, both adults and juveniles, use their stridulatory organs for social communal behaviour.

''Afraflacilla'' in Australia

Afraflacilla species in Australia include A. grayorum, A. gunbar, A. ''huntorum, A. milledgei, A. stridulator, A. vestjensi and A. yeni. In Australia they occupy tree trunks in deserts, savanna woodland and in open sclerophyll forests from south west Western Australia to Cape York Queensland, mostly in warmer regions. There are many undescribed Australian species. Afraflacilla grayorum'' Grays' stridulating jumping spider, found in northern Australian deserts, was named in honour of Michael and Greta Gray.

Description

Afraflacilla are small to medium-sized spiders, ranging in body length from 3 to 6 mm.
The cephalothorax is rectangular with curved sides when viewed from above and low to very low from the side. A curved row of 12 or more stridulatory tubercles extends from below the anterior lateral eye to below the posterior lateral eye. These spiny tubercles correspond with opposing structures on the femur of the first leg.
Afraflacilla species have tubercles and bristles which they rub together to make sounds used in courtship and possibly defence. The line of small tubercles under the eyes on the side of the carapace are usually visible to the naked eye. The tubercles on the femur are rubbed against those on the side of the head to produce sound. Chelicerae are rather long, vertical, with two marginal teeth.
The abdomen is elliptical to elongate-ovate, somewhat squared-off at the front.
The first pair of legs is much larger than the others, sometimes huge and stout in comparison, sometimes very hairy and sometimes with a very large spur underneath the enlarged tibia.
The male palpal organ of many Australian Afraflacilla species has a large, circling embolus and retro-lateral tibial apophysis. Some undescribed Australian Afraflacilla species have greatly enlarged segments of the first pair of legs, and sometimes massive spurs coming from underneath the tibia and metatarsus. Enlarged leg-one segments are also a feature of Pseudicius, a genus widespread outside Australia.

Taxonomy

This genus was for a time included in the genus Pseudicius, and the boundaries between both genera are disputed. In 2016 Jerzy Prószyński erected the genus Psenuc for some borderline species. The name Afraflacilla is combined from Africa, where most earlier described species were found, and Flacilla Simon, 1901, an obsolete salticid genus now called Flacillula Strand, 1932. This genus name is in turn derived from Aelia Flaccilla, wife of Roman Emperor Theodosius I. Afraflacilla, Pseudicius, Festucula and Marchena are close relatives and form a monophyletic group.

Species

, this genus includes 51 species: