Nasoona Locket, 1982

Tanasevitch, Andrei V., 2018, A survey of the genus Nasoona Locket, 1982 with the description of six new species (Araneae, Linyphiidae), Revue suisse de Zoologie 125 (1), pp. 87-100 : 88

Genus Nasoona Locket, 1982

Type species: Nasoona prominula Locket, 1982 by original designation.

Taxonomic remarks: The genus includes mediumsized erigonines with a variegated abdomen and, in most cases, with a postocular elevation on the male carapace bearing a group of curved, spines, stout spines or setae.

Three species lack this carapace elevation: N. asocialis ( Wunderlich, 1974) , N. chrysanthusi Locket, 1982 and a new species described below.

The chaetotaxy formula is 2.2.1.1. Two exceptions given in the literature, 1.1. 1.1 in N. coronata ( Simon, 1894) and 1.1. 1.1 in the male of N. locketi Millidge, 1995 , are mistakes based on incomplete spination caused by partial loss of spines. Each metatarsus is with a trichobothrium, except for N. coronata .

The male palp is characterized by the following features: 1) highly modified palpal tibia;

2) poorly expressed distal suprategular apophysis;

3) reduction of median membrane and radix;

4) presence of convector (see Tanasevitch 1998, 2014); 5) presence of an additional sclerite in embolic division, named paraconvector (see Tanasevitch, 2014). At present the paraconvector is only known in Nasoona , but most probably this sclerite is more widely present among the Erigoninae. The embolus division of many taxa in this group is still poorly investigated.

The epigyne in Nasoona is typical for many erigonines and represented mostly by a shallow epigynal cavity which is sometimes divided by a septum and in a few species partially covered from above by an overhanging, visorlike outgrowth of the anterior epigynal wall. Receptacles are relatively small, subspherical or beanlike.

The position of the genus within the Erigoninae is unclear, but some somatic characters, i.e. chaeto- and trichobothriotaxy, modified male carapace, as well as genitalia conformation show similarity with Gongylidioides Oi, 1960 and in part Oedothorax .

Species included: Excluding one species which is removed from Nasoona , the genus currently comprises 17 species, 6 of them are described as new below.

Distribution: Extreme south of the Palaearctic Region: Nepal Himalayas and southern China; throughout the Oriental Region; Neotropical Region: Venezuela.

Range: Disjunct Oriental-Neotropical.