Eotrechus fansipan J. Polhemus, Tran & D. Polhemus, 2009

Fig. 25

Eotrechus fansipan J. Polhemus, Tran & D. Polhemus, 2009: 32-34, figs 1, 4-10, 17 (type locality: Lao Cai, Vietnam).

Material examined.

Vietnam •, 8 ♂♂, 8 ♀♀ (apterous); Lao Cai Province, Sa Pa, Cat Cat, Ho stream (feeder stream of Muong Hoa stream); 22 Apr. 2011; Dinh N.H. et al. leg.; DNH11.02; ZVNU • 1 ♂, 1 ♀ (apterous); same locality as preceding; 27 Oct. 2020; Tran A.D. leg.; TAD20-23; ZVNU • 3 ♂♂, 1 ♀ (apterous); Lao Cai Province, Sa Pa, Sin Chai, Muong Hoa stream; 22 Apr. 2011; Dinh N.H. et al. leg.; DNH11.03; ZVNU • 1 ♂ (apterous); Lao Cai Province, Sa Pa, waterfall and stream by roadside from Sa Pa town to Nui Xe, ca. 13 km from Sa Pa town; 23 Apr. 2011; Dinh N.H. et al. leg.; DNH11.10; ZVNU • 5 ♂♂ (apterous); same locality as preceding; 30 May 2013; Tran A.D. leg.; TAD1320; ZVNU • 1 ♂ (apterous); same locality as preceding; 25 Oct. 2013; Tran A.D. et al. leg.; TAD1358b; ZVNU • 1 ♂, 4 ♀♀ (apterous); same locality as preceding; 25 Oct. 2020; Tran A.D. & Nguyen V.V. leg.; TAD20-18; ZVNU • 3 ♂♂, 2 ♀♀ (apterous); Lao Cai Province, Sa Pa, waterfall by roadside from Thac Bac waterfall to Nui Xe, ca. 500 m from Thac Bac waterfall; 31 May 2013; Tran A.D. leg. TAD1321; ZVNU • 1 ♀ (apterous), 1 ♂ (macropterous); Lao Cai Province, Sa Pa, waterfall by roadside from Thac Bac waterfall to Nui Xe, ca. 1 km from Thac Bac waterfall; 31 May 2013; Tran A.D. leg.; TAD1322; ZVNU • 3 ♂♂, 3 ♀♀ (apterous); Lao Cai Province, Sa Pa, Sin Chai, Sin Chai stream, site 1; 27 Oct. 2013; Tran A.D. et al. leg.; TAD1363; ZVNU • 2 ♂♂, 3 ♀♀ (apterous), 1 nymph; Lao Cai Province, Sa Pa, Muong Hoa stream, upstream of Sin Chai; 26 Oct. 2020; Tran A.D. & Nguyen T.A.N. leg.; TAD20-22; ZVNU .

Diagnosis.

Size: apterous males, length 7.66-8.50 (holotype 8.50), width 2.48-2.74 (holotype 2.74); macropterous male, length 9.80, width 2.56; apterous females, length 8.55-9.50, width 2.77-2.87; macropterous female, length 9.54-9.60. Dorsum mainly brown, venter mainly light-brown. Mesosternum ca. 3.2 × (male) and 2.95 × (female) length of metasternum. Male: fore femur incrassate, slightly constricted before apex, basal part with broad tubercle bearing patch of minute, dark setae, flexor side of femur with a row of ca. 10 long, stiff setae; fore tibia slightly curved in the middle, long, stiff setae scattered on extensor side and denser at distal part; abdominal sterna III-VI medially depressed, sternum VII broadly depressed, distinctly longer than two preceding sterna combined, posterior margin emarginated into a notch about two-fifths of sternum VII length. Male genitalia: segment VIII longer than sternum VII, posteroventral margin almost straight; pygophore with small lateral tubercle, ventral surface convex in lateral view; caudal projection of pygophore short, plate-like, with dense patch of long, soft setae on ventrolateral sides, apical margin almost straight; paramere small, ovoid; proctiger trilobed, posterolateral lobes small, posteroventral surface with dense patch of long, brush-like setae. Female: fore femur more slender than in male, femur without basal tubercle, with ca. 12 long, stiff setae along flexor side; fore tibia almost straight; abdomen, in lateral view, tapering towards apex; sternum VII ca. 1.1 × length of two preceding sterna combined, not enclosing genitalia.

Remarks.

Four species, Eotrechus fansipan, E. pingae, E. luaae, and E. elongatus are closely related to each other, by sharing similarities in the structure of the fore leg and genitalia of the male. Polhemus et al. (2009) provided a comparison among three species, Eotrechus fansipan, E. pingae, and E. luaae . Herein, we provide further comparison, with the addition of E. elongatus (Table 2).

Distribution.

Vietnam: Lao Cai (Polhemus et al. 2009) (Fig. 25).