wolf spider
- Also called:
- ground spider or hunting spider
wolf spider, (family Lycosidae), large family of more than 2,300 species and 135 genera of spiders named for their wolflike habit of chasing and pouncing upon prey. The group is widespread, with about 240 species occurring in North America and about 50 in Europe. Interestingly, numerous species occur north of the Arctic Circle and are important members of tundra ecosystems. Wolf spiders do not have a bite that is medically significant to humans.
- Kingdom: Animalia
- Phylum: Arthropoda
- Class: Arachnida
- Order: Araneae
- Infraorder: Araneomorphae
- Family: Lycosidae
See also list of arachnids.
Physical description
Most wolf spiders are typically dark brown and small to medium sized with a long and hairy body. Wolf spiders are noted for their running speed and have stout, long legs. They have excellent eyesight and are easily identified by the number and arrangement of their eight eyes: four small eyes in the lowest row, two very large eyes in a middle row, and two small or medium-sized eyes in a top row. The jaws are prominent and strong.
Natural history
Wolf spiders commonly occur in grass or under stones, logs, or leaf litter. They are especially active at night or if the sky is overcast. Most species build silk-lined tubular nests in the ground. Some conceal the entrance with rubbish; others build a turretlike structure above it. Many species are active hunters that roam in search of prey, though some wait at or near their burrow for passing prey. Only a few species spin webs.
Female wolf spiders are maternal and care for both their eggs and young. The eggs are contained in a gray silk sac that is attached to the female’s spinnerets, or silk-producing organs, so that she appears to be dragging a large ball. This adaptation is unique to wolf spiders. After hatching, the young spiderlings ride on the mother’s back for several days to weeks until they are large enough to survive on their own.
Major genera and species
Wolf spiders of the genus Pirata, often found near ponds or streams, have a V-shaped pale mark on the back. The abdomen often has chevronlike marks and paired yellow spots. Thin-legged wolf spiders (Pardosa), which have a lens-shaped greenish or gray egg sac, have relatively long legs with long spines on the “foot.” Burrowing wolf spiders (Geolycosa), which spend most of their lives in burrows, have heavy front legs that are used for digging.
The wolf spiders with the largest bodies are mostly of the genus Lycosa, a large group that includes L. tarentula of southern Europe (see tarantula). The snarling wolf spider (L. ringens) and the cunning wolf spider (Dolocosa dolosa), both endemic to Saint Helena, are listed as endangered species on the IUCN Red List of Threatened Species.
One of the largest wolf spiders, Hogna ingens, is found only on Deserta Grande in the Madeira Islands and is a critically endangered species. It has a body about 2.5 cm (1 inch) long and legs about the same length. Several related species, including the prowling wolf spider (H. nefasta), the Prosperous Bay plain wolf spider (H. cinica), and the inexorable wolf spider (H. inexorabilis) are also listed as endangered or critically endangered species.
