Chalcoscirtus picinus

Chalcoscirtus picinus is a small spider that is typical for the genus, both in size and in the lack of patterns on its body. It has a body that consists of a cephalothorax and an abdomen that is typical in shape and colouration for the genus. The female has a cephalothorax that is typically 1.4 mm (0.06 in) long and 1 mm (0.04 in) wide. The carapace, the hard top of the cephalothorax, is a greyish-brown flattened oval. The eye field is black with a blue metallic lustre and long brown bristles near the eyes themselves. The spider's face, or clypeus, is very low. The spider's mouthparts, including the chelicerae, labium and maxilae, are brownish-black. The chelicerae are low with a few long bristles visible on the outside. There are two teeth at the front and none at the back. The abdomen is a slightly swollen oval that is blackish-grey and covered in fine brown hairs. It is typically 2 mm (0.08 in) long and 1.5 mm (0.06 in) wide. The spider's spinnerets are dark its legs are whitish-yellow with brown hairs and dark brown spines.^[5]

The spider has distinctive copulatory organs that help identify the species. The female has a small epigyne with a very small oval membrane forming a window in the centre. It is this window that helps distinguish the spider from others in the genus, mainly as is smaller and narrower than in other species. The copulatory openings lead to very short insemination ducts, initially marked with very small levels of sclerotisation. The receptacles, or spermathecae, are bean-shaped. The spider has large accessory glands.^[10] The male has not been described.^[1]

Chalcoscirtus species are found across Europe and Asia, and even as far as North America. They seem to particularly thrive in montane ecosystems, especially those with Alpine or Mediterranean climates.^[11] Some live on the Arabian Peninsula, including Chalcoscirtus picinus, which is endemic to the United Arab Emirates.^[1][12] The female holotype was found in Wadi Bih in 2010.^[13]