Eotrechus sinensis Andersen, 1982

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 sinensis Andersen, 1982

Fig. 25

Eotrechus sinensis Andersen, 1982: 17-19, figs 12, 31 (type locality: Fukien, China).

Eotrechus sinensis : Andersen (1998: 6) (checklist).

Material examined.

Material not available for examination.

Diagnosis

(after Andersen 1982). Size: apterous female: length 8.2, width 2.8. Male unknown. Female: Mesosternum ca. 2.9 × length of metasternum. Fore femur moderately incrassate, flexor side with a row of ca. 13 dark, stiff setae, which are shorter than maximum width of femur; fore trochanter without such setae. Venter of pregenital abdomen ca. 0.4 × body length; sternum VII ca. 1.4 × length of two preceding sterna combined; posterior margin of sternum VII produced medially. Female genitalia small, but visible in lateral view.

Remarks.

Eotrechus sinensis is known from only the female holotype. The holotype was supposedly deposited at the U.S. National Museum of Natural History (Washington, D.C.), but we could not access this specimen for the present study. Andersen (1982: 19) suggested that this species was related to E. hygropetricus by a row of dark, stiff setae on the flexor side of the fore femur. However, this character state is also present in females of the E. pingae and E. petraeus species groups.

The type locality data of E. sinensis is exactly the same as that of one paratype of E. brevipes : "Fukien, East Gate, Kwangtseh Hsien" (see Andersen 1982: 17, 19). However, the female of E. brevipes can be easily distinguished from that of E. sinensis by the shape of the abdomen (in lateral view) and the fully concealed genitalia ( Andersen 1982). Eotrechus pingae is known from Guangdong, China and is nearest to the type locality of E. sinensis . Unfortunately, E. pingae is known only from a single male. Until males of E. sinensis are collected from its type locality, it is not possible to determine the relationship of this species to its congeners. Due to this uncertainty, this species is currently not assigned to any species group.

This species marks the easternmost limit of the known distribution of the genus Eotrechus .

Distribution.

China: Fujian ( Andersen 1982) (Fig. 25 ).

Undetermined species

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.