Catalogue of the smaller arachnid orders of the world

The Arachnida represent one of the most diverse and distinctive lineages of living animals. They first appeared during the Silurian and have persisted to the present day. Despite their longevity it is somewhat remarkable that only 13 extant orders are recognised. The majority of their diversity occurs within just two groups, Araneae and Acari, with nearly 38,000 (Platnick, 2000, 2003) and an estimated 48,200 (Halliday et al., 2000) named species, respectively. The remaining arachnid orders comprise just approximately 13% of the named fauna (Harvey, 2002a). Students of the Arachnida have been well served by the publication of several printed catalogues. The spider catalogues of Roewer (1942, 1954), Bonnet (1945–1961), Brignoli (1983) and Platnick (1989, 1993, 1997) have provided an inestimable service to araneologists, culminating in a unified web version (Platnick, 2002). The pseudoscorpions were catalogued by Harvey (1991) and the scorpions by Fet et al. (2000). The compilation of catalogues for the six smaller orders presented here only leaves uncatalogued the Opiliones and the three mite orders, Opilioacariformes, Acariformes and Parasitiformes.
The catalogue presented here provides full literature data on six orders, Amblypygi, Uropygi, Schizomida, Palpigradi, Ricinulei and Solifugae, and attempts to take into account the literature up to the end of 2001.