Zethus (Zethastrum) dolosus Bingham 1897

Yeh, Wen-Chi & Barthélémy, Christophe, 2023, A taxonomic study on the genus Zethus Fabricius from Hong Kong, with proposal of a new synonym (Hymenoptera: Vespidae: Eumeninae), Zootaxa 5339 (6), pp. 520-532 : 522-529

Zethus (Zethastrum) dolosus Bingham 1897

Zethus dolosus Bingham, 1897: 332 (key), 333—“ Burma (Pegu Hills), Tenasserim ” (holotype, ♀, NHMUK).

Material examined. CHINA — Hong Kong • 1♁; Hok Tau; 22°29’25.31”N, 114°11’0.14”E; W.-C. Yeh leg.; hand net; 06 Jun. 2006 ( FACT) .

MYANMAR — Tenasserim • 1♀; Haundraw Valley ; Aug, 1894; Coll. Bingham; ( MSNVE) • 1♀; Carin Cheba (= Karen Hills); 900–1000 m; L. Fea leg.; 05 Dec. 1888; Giordani Soika det., 1939; ( MSNVE) • 1♀; Shwegyin ; Nov. 1892; Coll. Bingham; Giordani Soika det.; ( MSNVE) .

VIETNAM — Tonkin • 1♀; Hoa-Binh; 1927; A. De. Cooman leg.; Giordani Soika det., 1966; ( MSNVE) .

Diagnostic description. Female ( Figs 12–17 ). Body black, antennal flagellomeres and legs dark reddish brown, tegula dark brown, wings brownish tinted. Body adorned with long whitish hairs, much longer and denser on clypeus. Lateral side of pronotum densely and deeply macropunctate on upper half and broadly costate on lower half. Propodeum coriaceous and dull, posterior depression broadly costate, lateral side coarsely foveate on upper half and broadly costate on lower half ( Fig. 12 ). Clypeus narrowly truncate apically with two tiny lateral teeth, inter-antennal area broadly produced and visible in dorsal view ( Fig. 13 ). Tegula broadly oval with posterior lobe incurved and pointed, inner margin roundly protruding at middle ( Fig. 15 ). Propodeum with lateral carina weak, submedian carina strong at basal 3/5 of propodeum, and bf short elliptical (Fig. 16). Metasoma with Sg1 about as long as both mesosoma and Sg2 ( Fig. 14 ); Sg2 distinctly petiolate with S2 distinctly angulately curved at basal 2/5 ( Fig. 17 ).

Male ( Fig. 18–21 ). Differing from female in the following: Clypeus almost entirely covered by a large inverted and sub-triangular yellow spot, mandibles with broad yellow stripes ( Fig. 18 ). Ocelli larger with diameter around 1/3 of the distance between compound eyes and lateral ocelli ( Fig. 19 ). Antennal flagellomeres darker, F11 slightly curved and bullet-shaped in ventral view ( Fig. 20 ), apex rounded and reaching the base of F 8 in appressed condition ( Fig. 21 ).

Remarks: Lee (1985) reported the first record of Z. dolosus from Guangdong in China, but the female he described and illustrated cannot be confirmed as being of that species; indeed, the important diagnostic feature of Z. dolosus , the angulate contour of S2, was not mentioned. Lee mentioned that the body hairs were mainly brownish and the dorsal side of propodeum was coarsely and densely punctate, both features do not correspond well to those of Z. dolosus , in which hairs are whitish and the dorsal side of propodeum is mainly coriaceous with only few punctures.

Distribution: India, Myanmar, Thailand ( Gusenleitner, 1988), Vietnam, China ( Hong Kong, Guangdong?).

Figures

FIGURES 12–15. Zethus dolosus, female. 12, propodeum in lateral view; 13, head in dorsal view; 14, metasoma in dorsal view; 15, tegula; 16, propodeum in dorsal view.

FIGURES 17–21. Zethus dolosus, 17, female; 18–21, male. 17, lateral habitus; 18, head in frontal view; 19, head in dorsal view; 20 & 21, male antenna.