Long-Spinnered Ground Spiders
Prodidomidae Simon, 1884
(compiled by Barbara Baehr)
Identification
The Long-Spinneret Ground Spiders belong to the superfamily Gnaphosoidea. The greatly elongated base of the piriform gland spigots easily identifies them. Their bodies or at least parts thereof are covered with shiny recumbent scales or plumose setae (Platnick, 1990). In Australia, the Long-Spinneret Ground Spiders consist of two subfamilies, the Prodidominae and the Molycriinae. The Prodidominae are quite small (1.8-4.3 mm), flat, pale spiders with laterigrade legs and greatly enlarged, canoe-shaped posterior lateral spinnerets. Most of the species and genera belong to the Molycriinae. These small, to medium sized (1.8mm - 5.0mm) spiders vary in colouration and can be pale, cinnamon or greyish. They can be easily identified by their extremely long anterior lateral spinnerets, which are situated anteriorly and far removed from the other spinnerets. In all prodidomids, the posterior median eyes are flat, silvery and triangular, egg-shaped or irregularly rectangular. The Molycriiane have both eye rows strongly procurved, whereas in the Prodidominae the anterior eye row is straight.
Biology
In Australia, the distribution of Long-spinneret Ground Spiders covers the whole mainland and Tasmania. They live in nearly every habitat, from rainforests in Queensland to the dry deserts of the Kimberleys in Western Australia. Little is known about their biology. Prodidomidae are ground dwellers. Most of them are nocturnal, hiding in the litter at daytime, however, the small species of the genus Myandra seem to be active during the day. Their colouration – with horizontal stripes on the abdomen - and their behaviour suggest that they are mimicking ants.
Prodidomidae in Australasia
Australia
In 1990 Norman Platnick redefined the family Prodidomidae including now only those gnaphosoid spiders with greatly elongated piriform gland spigot bases accompanied by highly plumose or scaled setae. The Prodidomidae are an excellent example of the extraordinarily diverse Fauna of Australia. A recent revision of this family in the Australasia recognised 137 species in seven genera although only ten species were previously known from the region (Platnick and Baehr, 2006):
The genus Prodidomus contains eight species. Seven species are newly described from Western Australia, the Northern Territory, and Queensland. In the genus Molycria only the widespread species Molycria mammosa (O. P.-Cambridge) and Molycria quadricauda (Simon) were already described, 34 species are new. The new genus Wydundra is described for 40 new Australian species. Molycria splendida Simon is transferred to the new genus Wesmaldra, and 13 new species of Wesmaldra are described from Western Australia and the Northern Territory. Molycria flavipes Simon is transferred to the new genus Nomindra and 15 new species of Nomindra are described. The male of Cryptoerithus occultus Rainbow is described for the first time, and 18 new species are assigned to Cryptoerithus. Adult males and females of Myandra cambridgei Simon and Myandra bicincta Simon are described for the first time, as are two new species of Myandra.
New Zealand
No species of Prodidomidae are listed from New Zealand according to Norm Platnick`s (The World Spider Catalogue).
South East Asia
Long-Spinneret Ground Spiders appear to be very rare in South East Asia and only single female specimens have been found in the genera Prodida (Philippines), Prdidomus (Myanmar), and Zimiris (possibly Java) (Murphy and Murphy 2000, Plattnick and Penney 2004)
References
Murphy, F. and Murphy, J. 2000. An Introduction to the Spiders of South East Asia. Malaysian Nature Society, United Selangor Press Sdn. Bhd.
Platnick, N.I. 1990. Spinneret morphology and the phylogeny of ground spiders (Araneae, Gnaphosoidea). American Museum Novitates 2978: 1-42.
Platnick, N.I. and Baehr, B.C. 2006. A revision of the Australasian ground spiders of the family Prodidomidae (Araneae, Gnaphosoidea). Bulletin of the American Museum of Natural History 298: 1-287.
Platnick, N.I. and Penny, D. (2004). A Revision of the widespread spider genus Zimiris (Araneae, Prodidomidae). American Museum Novitates 3450: 1-12.