Evarcha seyun

Evarcha seyun is a small spider with a body divided into two main parts: cephalothorax and an abdomen. The male has a cephalothorax, that is between 2.2 and 2.3 mm (0.09 and 0.09 in) long and 1.6 and 1.7 mm (0.06 and 0.07 in) wide. The rounded carapace, the hard upper part of the cephalothorax, is dark brown with a darker rear and a lighter semi-lunar marking in the middle. The eye field is black with dense white hairs forming a light patch in the middle, in some examples dividing by two thin fawn lines, and fawn scales around some of the eyes themselves. In some examples, there are horns made of tufts of long dark hairs near the middle eyes. The underside of the cephalothorax, or sternum, is brownish. The spider's face, or clypeus, is yellowish-brown with a covering of white hairs. Its mouthparts, consisting of the chelicerae, labium and maxillae, are generally brown although there are whitish edges to the tips of the maxillae, which also have a covering of dark hairs. The male spider's abdomen narrower than the carapace. It measures between 2.0 and 2.3 mm (0.08 and 0.09 in) in length and has a width of between 1.3 and 1.5 mm (0.05 and 0.06 in). The top is generally dark brown with a white area to the front and a wide white band extending near to the end. The underside is yellow marked with a large dark grey triangular patch. …

Evarcha spiders live across the world, although those found in North America may be accidental migrants. Evarcha seyun is endemic to the Arabian Peninsula and lives in the United Arab Emirates and Yemen. The holotype was discovered in 2002 in Yemen near Seyun, the area after which it is named. The spider has been observed living in the Al Mahrah and Hadramaut Governorates. The first examples identified in the United Arab Emirates were initially found on Jebel Hafeet in 2003. It was subsequently seen at different locations across the Emirates of Ajman and Sharjah. For example, multiple examples were found in Wadi Shawka in 2006 and another female in Wadi Bih in 2008. In 2010, the species was first found in the Emirate of Umm Al Quwain, The first example to be identified in the Emirate of Abu Dhabi was first discovered in 2013 living in the Al Wathba Wetland Reserve. It has been designated as being common across the country.