Brachinus (Brachynidius) modestus Schmidt-Göbel, 1846

Akhil, S. V., Divya, M. & Sabu, K. Thomas, 2020, Bombardier beetles of genus Brachinus Weber, 1801 (Carabidae: Brachininae Brachinini) from India, Zootaxa 4816 (4), pp. 576-600 : 586

Brachinus (Brachynidius) modestus Schmidt-Göbel, 1846

Fig. 2f

Brachinus modestus Schmidt-Göbel, 1846: 73 ; Chaudoir, 1876: 69; Bates, 1892: 396; Andrewes, 1923: 42; 1930a: 50; Saha, 1992: 51; Hrdlička, 2017: 477.

Type locality. India: Bengal : Kolkata .

Type depository. NMPC .

Specimen examined (n=1). Type labelled: “Bengal”.

Description. Length 5.2 mm. Head, pronotum, legs, sutural line, antennal segments, palpi, scutellum and region around scutellum reddish brown; eyes grey; elytra brownish black.

Head stout, broad, wider than long, punctated, pubescent; vertex smooth, glabrous, frons, region around eyes and neck punctated, pubescent; eyes protruding; frontal foveae deep; antennal segments stout, short, not reaching the middle of the elytra, segment 3 shorter than segment 1.

Pronotum slightly broader than long, punctated, densely pubescent; disc with apical margin straight, lateral region of apical margin not projecting forward, basal margin slightly sinuated outward; disc laterally with anterior three-fourths convex, posterior fourth divergent, hind angle obtuse, blunt, projecting laterally; median groove deep reaching both apical and basal margin; lateral bead narrow, dark brown.

Elytra subparallel, punctated, densely pubescent, with golden brown setae; base narrow, rounded, humerus erased; apex without a re-entrant angle; scutellum very small, pointed; striations weak, rounded, intervals narrow, setae covering both striations and intervals; sutural colour extending till middle of elytra, widest near base where it extends between 1st and 3rd striae, narrowing gradually towards apex.

Distribution. INDIA: Bengal: Kolkata. MYANMAR: Tharrawaddy. Prome. Toungoo. Rangoon. Moulmein. VIETNAM: Cochinchina. CHINA: Fujiyan ( Hrdlička, 2017).

Remarks. Comparison of the type specimens of B. modestus Schmidt-Göbel, 1846 , B. peltastes Andrewes, 1931 and B. suturellus Chaudoir, 1876 shows that there is no significant variation between the three species other than the colour (elytra black in B. suturellus , pitch black in B. peltastes and brownish black in B. modestus ) and size (5.2 mm in B. modestus , 6.0 mm in B. peltastes and 8.5 mm in B. suturellus ). We have not synonymised Brachinus suturellus and B. peltastes with B. modestus as we are not certain how far the colour of the types have faded.

Figures

FIGURE 2. Dorsal habitus of Indian Brachinus species (cont.): a) B. flaviventris Chaudoir, 1876 (syntype, MNHN); b) B. hazardi Andrewes, 1930 (holotype, BMNH); c) B. illotus Chaudoir, 1876 (syntype, MNHN); d) B. limbellus Chaudoir, 1876 (syntype, MNHN); e) B. limbicollis Chuadoir, 1876 (syntype, MNHN); f) B. modestus Schmidt-Göbel, 1846 (holotype, NMPC); g) B. peltastes Andrewes, 1931 (holotype, BMNH); h) B. reyi Andrewes, 1924 (holotype, BMNH); i) B. sordidus Andrewes, 1933 (holotype, BMNH)