Pararchaeidae Forster & Platnick, 1984
(compiled by Michael G. Rix, with photographs by the author)
Pararchaeid spiders share a number of characters that readily separate them from all other spiders. They are small to very small in size (less than 3mm in body length), and variously brown, yellow or cream in colour. They possess a distinctly raised and clearly demarcated pars cephalica (head region) bearing eight eyes and relatively few hairs. The chelicerae are elongate, and project out of an oval foramen in the front of the cephalothorax; this foramen is completely surrounded by sclerotised cuticle. The chelicerae are constricted proximally, with peg teeth next to the fangs. The carapace cuticle is squamate (scaled), the legs are relatively short, and the tarsi are distinctly longer than the metatarsi. The abdomen is oval in profile, with four dorsal sigilla (muscle attachment points) forming a quadrangle, and six spinnerets. The male pedipalp possesses a prominent retrolateral paracymbium, and the female genitalia are entelegyne, with globular receptacula. The unique combination of a fully sclerotised cephalothoracic foramen plus entelegyne female genitalia separates the Pararchaeidae from all other families.
Pararchaeid spiders are known only from the forests of Australia and New Zealand, where they live within moss, thick leaf litter or under rotting logs. Some species are also arboreal, living under tree bark or among dense foliage. Most species are rare or very rare in nature, and many taxa are restricted in distribution. Egg sacs are attached to the undersides of stones or logs, and are remarkable in being several times larger than the female spiders that build them (see photograph).
Pararchaeidae in Australasia
Thirty-four pararchaeid species in seven genera have now been described from Australasia, after Rix (2006) revised the family. Of these, most species are from the Australian mainland, with only three species in New Zealand.
Thirty-one pararchaeid species in five genera are described from Australia. These species are listed below:
- A. corticola (Hickman, 1969) (TAS)
- A. falcata Rix, 2006 (NSW)
- A. raveni Rix, 2006 (QLD)
- A. robusta (Rix, 2005) (TAS)
- F. anzac Rix, 2006 (QLD)
- F. badja Rix, 2006 (NSW)
- F. barmah Rix, 2006 (NSW, VIC)
- F. hickmani (Rix, 2005) (TAS)
- F. lofty Rix, 2006 (SA)
- F. lulu Rix, 2005) (TAS)
- F. stirlingensis Rix, 2006 (WA)
- N. binnaburra (Forster, 1955) (QLD)
- N. bryophila (Hickman, 1969) (NSW, VIC, TAS)
- O. bodalla Rix, 2006 (NSW)
- O. bondi Rix, 2006 (NSW)
- O. daviesae Rix, 2006 (QLD)
- O. harveyi Rix, 2006 (WA)
- O. janineae Rix, 2006 (NSW)
- O. ornata (Hickman, 1969) (TAS)
- O. platnicki Rix, 2006 (QLD)
- O. saxicola (Hickman, 1969) (TAS)
- O. spurgeon Rix, 2006 (QLD)
- O. stradbroke Rix, 2006 (QLD)
- O. valida Rix, 2006 (NSW)
- O. waldockae Rix, 2006 (WA)
- O. werrikimbe Rix, 2006 (NSW)
- O. westraliensis Rix, 2006 (WA)
- O. wiangarie Rix, 2006 (NSW)
- W. pusilla Rix, 2006 (WA)
- W. sinuosa Rix, 2006 (WA)
- W. spinosa Rix, 2006 (WA)
Three pararchaeid species in three genera are described from New Zealand:
- F. rubra (Forster, 1949)
- O. forsteri Rix, 2006
- P. alba Forster, 1955
Pararchaeid spiders are not known from South-east Asia.
Forster, R. R. (1949). New Zealand spiders of the family Archaeidae. Records of the Canterbury Museum 5: 193-203.
Forster, R. R. (1955). Spiders of the family Archaeidae from Australia and New Zealand. Transactions of the Royal Society of New Zealand 83: 391-403.
Forster, R. R. and Platnick, N. I. (1984). A review of the archaeid spiders and their relatives, with notes on the limits of the superfamily Palpimanoidea (Arachnida, Araneae). Bulletin of the American Museum of Natural History 178: 1-106.
Hickman, V. V. (1969). New species of Toxopidae and Archaeidae (Araneida). Papers and Proceedings of the Royal Society of Tasmania 103: 1-11.
Rix, M. G. (2005). A review of the Tasmanian species of Pararchaeidae and Holarchaeidae (Arachnida, Araneae). The Journal of Arachnology 33: 135-152.
Rix, M. G. (2006). Systematics of the Australasian spider family Pararchaeidae (Arachnida: Araneae). Invertebrate Systematics 20: 203-254.