Echemus viveki Gajbe, 1989

Jiang, Zimin, Ning, Xiaoqi, Yao, Yanbin, Wang, Zhongjing & Liu, Keke, 2025, A new species of the genus Allomicythus, with a first record and the description of the male of Echemus viveki Gajbe, 1989 (Araneae, Gnaphosidae) from China, Zootaxa 5646 (1), pp. 115-123 : 118-120

Echemus viveki Gajbe, 1989

Vernacular name: Ħ埃克e

Figures 2−5

Echemus viveki Gajbe, 1989: 560 , figs 9−13 (female holotype from West Bengal, India, illustrations examined).

Material examined. 1♂, 1♀, CHINA: Xizang Autonomous Region, Shigatse City , Yadong County, Xiasima Town , near the fire brigade of Yadong County , 27°30'02.38"N, 88°54'04.51"E, 2973 m a.s.l., 4 August 2023, Keke Liu, Zimin Jiang, Yanbin Yao leg ; 1♂, 27°29'33.38"N, 88°54'18.16"E, 2958 m a.s.l., other data same as previous ; 1♂, Xiayadong Township, Renqinggang Village , 27°26'00.90"N, 88°55'23.09"E. 2961 m a.s.l., other data same as previous .

Diagnosis. The male of this species resembles that of Echemus angustifrons (Westring, 1861) (see Bosmans and Gavalas 2023: 26, fig. 10H, I) in having the palpal tibia with a thick horn-like retrolateral apophysis and a U-shaped sperm duct, but can be distinguished by the claw-like median apophysis (vs sub-square) and the thick embolus with an inverted C-shaped tip (vs S-shaped) ( Figs 2 C−F, 3). The female is similar to that of E. angustifrons (see Chatzaki and Van Keer 2019: 439, figs 9−12 and Bosmans and Gavalas 2023: 26, fig. 10J) in having a large mushroom-like atrium, but can be separated from it by the shape of the atrium being longer than wide (opposite in E. angustifrons ) and with a distinct bell-like shape as well as the short and mastoid-shaped glandular appendages (vs long and clavate) ( Fig. 4C, D ).

Description. Male. Habitus as in Fig. 2A, B . Total length 5.87, carapace 2.63 long, 1.91 wide, with dense short setae on dorsal side. Eye sizes and interdistances: AME 0.14, ALE 0.12, PME 0.13, PLE 0.13, AME−AME 0.1, AME−ALE 0.02, PME−PME 0.1, PME−PLE 0.06, AME−PME 0.16, AME−PLE 0.13, ALE−ALE 0.38, PLE−PLE 0.47, ALE−PLE 0.05. MOA 0.39 long, front width 0.34, back width 0.34. Chelicerae with six promarginal and one retromarginal teeth. Endites longer than wide, laterally with a row of long setae. Labium slightly longer than wide, with several long setae on surface. Sternum oval, longer than wide, with many long setae on surface, anteriorly flat, posterior end blunt. Leg measurements: I 6.42 (1.37, 1.25, 1.52, 1.33, 0.95); II 6.17 (1.71, 1.01, 1.41, 1.2, 0.84); III 5.71 (1.51, 0.97, 1.16, 1.24, 0.83); IV 7.98 (2.2, 0.99, 1.75, 2.05, 0.99). Spination: I Fe: d2; II Fe: d2, p1; Ti: v1; Mt: v1; III Fe: d5; Ti: p3, r3, v6; Mt: p2, r3, v2; IV Fe: d6, r1; Pa: r1; Ti: p1, r3, v6; Mt: d5, p3, r2, v2. Abdomen 3.24 long, 2.2 wide, with small dorsal scutum, nearly covering 1/6 the length of the abdomen.

Coloration ( Fig.2A,B ). Carapace yellow, with brown radial stripes around longitudinal fovea.Chelicerae yellow-brown. Endites yellow. Labium yellow brown. Sternum yellow-brown, with dark brown margin. Legs yellowish to yellow-brown. Abdomen yellowish to dark brown, postero-medially with seven chevron-like markings.

Palp ( Figs 2C–F , 3 ). Retrolateral tibial apophysis thick and horn-like, shorter than tibia. Cymbium with a broad and blunt retrolateral basal process. Sperm duct U-shaped, not reaching posterior edge of the tegulum. Median apophysis with wide base and a curved lateral margin terminating at a claw-like tip. Embolus thick, subapical part sharp narrowed, strongly curved, apex membranous, directed parallel to the median apophysis’ claw.

Female: Female. Habitus as in Figs 4A, B , 5B . Total length 5.15, carapace 1.91 long, 1.42 wide. Eye sizes and interdistances: AME 0.11, ALE 0.12, PME 0.10, PLE 0.11, AME−AME 0.05, AME−ALE 0.03, PME−PME 0.05, PME−PLE 0.06, AME−PME 0.11, AME−PLE 0.06, ALE−ALE 0.26, PLE−PLE 0.29, ALE−PLE 0.03. MOA 0.29 long, front width 0.26, back width 0.27. Chelicerae with one promarginal and no retromarginal teeth. Legs: tarsal claw with 4–6 teeth; measurements: I 4.75 (1.44, 0.87, 1.02, 0.8, 0.62); II 4.36 (1.28, 0.76, 0.94, 0.79, 0.59); III 3.92 (1.01, 0.61, 0.84, 0.84, 0.62); IV 4.82 (1.27, 0.67, 1.06, 1.19, 0.63). Spination: I Fe: d2; II Fe: d2, p1; Ti: v1; Mt: r1; III Fe: d4, p1; Pa: r1; Ti: d3, p2, r2, v5; Mt: d4, p1, r2, v2; IV Fe: d2; Pa: p1; Ti: p1, r3, v5; Mt: d1, p2, r3. Abdomen ( Fig. 4A, B ) 3.24 long, 2.30 wide, scutum absent.

Coloration ( Fig. 4A, B ). Paler than male. Abdomen white to dark brown.

Epigyne ( Fig. 4C, D ).Atrium very large, mushroom-like and bell-shaped, covering more than 2/3 of the epigynal plate. Epigynal hood narrow, antero-medially located. Copulatory openings located at postero-lateral part of atrium, covered by a protruded edge. Copulatory ducts broad, C-shaped, slightly separated. Glandular appendages mastoidlike, directed anteriorly. Spermathecae peanut-shaped, placed close to each other. Fertilization ducts long, nearly as long as 2/3 of spermathecae, diagonally directed.

Remarks. The female holotype and the specimens of the present study were collected in different localities, but both are close to the border between India and China and they lie close in the Himalayan Mountains. The distance between Tibetan Nayabusta ( India) and Yadong County is about 100 km. Moreover, both specimens have similar habitus and epigyne. For these reasons, we consider them as conspecific.

Distribution. Known from the Himalayas: India ( Gajbe 1989) and China ( Fig. 6 ).

Figures

FIGURE 2. Echemus viveki Gajbe, 1989, male.A. Habitus, black arrow shows the dorsal scutum, dorsal view; B. Same, ventral view; C. Palp, prolateral view; D, F. Same, ventro-retrolateral view; E. Same, retrolateral view. Abbreviations: Em—embolus, MA—median apophysis, RTA—retrolateral tibial apophysis, SD—sperm duct, Scale bars: 0.5 mm (A, B); 0.1 mm (C−F).

FIGURE 3. SEMs of Echemus viveki Gajbe, 1989, male palp. A. Detail of retrolateral tibial apophysis, ventral view; B. Detail of anterior tegulum, ventral view; C. Embolus, ventral view; D. Detail of embolus, ventral view; E. Retrolatero-ventral view; F. Detail of retrolateral tibial apophysis, retrolatero-ventral view; G. Detail of anterior tegulum, retrolatero-ventral view. Abbreviations: Em—embolus, MA—median apophysis, RTA—retrolateral tibial apophysis.

FIGURE 4. Echemus viveki Gajbe, 1989, female. A. Habitus, dorsal view; B. Same, ventral view; C. Epigyne, ventral view; D. Vulva, dorsal view. Abbreviations: At—atrium, CD—copulatory duct, CO—copulatory opening, FD—fertilization ducts, GA—glandular appendages, Ho—hood, Spe—spermatheca. Scale bars: 0.5 mm (A, B); 0.1 mm (C, D).

FIGURE 5. The habitat (A) and the living female specimen of Echemus viveki Gajbe, 1989.

FIGURE 6. Distributional records of Allomicythus youzi sp. nov. (black circle) and Echemus viveki Gajbe, 1989 (red circle) from China.