Tmarus taibaiensis Song & Wang, 1994

Zhang, Rui & Zhang, Feng, 2023, Diversity of the genus Tmarus Simon, 1875 from Xiaolong Mountains in western China (Araneae: Thomisidae), Zootaxa 5301 (1), pp. 75-93 : 85-92

Tmarus taibaiensis Song & Wang, 1994

Figs 43–50

Tmarus taibaiensis Song & Wang, 1994: 47 , figs 2A–D. Song & Zhu 1997: 55, figs 31A–B; Song, Zhu & Chen 1999: 500, fig. 284N.

Material examined. CHINA: Gansu: 1♁ 4♀, Wushan County, Longtai Town, Shangheyu Village , 34°32′5″N, 104°51′13″E, 2201m, 22 August 2021, Rui Zhang leg. ; 3♁ 5♀, Wushan County, Yanan Town, Woniu Mountain Forest Park , 34°28′31″N, 104°50′2″E, 2552m, 27 June 2022, Zhaoyi Li leg.

Diagnosis. Males of this species resemble those of T. piger Walckenaer, 1802 ( Song & Zhu 1997: 51, figs 28C–D) in having RTA curved dorsally, but can be distinguished from the latter by the following combination of characters: (1) embolus slim (vs. thick in T. piger ); (2) embolus arising from tegulum at 11 to 12-o’clock-position (vs. 12 to 13-o’clock-position in T. piger ); (3) tibia with three apophyses (vs. two apophyses in T. piger ). Females of T. taibaiensis are also similar to those of T. piger in having a broad atrium, but can be distinguished from the latter by the following characters: (1) copulatory ducts tube-shaped (vs. swollen in T. piger ); (2) spermathecae large, ca. 1/3 of vulva width (vs. small, 1/4 width of vulva in T. piger ).

Redescription. Male: Total length 3.90. Prosoma 1.69 long, 1.66 wide; opisthosoma 2.27 long, 1.45 wide. Middle longitudinal band of carapace yellowish, 1/4 of dorsal carapace width. Two black triangular patches at the end of carapace. Eye sizes and interdistances: AME 0.05, ALE 0.17, PME 0.06, PLE 0.13, AME–AME 0.14, AME–ALE 0.15, PME–PME 0.23, PME–PLE 0.30 AME–PME 0.30, ALE–PLE 0.29. MOA 0.32 long, front width 0.15, back width 0.24. Leg measurements: I 7.10 (1.83, 0.73, 2.04, 1.47, 1.03); II 7.32 (1.92, 0.72, 2.02, 1.75, 0.91); III 4.41 (1.24, 0.47, 1.22, 0.91, 0.57); IV 4.64 (1.42, 0.49, 1.20, 0.99, 0.54). Leg formula: 2143. Abdomen greyish brown dorsally, white centrally.

Palp ( Figs 47–48 ). VTA finger-like, apex slightly curved; RTA with thin apex, extending straight dorsally; ITA longer than VTA, bending outwards. Tegulum flat; embolus slender, originating about ~ 11 o’clock position, terminating about ~ 4 o’clock position.

Female: total length 5.54. Prosoma 1.64 long, 1.70 wide; opisthosoma 3.90 long, 3.01 wide. Carapace brown, length almost equal to width, and covered with seta. A longitudinal band in the center of the carapace, ca. 1/4 of carapace width. Two black triangular patches along the posterior margin. Eye sizes and interdistances: AME 0.06, ALE 0.15, PME 0.08, PLE 0.12, AME–AME 0.17, AME–ALE 0.16, PME–PME 0.27, PME–PLE 0.36, AME–PME 0.29, ALE–PLE 0.27. MOA 0.30 long, front width 0.29, back width 0.43. The sternum with many small black spots. Abdomen pale with many small black spots, dorsally bright greyish in the centre, dark greyish on the sides. Posteriorly with three symmetrical transverse stripes. Leg measurements: I 5.84 (1.72, 0.77, 1.46, 1.12, 0.77); II 5.76 (1.83, 0.83, 1.49, 1.19, 0.72); III 4.19 (1.30, 0.61, 1.01, 0.68, 0.62); IV 4.24 (1.48, 0.53, 0.96, 0.74, 0.53). Leg formula: 1243.

Epigyne ( Figs 49, 50 ). Atrium wide, located at anterior portion of epigynal plate, with delimited margin anteriorly and laterally, length is slightly longer than width. Hood absent. Copulatory openings located at basolateral atrial borders, widely separated. Copulatory ducts short, thick and longitudinal. Spermatheca globular, large, ca. 1/3 of vulva width; fertilization ducts short, acicular.

Distribution. China (Gansu, Shaanxi). Habitat as in Figs 7, 9 .

Remark. We provide the first description of the female of T taibaiensi s. Both males and females were collected in the same locality. We matched both sexes based on morphology of the male and female (newly collected females have general appearance as males, Figs 43–46 ), and DNA barcoding data (the genetic distance between the male and female voucher specimens was 1.51%).

Figures

FIGURES 43–46. Tmarus taibaiensis Song & Wang, 1994. 43–44 Male habitus (43 dorsal, 44 ventral); 45–46 Female habitus (45 dorsal, 46 ventral).

FIGURES 47–50. Tmarus taibaiensis Song & Wang, 1994. 47–48 Left male palp (47 ventral, 48 retrolateral); 49 Epigynum, ventral view; 50 Vulva, dorsal view.A = atrium; CD = copulatory duct; CO = copulatory opening; E = embolus; FD = fertilization duct; ITA = intermedial tibial apophysis; RTA = retrolateral tibial apophysis; S = spermatheca; T = tegulum; VTA = ventral tibial apophysis.

FIGURES 2–9. Habitats of Tmarus speicies treated in this paper. 2 T. orientalis Schenkel, 1963; 3 T. piger Walckenaer, 1802; 4 T. qinlingensis Song & Wang, 1994; 5 T. rimosus Paik, 1973; 6 T. subqinlingensis sp. nov.; 7, 9 T. taibaiensis Song & Wang, 1994; 8 T. zhui Sherwood & Li, 2021.