Eresus

Eresus is a genus of spiders in the family Eresidae, commonly known as velvet spiders or ladybird spiders. The genus includes several species found in Europe, North Africa, the Middle East, and parts of Asia. Members are often noted for their striking coloration in some species, which has contributed to their common name.

Adults show marked sexual dimorphism. Females are typically robust and dark, with a distinctive red or orange patch on the dorsal abdomen. Males are more slender and may have brighter coloration on the abdomen and legs. Juveniles can vary in color but often resemble the female pattern before maturing.

Habitats are usually dry, open environments such as grasslands, scrublands, and rocky areas. They are ground-dwellers that hide in silk-lined retreats under stones, in crevices, or within leaf litter. They do not spin large webs; instead they rely on ambush hunting of small arthropods and quick movements to capture prey.

Behavior and reproduction: Eresus species are largely solitary outside of mating. Mating involves courtship signals, and the female lays eggs in a silk cocoon after fertilization. The genus produces venom to subdue prey, and while bites can occur, they are rare and not considered dangerous to humans.

Taxonomy and conservation: The genus was first described by Walckenaer in 1805. Some Eresus species have experienced habitat loss or fragmentation, making certain populations of conservation concern in parts of their range. Protective measures exist for select European species in protected areas.