First description of the male of Oecobiusprzewalskyi Hu & Li, 1987 (Araneae, Oecobiidae) from Shigatse City, Tibet, China

Abstract Background With 90 described species, the genus Oecobius Lucas, 1846 is the largest genus of the family Oecobiidae Blackwall, 1862, five of which are known from China. Since Oceobiusprzewalskyi was described by Hu & Li in 1987, no males of this species have ever been reported. New information The male of Oceobiusprzewalskyi is described for the first time, based on the specimens collected in Tibet Autonomous Region. Morphological description and illustrations are given.

The species Oecobius przewalskyi Hu & Li, 1987 was firstly described, based on female specimens only from Shigatse (Tibet Autonomous Region, China) (Hu and Li 1987).Recently, the authors examined specimens collected from the type locality and found that one male and one female seemed to be this species, based on comparison with the illustration from Hu and Li (1987).Based on the currently-known specimens, this species is only distributed in Shigatse City, Tibet.The aim of the current paper is to report the male for the first time and re-describe the female, with provision of detailed morphological photos.

Materials and methods
The specimens examined in this study were deposited in the Centre for Behavioural Ecology and Evolution, College of Life Sciences, Hubei University in Wuhan.Specimens were examined using an OLYMPUS SZX7 stereomicroscope.Photographs were taken with a LEICA M205 C stereomicroscope and OLYMPUS SXZ16 microscope and final multifocal images were produced with Helicon Focus (Version 7.7.0).The male palp was examined and photographed after dissection.The epigyne was examined after being dissected from the spider's body.The epigyne was removed and treated in a warmed 0.1 mg/ml Protease K solution before study.All morphological measurements were calculated using a Leica M205 C stereomicroscope.Eye diameters were taken at the widest point.Leg measurements were given as total length of leg (femur, patella, tibia, metatarsus, tarsus).All measurements were in millimetres (mm).Coddington (1990) and Magalhães and Santos (2018) for male palps.Abbreviations: ALE anterior lateral eyes, AME anterior median eyes, CD copulatory duct, CO copulatory opening, E embolus, EA embolic apophysis, I, II, III, IV legs I to IV, PLE posterior lateral eyes, PME posterior median eyes, Sp spermatheca, TA tegular apophysis, TL I tegular lobe I. Leg formula: IV-III-II-I.Abdomen dorsally yellowish-brown with white irregular marks, cardiac mark light brown.Abdomen ventrally light yellow with few white irregular marks (Fig. 1D).

Oecobius przewalskyi Hu & Li, 1987
Palp as in diagnosis.Embolus (E) short and small, located in the median of bulb in ventral view and bent prolaterally; tegular apophysis (TA) four-branched, upper branch strongly sclerotic, with curled end and an outside tip, median branch small and rounded, two lower branches horn-like; embolic apophysis (EA) point to upward side of bulb and with serrated margin, dorsal embolic apophysis (EA) covered; tegular lobe I (TL I) large and thick, with two apophyses, upper apophysis pointed and lower apophysis rounded (Fig. 1A-C).Copulatory organ as in diagnosis.Epigyne without process and scape.Copulatory openings (CO) located in posterior side; copulatory ducts (CD) visible in ventral view; vulva with wrinkles in posterior side, left copulatory duct (CD) pointing to 1 o'clock; spermathecae (Sp) oval and membranous, located in anterior side (Fig. 2).

Diagnosis
Male of Oecobius przewalskyi can be distinguished from other Oecobius species by 1. tegular apophysis (TA) four-branched, upper branch with curled end and an outside tip, median branch small and rounded, two lower branches horn-like; 2. embolic apophysis (EA) with serrated margin; 3. tegular lobe I (TL I) thick, with two apophyses, upper apophysis pointed and lower apophysis rounded (Fig. 1A-C).Female of O. przewalskyi can be distinguished from the other species of Oecobius by 1. epigyne without process and scape; 2. copulatory ducts (CD) visible in ventral view, left copulatory duct (CD) pointing to 1 o'clock (Fig. 2).

Notes
Although we did not examine the type specimens of O. przewalskyi, the left copulatory duct (CD) which is pointing to 1 o'clock and the two oval spermathecae (Sp) shown in the original illustrations (Fig. 2) leave no doubts that our identification is correct.