Evarcha picta

Evarcha picta is a small, light-coloured spider with looks that are typical for the genus. The spider's body is divided into two main parts: a round cephalothorax and an oval abdomen. The male has a carapace, the hard upper part of the cephalothorax, that is typically 2.6 mm (0.10 in) long and 2.1 mm (0.08 in) wide. It is rather high, yellow with brown sides and has a covering of brown and greyish hairs. There is a distinctive fovea, or indentation, in the centre of the carapace, that is the centre of a series of dark lines that radiate to the rearmost edge. It has a darker eye field with long bristles around the eyes themselves. There are distinctive white patches and orange hairs around the front eyes. The underside of the cephalothorax, or sternum, is yellow. The spider's face, or clypeus, is low and brownish-orange with a covering of brownish-orange hairs. Its mouthparts are distinctive. The chelicerae are light brown with two teeth to the front and one to the back. The labium and maxillae are generally yellow, although the base of the labium is slightly darker than the rest.^[4]

The male spider's abdomen is narrower than its carapace. It measures typically 2.4 mm (0.09 in) in length and having a width of between 1.7 mm (0.07 in) The top is generally yellow with a brown pattern, and covered in brown and yellow hairs that are longer to the front.^[4] It is generally lighter to the front than the back, with two white spots flanking a succession of tessellating white chevrons to the rear.^[13] The underside is yellow with a pattern of a three lines down the middle from the front to back, the middle line being thicker than the others. The spider has yellow spinnerets. Its legs are brown and yellow with brown hairs and spines. The pedipalps are brownish and hairy.^[4]

The male spider has distinctive copulatory organs. It has a rhomboid palpal bulb, with a large bulbous protrusion at its base and rounded sides. The embolus is accompanied by a spike, or terminal apophysis, that makes it look as it has two branches. They are joined by a membrane.^[4] There are small hairs on the cymbium and longer hairs on the palpal tibia. The tibia has a wide protrusion, or tibial apophysis, that also has a small tooth on its side near its end.^[13]

The female is smaller than the male, with an abdomen generally 2 mm (0.08 in) long and 1.6 mm (0.06 in) wide, and a carapace 2.4 mm (0.09 in) long and 1.9 mm (0.07 in) wide. It looks like the male but the pattern on the abdomen is less clear. It is generally more yellow and the white spots are less clear. The legs are completely yellow. The copulatory organs are again distinctive. The spider has a large wide shallow depression in the middle of its epigyne and two pockets to the rear near the epigastric furrow, a line near the very rear of the spider. The copulatory openings are mounted to the back and lead to very large many-chambered spermathecae, or receptacles, that consist of a single loop. They have heavy sclerotisation.^[4] The insemination ducts are narrow and lead to long accessory glands as well as the spermathecae.^[13][14]

The spider is hard to distinguish from other Evarcha spiders that are found in Africa. It is particularly similar to the related Evarcha culicivora. Externally, it most easily distinguished by its clypeus, which is brownish-orange compared to the red of the other spider. The copulatory organs are also different. The female Evarcha picta has a wider depression in the centre of the epigyne, narrower insemination ducts, longer accessory glands and smaller spermathecae, while the male has a shorter embolus.^[4] The higher level of sclerotisation on the female epigyne and the wider male tibial apophysis similar differentiate the spider from the similar Evarcha prosimilis.^[15]

Evarcha spiders live across the world, although those found in North America may be accidental migrants.^[16] Evarcha picta is endemic to Yemen.^[1] It has only been seen living in the Dhamar Governorate.^[17] The holotype was discovered in 1998 near Hammam 'Ali. Other examples were found locally.^[4]