Portia is a genus of jumping spider that feeds on other spiders (i.e., they are araneophagic or arachnophagic). They are remarkable for their intelligent hunting behaviour, which suggests that they are capable of learning and problem solving, traits normally attributed to much larger animals. Taxonomy and evolution The genus was established in 1878 by German arachnologist Friedrich Karsch. The fringed jumping spider (Portia fimbriata) is the type species. Molecular phylogeny, a technique that compares the DNA of organisms to construct the tree of life, indicates that Portia is a member of a basal clade (i.e. quite similar to the ancestors of all jumping spiders), and that the Spartaeus, Phaeacius, and Holcolaetis genera are its closest relatives. Wanless divided the genus Portia into two species groups: the schultzi group, in which males' palps have a fixed tibial apophysis; and the kenti group, in which the apophysis of each palp in the males has a joint separated by a membrane. The schultzi group includes P. schultzi, P. africana, P. fimbriata, and P. labiata. At least some species of Portia are in the state of reproductive isolation: in a laboratory, male P. africana copulated with female P. labiata but no eggs were laid; during all cases the female P. labiata twisted and lunged in an attempt to bite. Some specimens found trapped in Oligocene amber were identified as related to Portia. Distribution and ecology The 17 described species are found in Africa, Australia, China, Madagascar, Malaysia, Myanmar, Nepal, India, the Philippines, Sri Lanka, Taiwan, and Vietnam. Portia are vulnerable to larger predators such as birds and frogs, which a Portia often cannot identify because of the predator's size. Some insects prey on Portia, for example, mantises, the assassin bugs Nagusta sp. indet. and Scipinnia repax. Appearance Portia are relatively small spiders. For example, adult females of Portia africana are in body length and adult males are long. Intelligence Portia often hunt in ways that seem intelligent. All members of Portia have instinctive hunting tactics for their most common prey, but can improvise by trial and error against unfamiliar prey or in unfamiliar situations, and then remember the new approach. They are capable of trying out a behavior to obtain feedback regarding success or failure, and they can plan ahead (as it seems from their detouring behavior). Portia species can make detours to find the best attack angle against dangerous prey, even when the