Brachinus (Metabrachinus) hexagrammus Chaudoir, 1876

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 : 583

Brachinus (Metabrachinus) hexagrammus Chaudoir, 1876

Fig. 1c

Brachinus hexagrammus Chaudoir, 1876: 55 ; Andrewes, 1930a: 49; Hrdlička, 2003: 215; 2017: 476

Type locality. India: Bengal, coll. Dr. Bacon.

Type depository. MNHN .

Specimens examined (n = 7). Syntype labelled “ Ind. Or. Bor. ’,coll. Dr. Bacon, det. Chaudoir ”; 5 specimens (2 males, 3 females) labelled “ India: Tamil Nadu: Ettimadai, Hand Picking, 08.IX.2015, coll. S.V. Akhil ”; 1 specimen labelled “ India: Gujarat: Anand , 17.XI.2017, coll. Thangavel ” .

Description. Length 8.5–9.5 mm. Head, pronotum and antennal segments 2–11 reddish brown; antennal segment one, legs and six spots on elytra yellowish red; pronotum with brownish black lateral margins; scutellum reddish brown; eyes and elytra black.

Head short, stout, rough, closely punctated, sparsely pubescent; neck highly wrinkled; eyes protruding; last segment of palpi narrowed and sub-truncate at apex; antennae short and stout, not reaching the middle of the elytra; length of antennal segment 3 equals the combined length of segments 1 and 2.

Pronotum broad, wider than long; disc laterally with anterior two-thirds convex, posterior third slightly divergent; hind angles pointed, sharp, but not protruding laterally; disc with surface highly punctated, wrinkled, pubescent with distantly placed setae; median groove shallow but visible in the mid region of disc, erased near to base and apex of pronotum.

Elytra broad, longer than wide, widest just before apex; scutellum pointed; humerus straight, corners rounded; apex straight, without re-entrant angle; striations broad, weak, shallow, rounded, clear towards base but faint towards apex, intervals shallow, narrow; surface highly punctated, densely pubescent; three yellowish red spots on each elytron, larger square shaped spot just below the humerus extending between the fourth and eighth striations, smaller, rounded spot just below the middle of elytra, oval shaped spot along the apical edge of elytra, not covering the apical edge.

Distribution. INDIA: Bengal; Gujarat: Anand; Tamil Nadu: Ettimadai; Arunachal Pradesh; Himachal Pradesh; Kashmir; Sikkim, Uttarpradesh. BHUTAN ( Hrdlička 2003, 2017). PAKISTAN ( Hrdlička 2003, 2017).

Figures

FIGURE 1. Dorsal habitus of Indian Brachinus species: a) B. dryas Andrewes, 1936 (holotype, BMNH); b) B. inops Andrewes, 1932 (holotype, BMNH); c) B. hexagrammus Chaudoir, 1876 (syntype, MNHN); d) B. sexmaculatus Dejean, 1825 (syntype, MNHN); e) B. tetracolon Chuadoir, 1876 (syntype, MNHN); f) B. tetragrammus Chaudoir, 1876 (syntype, MNHN); g) B. pictus (Hope, 1833) (ZSIM); h) B. cinctellus Chaudoir, 1876 (syntype, MNHN); i) B. eucosmus Andrewes, 1937 (holotype, BMNH)