Nasoona Locket, 1982

Tanasevitch, Andrei V., 2014, New species and records of linyphiid spiders from Laos (Araneae, Linyphiidae), Zootaxa 3841 (1), pp. 67-89 : 78

Nasoona Locket, 1982

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

Gorbothorax Tanasevitch, 1998 new synonymy (type species Gorbothorax comatus Tanasevitch, 1998 , by original designation).

Remarks. The genus Gorbothorax Tanasevitch, 1998 was erected for five Nepalese erigonine species, based exclusively on males, with G. comatus Tanasevitch, 1998 as type species ( Tanasevitch 1998). A comparison of Gorbothorax representatives with species of the Southeast Asian genus Nasoona reveals a similar palp conformation, a similarly modified carapace, the same chaeto- and trichobothriotaxy, as well as a variegated body. The type species of both these genera are considered congeneric, thus, Gorbothorax Tanasevitch, 1998 becomes a junior subjective synonym of Nasoona Locket, 1982 n . syn. One of the characteristic features of Nasoona is the presence of an additional sclerite in the embolic division connected through a membranous tissue with the embolus, but lacking a duct (see Figs 33–35 ; 39–42). This sclerite seems to support and protect the embolus. A similar structure is found in species of numerous erigonine genera, e.g. Oedothorax Bertkau, 1883 , Gongylidioides Oi, 1960 , etc. Merrett (1963) termed this sclerite a “lamella”, putting it in quotation marks to emphasize its provisional designation, which would later be replaced by a special name. To designate this additional sclerite in the embolic division in Oedothorax, Tanasevitch (1998) proposed the term “convector”, which in Latin means “companion.” In addition to a convector, the embolic division in Nasoona has another additional sclerite, small, tightly adjoined to the distal part of the convector, which is to be named here as a paraconvector (see Figs 35, 41 ). Locket (1982), in his paper on West Malaysian linyphiids, designated this sclerite a “hinged lamella” while the convector was referred to as the “radical part of the embolus”. Both homology propositions seem to be incorrect. The sperm duct running from the suprategulum, through the loose membranous tissue of the column, to the embolic division misses the so-called “radical part” before entering the flagelliform embolus (see Figs 33, 34 ). This sclerite that does not have the sperm duct going through it is homologized here to the convector (“lamella”, in the sense of Merrett (1963); “radical part of the embolus” in the sense of Locket (1982)).

Species included. The genus comprises 12 species, including seven currently known in Nasoona (see Platnick 2014) and further five newly transferred from Gorbothorax : N. asocialis ( Wunderlich, 1974) n. comb., N. comata ( Tanasevitch, 1998) n. comb., N. conica ( Tanasevitch, 1998) n. comb., N. setifera ( Tanasevitch, 1998) , and N. wunderlichi (Brignoli, 1983) n. comb.

Distribution. Himalayas, Southeast Asia, Venezuela ( Platnick 2014).

Figures

FIGURES 33 – 43. Nasoona asocialis (Wunderlich, 1974) male specimen (from Pulau Tioman, West Malaysia, 33 – 38) and N. crucifera (Thorell, 1895) male specimen (from Tad Fan, Laos, 39 – 43). 33, 39, Embolic division, ectal, 42, mesal. 34, 40, Embolic division without paraconvector, ectal. 35, 41, Paraconvector, frontal. 36, 37, Palpal tibia, dorsal, different aspects. 38, 43, Distal suprategular apophysis, lateral.