Otacilia horizon sp. nov. (MŴṚff)

Figs 25–27

Type material. Holotype ♁, CHINA: Yunnan Province: Baoshan City, Longyang District, Lujiang Town (24.928124°N, 98.797474°E, 1927 m a.s.l.), 23 Nov. 2017, leg. Yannan Mu.

Paratypes: 2 ♁ 5 ♀, with same data as holotype; 7 ♁ 6 ♀, Taibaoshan Forest Park (25.118748°N, 99.149809°E, 1787 m a.s.l.), 21 Nov. 2017, leg. Yannan Mu ; 2 ♁ 4 ♀, Taibaoshan Forest Park (25.116509°N, 99.153918°E, 1759 m a.s.l.), 20 Nov. 2017, leg. Yannan Mu ; 1 ♁ 1 ♀, Longling County, Xiaoheishan Nature Reserve (24.556765°N, 98.821807°E, 1840 m a.s.l.), 28 Nov. 2017, leg. Yannan Mu.

Etymology. This specific name is derived from the Latin word “ horizon ”, referring to the transverse embolus; noun in apposition.

Diagnosis. This new species resembles O. yangi Zhang, Fu & Zhu, 2009 in having a similar position and shape of the copulatory openings, but can be recognized by: 1) presence of a triangular apophysis prolaterally at the base of the retrolateral tibial apophysis (vs absent, cf. Fig. 26B and fig. 4 in Zhang et al. [2009]), 2) the transverse embolus (vs upwards, cf. Fig. 26C and fig. 3 in Zhang et al. [2009]), 3) the thicker copulatory ducts (vs thin, cf. Fig. 26E and fig. 7 in Zhang et al. [2009]), and 4) the absence of glandular appendages (vs clavate-shaped, cf. Fig. 26F and fig. 8 in Zhang et al. [2009]).

Description. Male (Holotype): total length 4.10, carapace 2.01 long, 1.78 wide; abdomen 2.09 long, 1.29 wide. Eye sizes and interdistances:AME 0.15, ALE 0.15, PME 0.12, PLE 0.15; AME–AME 0.05, AME–ALE 0.01, ALE– ALE 0.34, PME–PME 0.14, PME–PLE 0.08, PLE–PLE 0.54, ALE–PLE 0.10. EAW 0.72, CRW 0.93, EAW/CRW 0.77, CRW/CW 0.52. MOA 0.36 long, anterior width 0.32, posterior width 0.39. CH 0.16, CH /AME 1.07. Labium 0.21 long, 0.29 wide. Sternum 1.12 long, 0.98 wide. Leg measurements: Ⅰ 8.16 (2.01, 0.71, 2.45, 1.87, 1.12), II 7.18 (1.98, 0.76, 1.89, 1.53, 1.02), III 5.91 (1.63, 0.67, 1.35, 1.40, 0.89), IV 9.39 (2.64, 0.87, 2.22, 2.48, 1.18). Spination: femur I d 2 pl 4, femur II d 1 pl 2, femur IV d 1, tibia Ⅰ pv 8 rv 8, tibia II pv 7 rv 7, metatarsus Ⅰ pv 4 rv 4, metatarsus II pv 4 rv 3.

Coloration. Carapace yellow, with several shapes resembling flowing water droplets beside fovea. Abdomen gray, with yellow dorsal scutum and black pattern besides dorsal scutum anteriorly and three black transverse stripes posteriorly (Fig. 25A, B). Legs yellow.

Palp as in Figs 26A–D, 27A–C. Femoral apophysis well-developed, located near middle of femur. Prolateral tibial apophysis distinct, semicircular. Retrolateral tibial apophysis base wide, digitiform tip, with small triangular apophysis prolaterally at base and large triangular apophysis retrolaterally at base. Tegulum pyriform; tegular apophysis absent. Sperm duct distinct, tapering from retrolateral side of tegulum to embolus. Embolus long, transverse, extending to retrolateral margin of cymbium. Conductor absent.

Female (Paratype): total length 5.58, carapace 2.21 long, 1.94 wide; abdomen 3.37 long, 2.08 wide. Eye sizes and interdistances: AME 0.15, ALE 0.16, PME 0.13, PLE 0.15; AME–AME 0.05, AME–ALE 0.01, ALE–ALE 0.35, PME–PME 0.14, PME–PLE 0.09, PLE–PLE 0.58, ALE–PLE 0. 11. EAW 0.76, CRW 1.03, EAW/CRW 0.74, CRW/CW 0.53. MOA 0.38 long, anterior width 0.34, posterior width 0.41. CH 0.14, CH /AME 0.93. Labium 0.18 long, 0.34 wide. Sternum 1.29 long, 1.15 wide. Leg measurements: Ⅰ 9.35 (2.50, 0.77, 2.81, 2.08, 1.19), II 7.53 (2.04, 0.74, 2.02, 1.66, 1.07), III 6.27 (1.63, 0.71, 1.38, 1.60, 0.95), IV 9.28 (2.64, 0.82, 2.23, 2.58, 1.01). Spination: femur I d 2 pl 5, femur II d 1 pl 2, femora III–IV d 1, tibia Ⅰ pv 9 rv 9, tibia II pv 8 rv 7, metatarsus Ⅰ pv 4 rv 4, metatarsus II pv 4 rv 3. Other characters as for male, except with three black chevron stripes and two transverse black stripes, and dorsal scutum absent (Fig. 25C, D).

Epigyne as in Figs 26E–F, 27D–E. Epigynal plate sclerotized. Median septum V-shaped. Copulatory openings round, located at middle parts of plate, separated by about 3 times diameter of spermathecae. Copulatory ducts extremely thick, curved and connecting with bursa. Connecting tubes thinner than copulatory ducts, straight, close to each other. Bursa oval, transparent. Spermathecae oval, separated by less than their diameter. Fertilization ducts located on anterior margin of spermathecae.

Distribution. China (Yunnan Province).