Platnick (2013) lists 528 species in the spider family Dysderidae (woodlouse spiders). Dysderids are native to the western Palearctic, with most species being circum-Mediterranean, many of them with narrow distributions (Cook 1965a,b; Ubick 2005). Just one of these species, Dysdera crocata, is found in North America north of Mexico (and it is not native; this synanthropic species has been spread widely around the world) (Ubick 2005; Bradley 2013).
Dysderids have six eyes, two in front and four behind, with the posterior row slightly procurved (i.e., the lateral eyes are anterior to the median eyes). There are two pairs of conspicuous spiracles under the abdomen. Dysderids have huge chelicerae and long fangs, giving them a fearsome appearance, but none of the scattered reports of humans being bitten by dysderids have been medically serious. These bites have sometimes resulted from the spider building its retreat in the fingers of a glove. (Bradley 2013)
Dysderids are widely believed to feed mainly on terrestrial isopods (woodlice, pillbugs). Although it is unclear how specialized dysderids are in nature (they will take a range of prey in captivity), some dysderid species are known to feed on isopods in the wild and their modified chelicerae and feeding behavior appear clearly to indicate at least some degree of specialization for capturing these prey and biting through their hard calcareous exoskeletons (Cooke 1965a,b; Pollard et al. 1995; Řezáč and Pekár 2007 and references therein; Řezáč et al. 2008).
Dysderids are nocturnal wandering hunters. They are ground dwellers, often found under rocks and logs in both grasslands and forests. Cooke (1965a,b) studied the life history of two British Dysdera species, D. crocata and D. erythrina. These spiders build retreats for molting and depositing eggs, which are loosely bound with silk and guarded by the female within a thick cocoon in which she seals herself. In captivity, these spiders reach sexual maturity in around 18 months and then live for an additional two to three years. In the Nearctic region, the introduced Dysdera crocata is found mainly in urban areas and disturbed habitats. (Cooke 1965a; Ubick 2005)
- Bradley, R.A. 2013. Common Spiders of North America. University of California Press, Berkeley.
- Cooke, J.A.L. 1965a. Spider genus Dysdera (Araneae, Dysderidae). Nature 205: 1027-1028.
- Cooke, J.A.L. 1965b. A contribution to the biolog of the British spiders belonging to the genus Dysdera. Oikos 16: 20-25.
- Pollard, S.D., R.R. Jackson, A. Vanolphen, and M.W. Robertson. 1995. Does Dysdera crocata (Araneae: Dysderidae) prefer woodlice as prey? Ethology, Ecology and Evolution 7(3): 271-275.
- Řezáč, M. and S. Pekár. 2007. Evidence for woodlice-specialization in Dysdera spiders: behavioural versus developmental approaches. Physiological Entomology 32: 367-371.
- Řezáč, M., S. Pekár, and Y. Lubin. 2008. How oniscophagous spiders overcome woodlouse armour. Journal of Zoology 275: 64-71.
- Ubick, D.. 2005. Dysderidae. P. 103 in D. Ubick, P. Paquin, P.E. Cushing, and V. Roth (eds.) Spiders of North America: an Identification Manual. American Arachnological Society.
Molecular Biology and Genetics
Statistics of barcoding coverage
|Specimen Records:||469||Public Records:||362|
|Specimens with Sequences:||398||Public Species:||72|
|Specimens with Barcodes:||285||Public BINs:||82|
|Species With Barcodes:||38|
The family Dysderidae (woodlouse hunters, sowbug-eating spiders or cell spiders) are araneomorph spiders found primarily in Eurasia, although extending into North Africa, with very few species occurring in South America, and one (Dysdera crocata) introduced into many regions of the world.
Dysderids have six eyes, and are haplogyne, i.e. the females lack a sclerotized epigyne. There is a substantial number of genera, but two of them, Dysdera and Harpactea, account for a very large number of the species and are widespread across the family's range. One species, Dysdera crocata (the woodlouse hunter), has been transported over much of the planet together with its preferred foods - woodlice. Dysdera also feeds on beetles. These spiders have very large chelicerae, which they use to pierce the armored bodies of woodlice and beetles. There are also some reports that they have a mildly toxic venom that can cause local reactions in humans; with their huge fangs there is little doubt that they could bite if threatened, but the venom has not been well studied. Most give a threat display before attacking, and the bite is less painful than a bee sting.
The spiders have their six eyes arranged in a semicircle like segestrids, but have only the first two pairs of legs produced forward. Dysdera crocata has a characteristic coloring, which can only be confused with spiders in the corinnid genera Trachelas and Meriola: the carapace is dull red-brown and the abdomen gray or tan. The "two-tone" look, with the abdomen much lighter than the cephalothorax, is quite striking.
These rather large, burly-looking, slow-moving spiders are often seen in the autumn in basements and other cool areas of homes; presumably they are looking for a winter shelter.
The categorization into subfamilies follows Joel Hallan's Biology Catalog.
- Dysderinae C. L. Koch, 1837
- Cryptoparachtes Dunin, 1992 (Georgia, Azerbaijan)
- Dysdera Latreille, 1804 (worldwide)
- Dysderella Dunin, 1992 (Azerbaijan, Turkmenistan))
- Dysderocrates Deeleman-Reinhold & Deeleman, 1988 (Balkans)
- Harpactocrates Simon, 1914 (Europe)
- Hygrocrates Deeleman-Reinhold, 1988 (Georgia, Turkey)
- Parachtes Alicata, 1964 (Southern Europe)
- Rhodera Deeleman-Reinhold, 1989 (Crete)
- Stalitochara Simon, 1913 (Algeria)
- Tedia Simon, 1882 (Israel, Syria)
- Dasumia Thorell, 1875 (Europe, Middle East)
- Folkia Kratochvíl, 1970 (Balkans)
- Harpactea Bristowe, 1939 (Europe to Iran, Mediterranean)
- Holissus Simon, 1882 (Corsica)
- Kaemis Deeleman-Reinhold, 1993 (Italy)
- Minotauria Kulczyn'ski, 1903 (Crete)
- Sardostalita Gasparo, 1999 (Sardinia)
- Stalagtia Kratochvíl, 1970 (Balkans, Greece)
- Thereola petiolata (Koch & Berendt, 1854) †
- Platnick, Norman I. (2008): The world spider catalog, version 8.5. American Museum of Natural History.