Icius nigricaudus

Icius nigricaudus
	A spider of the Icius genus
Scientific classification
Domain:	Eukaryota
Kingdom:	Animalia
Phylum:	Arthropoda
Subphylum:	Chelicerata
Class:	Arachnida
Order:	Araneae
Infraorder:	Araneomorphae
Family:	Salticidae
Subfamily:	Salticinae
Genus:	Icius
Species:	I. nigricaudus
Binomial name
	Icius nigricaudus; Wesołowska & Haddad, 2009

Icius nigricaudus is a

embolus, and hooked ibial apophysis, or appendage. The female has a simple epigyne

with long and narrow seminal ducts.

Taxonomy

Icius nigricaudus is a

clade Salticoida.^[5] Chrysillines, which had previously been termed heliophanines, are monophyletic.^[5] In 2016, Jerzy Prószyński split the genus from the Chrysillines into a group called Iciines, named after the genus. He stated the split was for practical reasons as Chrysillines had become unwieldy.^[6]

Description

Icius nigricaudus is a small slender spider. The male has a

embolus is straight and the tibial apophysis, or appendage, is hooked.^[3]

The female is similar in size and shape to the male.[7] The carapace is the same size and colour but lacks the spots of the male. The chelicerae are similar, but the labium is brown. The abdomen is the same size but the top is black with a white stripe down the middle and a narrow streak on the sides to the front. The underside is black with a yellow area visible and three small patches near the spinnerets. The legs and pedipalps are yellow.^[3] The epigyne has a slight indentation towards the front but is otherwise very simple. The copulatory openings lead to simple seminal ducts, which lead directly to the receptors,^[8]

The species can be differentiated from others in the genus by its copulatory organs. The male has a distinctive pedipalp and the female long and narrow seminal ducts. The female most closely resembles Icius dendryphantoides but can be identified by the elongated, rather than spherical, receptacles.^[3] The spider somewhat resembles ants of the Crematogaster genus in colour and size.^[9]

Distribution and habitat

Icius nigricaudus is endemic to South Africa.^[1] The holotype was discovered in 2005 in the Ndumo Game Reserve.^[3] The species is rare and lives on grasses found near to rivers and other wetlands and in the bark of Vachellia xanthophloea.^[9]