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

Fig. 26

Eotrechus pumat J. Polhemus, Tran & D. Polhemus, 2009: 34-37, figs 11-17 (type locality: Pu Mat, Nghe An).

Material examined.

Vietnam • 9 ♂♂, 7 ♀♀ (apterous), 5 nymphs; Nghe An Province, Pu Mat National Park, Khe Kem waterfall & stream, site #1; 18 Apr. 2013; Tran A.D. et al. leg.; TAD1310; ZVNU • 4 ♂♂, 4 ♀♀ (apterous), 3 nymphs; same locality as preceding; 30 Aug. 2020; Tran A.D., Le P.L., Nguyen T.C. leg.; TAD20-06; ZVNU .

Diagnosis.

Size: apterous males, length 5.70-6.10 (holotype 5.90), width 1.99-2.19 (holotype 2.13); apterous females, length 6.49-8.44, width 2.33-2.55. Dorsum covered with silvery or greenish pubescence, background colour brown with yellowish markings. Mesosternum ca. 4.5 × (male) and 4.0 × (female) length of metasternum, posterior margin of metasternum with a median fringe of closely-set, black setae. Male: fore femur simple, distal part slightly constricted; abdominal venter with patch of long, yellow, soft setae on mediosternites II-VI; sternum VII ca. 2.1 × length of two preceding sterna combined; posterior margin of sternum VII with a deep, rectangular notch. Male genitalia: pygophore with a pair of broad, thick, posterolateral projections, each bearing prominent tubercles on both sides. Female: flexor side of fore femur with four stiff setae at basal part; sternum VII ca. 1.6 × length of two preceding sterna combined; genitalia visible in lateral view.

Remarks.

Eotrechus pumat and E. vietnamensis are sister species, as they share many characteristics. They can be distinguished by using the revised key above. Males can be readily separated based on the structure of the posterolateral projections of the pygophore. Females are almost indistinguishable. The only difference between females of these two species is that sternum VII of E. pumat is longer, ca. 1.6 × the length of the two preceding sterna combined, whereas that of E. vietnamensis is ca. 1.2 × the length of the two preceding sterna combined.

Distribution.

Vietnam: Nghe An ( Polhemus et al. 2009) (Fig. 26 ).

Species unassigned to a group

Figures

Figure 26. Distribution records of species of Eotrechus. Circles represent E. longipes species group; squares represent E. petraeus species group; stars represent E. vietnamensis species group.