Tetragnatha tortilis Li & Liu, 2022

Li, Song-lin, Liu, Ping & Peng, Xian-jin, 2022, Three new species of the genus Tetragnatha Latreille, 1804 (Araneae, Tetragnathidae) from China, ZooKeys 1125, pp. 87-101 : 87

Tetragnatha tortilis Li & Liu sp. nov.

Figs 5 , 6 , 7

Type material.

Holotype ♂: China, Yunnan Province, Tengchong County: Jietou Township, Datang Village: 25.4277°N, 98.4129°E, 1952 m, 18.V.2006, P. Hu leg. (Hu060518). Paratypes: 1♂ 1♀, same data as holotype (Hu060518); 1♀, 25.7456°N, 98.6963°E, 2030 m, 20.V.2006, X.J. Peng & P. Hu leg. (Peng060520); 1♂, 25.4202°N, 98.4095°E, 1870 m, 17.V.2006 (Peng060517), 2♂♂, 25.7456°N, 98.6963°E, 2030 m, 15.V.2006 (Peng060515), 3♂♂ 2♀♀, 25.7572°N, 98.6946°E, 2078 m, 16.V.2006 (Peng060516), 1♂, 25.4202°N, 98.4095°E, 1878 m, 19.V.2006 (Peng060519), X. J. Peng et al. leg.; 1♂, Houqiao Township: 25.3539°N, 98.2549°E, 1785 m, 28.V.2006 (Wang060528-1), 1♀, Gaoshidong Village, 25.3986°N, 98.3053°E, 2374 m, 27.V.2006 (Wang060527-2), 3♀♀, Zhaobitang Village, 25.5380°N, 98.2094°E, 2480 m, 29.V.2006 (Wang060529-1), X.P. Wang & P. Hu leg.; 2♂♂ 1♀, Mingguang Township: Zizhi Village, Cizhu River, 25.7666°N, 98.6174°E, 2120 m, 21.V.2006, C.M. Yin & J.F. Hu leg. (YHY09).

Etymology.

The specific epithet is derived from the Latin adjective tortilis (twisted), referring to the twisted distal end of conductor.

Diagnosis.

The new species resembles T. pinicola L. Koch, 1870 ( Zhu et al. 2003: figs 87A-G, 88A-G; Marusik 2010: fig. 7). Males of the two species are similar in the presence of an elongated tooth in the upper row of the chelicera in males (T), the conductor having 2 folds, and the shape of paracymbium, but can be distinguished by: (1) the dorsal spur of chelicera is straight in ventral view in T. tortilis sp. nov. (Fig. 5E ) (vs. distal end curved; fig. 88C in Zhu et al. [2003]); (2) the absence of an auxiliary guide tooth of the lower row of the chelicera (Fig. 5E, F ) (vs. present; fig. 88C in Zhu et al. [2003]); (3) the distal portion of conductor is twisted and has a small knot (Fig. 5G ) (vs. hook-shaped; fig. 7 in Marusik [2010]). Females of the two species are similar in the presence of 2 pairs of spermathecae and the absence of a central membranous sac in the vulva, but can be distinguished by the anterior spermathecae 4 × larger than posterior in T. tortilis sp. nov. (Fig. 6H ) (vs. anterior spermathecae ~ 1/2 × posterior spermathecae; fig. 87G in Zhu et al. [2003]). Both sexes of the two species can be distinguished by the sternum which is yellowish brown and without a stripe in T. tortilis sp. nov. (vs. dark brown with yellow stripe).

Description.

Male (holotype) (Fig. 5A-F ). Total length 4.97. Carapace 1.72 long, 1.05 wide, yellowish brown, fovea, cervical, and radial grooves distinct. Eye sizes and interdistances: AME 0.06, ALE 0.07, PME 0.08, PLE 0.09; AME-AME 0.10, AME-ALE 0.14, PME-PME 0.15, PME-PLE 0.13, MO anterior width 0.24, posterior width 0.31, length 0.27. Clypeus 0.10 high. Labium brown, with thickened edge. Sternum yellowish brown with dark edge. Legs yellowish brown, with sparse spines. Leg measurements: I, 15.59 (4.04, 5.27, 4.87, 1.41); II, 9.96 (2.90, 3.10, 2.98, 0.98); III, 4.46 (1.50, 1.24, 1.12, 0.60); IV, 8.96 (2.93, 2.64, 2.66, 0.73). Chelicera: yellow, ~ 2/3 length of carapace; dorsal spur tapered; AXu absent; upper row with 7 teeth: Gu curved and almost equal to sl in size, T present, 4 rsu decreasing in size gradually; AXl absent; lower row with 7 teeth: Gl tiny, L2 slightly smaller than L3, L3 largest, all other teeth smaller than L2 and almost equal in size. Abdomen 3.23 long, 0.85 wide, dorsum grayish yellow, dark folium covering almost complete dorsum, with scattered pale spots and a brown longitudinal line medially, 2 pairs of sigillae; venter grayish yellow, anterior part with sparse pale spots.

Palp (Fig. 5G-K ). Paracymbium with blunt distal end, notch inconspicuous, translucent lobe elongated, extended to the end, ~ 1/3 of the width of paracymbium, knob spherical. Tegulum oval, ~ 2 × wider than long. Conductor with 2 folds, distal portion twisted considerably, and directed to dorsal side. Embolus partially enveloped by conductor.

Female (paratype Hu060518) (Fig. 6A-F ). Total length 5.70. Carapace 1.77 long, 1.24 wide. Eye sizes and interdistances: AME 0.07, ALE 007, PME 0.08, PLE 0.08; AME-AME 0.10, AME-ALE 0.18, PME-PME 0.12, PME-PLE 0.14. MO anterior width 0.25, posterior width 0.33, length 0.3. Clypeus 0.07 high. Leg measurements: I, 15.33 (4.21, 5.05, 4.73, 1.34); II, 9.48 (2.91, 2.94, 2.70, 0.93); III, 4.4 (1.48, 1.25, 1.00, 0.67); IV, 8.25 (2.72, 2.50, 2.28, 0.75). Chelicera: AXu absent; upper row with 7 teeth: Gu curved, U2 largest, other teeth decreasing in size gradually; AXl absent; lower row with 6 teeth: Gl almost equal to L3 in size, L2 largest, other teeth decreasing in size gradually. Abdomen 3.92 long, 1.32 wide, dorsum pale yellow; venter with pale spots on both sides; otherwise, remaining pattern same as in male.

Epigyne (Fig. 6G, H ). Fold ~ 3 × wider than long. Vulva composed of 2 pairs of spermathecae, anterior pair larger, oval and almost touched each other, posterior pair smaller, spherical, and spaced by 3 diameters. Central membranous sac absent.

Distribution.

Known only from the type locality (Fig. 7 ).

Figures

Figure 5. Tetragnatha tortilis sp. nov., holotype ♂ A-C habitus A dorsal view B lateral view C ventral view D-F left chelicera D upper view E inner view F lower view G, K conductor and embolus detail H-J left palp H prolateral view I ventral view J retrolateral view. Scale bars: 1 mm (A-C); 0.2 mm (D-F, H-J); 0. 1 mm (G, K).

Figure 6. Tetragnatha tortilis sp. nov., paratype ♀ A-C habitus A dorsal view B lateral view C ventral view D-F left chelicera D upper view E inner view F lower view G, H female genitalia G epigynal fold, ventral view H vulva, dorsal view. Scale bars: 1 mm (A-C); 0.5 mm (D-F); 0.2 mm (G, H).

Figure 7. Collection localities for Tetragnatha bifurcata sp. nov., Tetragnatha bimaculata sp. nov., and Tetragnatha tortilis sp. nov. in China.