About Menemerus bivittatus (Dufour, 1831)
Gray wall jumpers of the species Menemerus bivittatus have a dorso-ventrally flattened body, covered in short, dense grayish-white hairs. Tufts of dark brown bristles grow near the species' large, forward-facing eyes. Adult spiders reach approximately nine millimetres in total length, with males being slightly smaller than females. Males have a blackish longitudinal dorsal stripe on the abdomen, with a brownish-white stripe on either side of this stripe. Their carapace and chelicerae are patterned black and white, and their legs carry transverse banding in the same black and white colours. Females are generally paler and more brown overall, with a larger carapace and abdomen than males. A female's carapace is edged with two black bands and one thin white stripe, while her abdomen has broad black stripes along each edge that join together at the posterior end. A female's legs are also banded, but their colouration is paler than that of a male's legs. Immature spiders look identical to adult females. Menemerus bivittatus is native to sub-Saharan Africa, where it occurs in countries including Senegal, Nigeria, Kenya, DR Congo, and South Africa. It has been widely introduced to other regions, and now holds a cosmopolitan distribution. In the Americas, this species is found in the US states of Florida, Texas, and California, and ranges south as far as Paraguay. It can also be found in several Caribbean islands, Colombia, and Venezuela. This spider is most often spotted on the outer surfaces of human-made structures.
