Six-spotted fishing spider

Description

Dolomedes triton is an arachnid from the nursery web spider family Pisauridae. This species is from the genus Dolomedes, or the fishing spiders. Found in wetland habitats throughout North America, these spiders are usually seen scampering along the surface of ponds and other bodies of water. They are also referred to as dock spiders because they can sometimes be witnessed quickly vanishing through the cracks of boat docks. D. triton gets its scientific name from the Greek mythological god Triton, who is the messenger of the big sea and the son of Poseidon. This spider can be identified by its large size and distinctive markings. It has eight eyes with good vision, and its body is grey to brown. They have a white to a pale cream colored stripe running down each side of the cephalothorax. The abdomen has many light colored spots and also has light colored lines running down the sides of the abdomen. When this species is seen from below, there are six dark spots present on the bottom of the cephalothorax, hence its common name. Like many spiders, this species shows sexual dimorphism. The female is larger than the male. The female is about 60 millimeters (2.4 in) long including the legs; her body length is 15–20 mm (0.59–0.79 in) and the male's body is 9–13 mm (0.35–0.51 in) long. The juvenile spiders look similar to adults but are smaller. The juvenile goes through a series of molts within their lifetime to grow and reach adult size. While somewhat visually similar to D. striatus, this species is distinguished by its unique pattern of three pairs of dark sternal spots and several light spots on the abdominal dorsum. Males have a more apically rounded tibial apophysis that extends past the tibia apex. In females, the seminal valve of the copulatory apparatus can be found in the anterior half of the dorsal epigynous area with loose fertilization tubes. This species is known to be remarkably variable over their geographic range, both in terms of appearance and behavior.