Yuelushannus gen. nov. (Araneae, Linyphiidae) from China

The new erigoninae genus Yuelushannus gen. nov. with two new species, Y. alatus sp. nov. (♂♀) and Y. barbatus sp. nov. (♂♀), are described from Hunan and Hubei Provinces. Detailed descriptions of somatic features and genitalic characters, photos of the habitus and copulatory organs, line drawings of copulatory organs and a distribution map are provided.


Introduction
The spider family Linyphiidae Blackwall, 1859 comprises 10% of all spiders, making it the second largest family with 4,613 species belonging to 613 genera worldwide (World Spider Catalog 2019). Li & Lin (2016) listed 371 linyphiid species in 154 genera from China, including 74 species in 42 genera from Hubei and Hunan Provinces, out of which 172 species in 91 genera belong to the subfamily Erigoninae. While examining specimens collected from Hunan and Hubei Provinces, two new species belonging to an unknown genus were found. Yuelushannus gen. nov. and its new species are described. The type specimens are deposited in the College of Life Sciences, Hunan Normal University, Changsha, China.

Material and Methods
Specimens were collected by sieving leaf litter and were kept in 75% ethanol. After dissecting from the body, epigynes were cleared in trypsin solution before examination and photography. Left male palps were used for descriptions and illustrations. Specimens were examined and measured with a Leica M205C stereo microscope. Photos were taken with a digital camera (Canon PowerShot G12) mounted on an Olympus BX53 and with a Leica MC170 HD camera mounted on a Leica M205C, and stacked using Helicon Focus software (3.10). Maps were created in ArcMap 10.2 and then modifi ed by using Adobe Photoshop CS2 Extended (Fig. 11). Leg measurements are given in the following order: total length (femur, patella + tibia, metatarsus, tarsus). All measurements are given in millimeters (mm). The terminology used in text and fi gure legends follows Hormiga (2000) and Zhao & Li (2014).

AER
= anterior eye row ALE = anterior lateral eyes alt.
= altitude AME = anterior median eyes AME-ALE = distance between AME and ALE AME-AME = distance between AME ARP = anterior radical process

Etymology
The genus is named after the type locality (Yuelu) of the type species. Gender masculine.

Diagnosis
Male abdomen with two pairs of sigellae and distinct scutum at anterior two third. (

Natural History
Mainly lives under leaf litter layer of broad-leaved and shrubbery forest; breeding season from October through April; adapted to temperatures from 0°C to 39°C.

Etymology
The species name comes from Latin adjective "alatus", meaning "winged" and refers to the ocular region with wing-like spines in the male.

Diagnosis
This new species resembles Yuelushannus barbatus sp. nov. as two-thirds of the male abdomen has a very distinct scutum, the cephalic lobe and pits are distinct, both male and female abdomen with four sigillae. Tibial apophyses densely covered with teeth, paracymbium hook-shaped. Epigyne with column-shaped copulatory ducts. It can be distinguished by: General: In male, ocular region with wing-like spines which covers most of PMEs in Y. alatus sp. nov. (Fig. 5E-G), whereas wing-like spines are absent in Y. barbatus sp. nov. (Fig. 10A

Distribution
Known only from the type locality (Fig. 11).

Etymology
The species name comes from Latin adjective "barbatus" meaning "frayed" referring to the frayed or brush-like distal end of the anterior radical process in the male palp.

Discussion
Yuelushannus gen. nov. species were found to have the important diagnostic synapomorphies of erigonines, i.e., desmitracheate tracheal system; female palpal claw absent; male cephalic region with or without modifi cation, pedipalp with tibial apophyses (Hormiga 2000;Locket & Millidge 1953;Merrett 1963;Millidge 1951Millidge , 1977Millidge , 1984, but can be differentiated from all other erigoninae genera by the tibia with two tongue-shaped tibial apophyses densely provided with small teeth; anterior radical apophysis long, running parallel with embolus; dorsal plate of epigyne with scapus posteriorly and columnshaped copulatory ducts. On the basis of the presence of erigonine synapomorphies, we propose that Yuelushannus gen. nov. belongs to the family Linyphiidae.