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

Tran, Anh Duc, Zettel, Herbert & Sites, Robert W., 2023, Revision of the genus Eotrechus Kirkaldy (Hemiptera, Heteroptera, Gerridae), with descriptions of six new species, Deutsche Entomologische Zeitschrift 70 (1), pp. 69-111 : 69

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 ).

Figures

Figure 25. Distribution records of species of Eotrechus. Squares represent E. kalidasa species group; circles represent E. pingae species group; triangles represent species unassigned to a group.