Xantharia baizilongi Chu & Li sp. nov.

Figs 6, 7, 8, 11B

Type material.

Holotype: 1♂ (IZCAS-Ar44621), China, Yunnan, Xishuangbanna, Mengla County, Menglun Town, Xishuangbanna Tropical Botanical Garden, 21°53.886′N, 101°16.719′E, 568 m, hand catch in leaf litter, 12 May 2019, Z. Bai leg. Paratypes: 1♂ (IZCAS-Ar44622) and 2♀ (IZCAS-Ar44623, 44624), same data as holotype.

Etymology.

The specific name is a patronym in honour of the collector Zilong Bai; noun (name) in genitive case.

Diagnosis.

The new species resembles X. floreni Deeleman-Reinhold, 2001 (cf. Figs 6 - 8, 11B and Deeleman-Reinhold 2001: 217, figs 235, 246, 247, 257-263) as the males have a similar long looping sperm duct (Fig. 6A-C), wide and elliptical embolic base (Fig. 6B) and females have similar laminar fertilization ducts (Fig. 7B). Males can be distinguished by the embolic tip not exceeding bulb distally (Fig. 6B; present), by the palp with conductor without tegular apophysis (Fig. 6A-C; vs. palp with indistinct conductor and tegular apophysis), and by the retrolateral tibial apophysis arising from rear part of the tibia distally, invisible in ventral view (Fig. 6A-C; vs. retrolateral tibial apophysis arising from middle part of tibia distally, visible in ventral view). Females can be distinguished by the epigyne without anterior hood (Fig. 7A; present), by the vulva with glandular appendages (Fig. 7B; absent), by the primary spermathecae and secondary spermathecae connected to each other (Fig. 7B; vs. primary spermathecae and secondary spermathecae separated from each other), and by the primary spermathecae larger than secondary spermathecae (Fig. 7B; vs. primary spermathecae smaller than secondary spermathecae). This species also resembles X. galea Zhang, Zhang & Fu, 2010 (cf. Figs 6 - 8, 11B and Zhang et al. 2010: 66, figs 1-11) as the males have a similar long looping sperm duct (Fig. 6A-C), wide and elliptical embolic base (Fig. 6B), membranous conductor (Fig. 6A-C), and females have similar tubular copulatory ducts (Fig. 7B) and laminar fertilization ducts (Fig. 7B). Males can be distinguished by the embolus originating 8:00 o’clock, embolic tip not exceeding bulb distally, with slight retrolateral curvature (Fig. 6B; vs. embolus originating 9:00 o’clock, embolic tip exceeding bulb distally, with slight prolateral curvature), and by the long retrolateral tibial apophysis (Fig. 6A-C; vs. short retrolateral tibial apophysis). Females can be distinguished by the epigyne without an anterior hood (Fig. 7A; present), by the copulatory openings triangular (Fig. 7A; vs. copulatory openings circular), by the vulva with glandular appendages (Fig. 7B; absent), by the primary spermathecae and secondary spermathecae connected to each other (Fig. 7B; vs. primary spermathecae and secondary spermathecae separated and with common horizontal plane), and by the primary spermathecae larger than secondary spermathecae (Fig. 7B; vs. primary spermathecae smaller than secondary spermathecae).

Description.

Male (holotype; Figs 8A, B, 11B). Total body length 3.62, carapace 1.65 long, 1.23 wide, opisthosoma 1.97 long, 0.95 wide. Eye sizes and interdistances: AME 0.09, ALE 0.11, PME 0.08, PLE 0.10; AME-AME 0.06, AME-ALE 0.02, PME-PME 0.11, PME-PLE 0.09, AME-PME 0.09, ALE-PLE 0.04. Carapace yellowish-brown without pattern, pear-shaped; fovea reddish-brown. Chelicerae yellowish-brown, with several setae on anterior surface, with two promarginal and two retromarginal teeth. Endites yellowish-brown, longer than wide, widest anteriorly, concave laterally, with diagonal depression in middle, subapically with semicircular membranous area and dense scopula. Labium reddish-brown, nearly isosceles trapezoidal, with constriction subbasally and sparse scopula apically. Sternum yellow without pattern, margin yellowish-brown, narrowing anteriorly, with precoxal triangles and intercoxal extensions. Legs yellowish without pattern; legs I distinctly darker and stouter than legs II-IV. Leg spination: femora II pl 2, III-IV do 2; tibiae III-IV pl 1; metatarsi III-IV pl 1 rl 1 plv 2 rlv 2. Palp and leg measurements: palp 1.49 (0.56, 0.21, 0.29, -, 0.43), I 4.44 (1.22, 0.78, 1.04, 0.98, 0.42), II 3.73 (1.09, 0.62, 0.81, 0.82, 0.39), III 3.35 (0.95, 0.50, 0.65, 0.87, 0.38), IV 4.46 (1.28, 0.63, 0.96, 1.16, 0.43). Leg formula: 4123. Dorsal opisthosoma grey, posteriorly yellow occupying more than half of dorsal surface, with dark margin around spinnerets. Lateral opisthosoma with dark stripes. Ventral opisthosoma grey with dark margin around spinnerets. Spinnerets yellowish.

Palp (Fig. 6A-C). Retrolateral tibial apophysis short, curvature distally, with wide base and narrow tip. Bulb oval, subtegulum sclerotized, visible in ventral view; sperm duct distinct, running around tegulum. Embolus originating at 8:00 o’clock, embolic base sclerotized, wide and elliptical; embolic tip membranous, situated distally at 12:00 o’clock . Conductor membranous, nearly fan-shaped, originating distally to bulb.

Female (paratype; Fig. 8C, D). Total body length 3.71, carapace 1.69 long, 1.23 wide, opisthosoma 2.02 long, 1.11 wide. Eye sizes and interdistances: AME 0.09, ALE 0.10, PME 0.08, PLE 0.11; AME-AME 0.06, AME-ALE 0.02, PME-PME 0.11, PME-PLE 0.08, AME-PME 0.09, ALE-PLE 0.04. Carapace yellowish without pattern, ocular area yellowish-brown; fovea shorter. Chelicerae, endites and labium yellowish; endites with indistinct diagonal depression in middle. Sternum without distinct precoxal triangles. Leg spination: femora II-IV do 2; tibiae III-IV pl 1; metatarsi III-IV pl 1 rl 1 plv 2 rlv 2. Palp and leg measurements: palp 1.51 (0.57, 0.24, 0.29, -, 0.41), I 4.72 (1.30, 0.78, 1.13, 1.03, 0.48), II 4.07 (1.14, 0.63, 0.88, 0.97, 0.45), III 3.73 (1.04, 0.55, 0.72, 1.01, 0.41), IV 4.91 (1.40, 0.65, 1.13, 1.25, 0.48). Leg formula: 4123. Dorsal opisthosoma grey with dark spots. Other characters same as holotype.

Epigyne (Fig. 7A, B). Epigynal plate simple; copulatory openings triangular, originating centrally to epigynal field. Copulatory ducts long, with sharp twist at its base, presenting spherical. Glandular appendages round. Primary spermathecae large, elliptical, almost adjacent to each other; secondary spermathecae small, nearly globular, separated by more than their diameter; primary spermathecae and secondary spermathecae connected to each other. Fertilization ducts originating anteriorly to primary spermathecae, pointing laterally.

Variation.

Paratype male: total body length 3.33, carapace 1.58 long, 1.14 wide, opisthosoma 1.75 long, 1.04 wide. Second paratype female: total body length 4.30, carapace 1.80 long, 1.38 wide, opisthosoma 2.50 long, 1.24 wide.

Distribution.

China (Yunnan, type locality; Fig. 12).