Brachinus Bonelli 1810
Creators: name: Akhil, S. V.
name: Divya, M.
name: Sabu, K. Thomas
Publisher: name: Zenodo
Year: 2020
Subjects: Biodiversity
Taxonomy
Animalia
Arthropoda
Insecta
Coleoptera
Carabidae
Brachinus

description: Key to Indian species of Brachinus Bonelli, 1810   
1. Elytra with spots or transverse bands...................................................................... 2  
- Elytra without spots or transverse bands, monochrome black/bluish black/brownish black, only the suture sometimes reddish yellow............................................................................................. 12  
 2. Elytra yellow; three black markings of various shapes on elytra (Fig. 1g)................................... B. pictus   
- Elytra black/blue black/brown black; with reddish yellow spots or transverse band on elytra.......................... 3  
 3. Elytra with reddish yellow median transverse band and smaller triangular reddish yellow spot on the apex..... B. longipalpis   
- Elytra with only reddish yellow spots, without median transverse bands.......................................... 4  
4. Elytra with 6 distinct spots (3 on each elytron).............................................................. 5  
- Elytra with 4 spots (2 on each elytron)..................................................................... 8  
 5. Head and pronotum rough, densely punctated and pubescent with closely placed setae................... B. hexagrammus   
- Head and pronotum smooth, sparsely punctated, pubescent with widely spaced setae................................ 6  
 6. Pronotum longer than broad; elytra with reddish yellow lateral margin starting from the basal spot and continuing to apex, eventually forming an apical reddish yellow band................................................ B. sexmaculatus   
- Pronotum broader than long; elytra without reddish yellow lateral margin and apical band............................ 7  
 7. Elytral apex forming a re-entrant angle (Fig. 5a), elytral basal spot large, reaching the humerus; pronotum with basal margin broadly and lateral margin narrowly brownish black................................................. B. eucosmus   
 - Elytral apex rounded without forming a re-entrant angle (Fig. 5b), elytral basal spot small, not reaching the humerus; pronotum with apical, basal and lateral margins broadly black...................................................... B. reyi   
8. Pronotal apical margin with anterior lateral projection (Fig.5c)................................................. 9  
 - Pronotal apical margin without anterior lateral projection (Fig.5d)......................................... B. charis   
9. Elytra with reddish yellow lateral margin................................................................. 10  
- Elytra without reddish yellow lateral margin............................................................... 11  
 10. Pronotum densely punctated, pubescent with closely placed setae......................................... B. illotus   
 - Pronotum glabrous........................................................................... B. tetracolon   
 11. First spot on elytra aligned towards base, elytral apex not forming re-entrant angle (Fig. 5b)................... B. geiseri   
 - First spot on elytra placed in the midregion, elytral apex forming a strong re-entrant angle (Fig. 5a)........ B. tetragrammus   
12. Elytra unicoloured; suture same colour as the elytra......................................................... 13  
- Elytra bicoloured; suture reddish yellow.................................................................. 21  
 13. Head with two reddish yellow spots on frons.................................................. B. andamanensis   
- Head concoloured, without spots........................................................................ 14  
 14. Elytra blue-black............................................................................ B. pallidipes   
- Elytra pitch black/pitch brown.......................................................................... 15  
15. Pronotum and elytra punctated, pubescent................................................................. 16  
 - Pronotum and elytra smooth, glabrous........................................................ B. chaudoirianus   
16. Antennal segment 3 subequal to segments 1 and 2 combined.................................................. 17  
- Antennal segment 3 shorter than segments 1 and 2 combined.................................................. 20  
17. Pronotum concoloured................................................................................ 18  
- Pronotum bi-coloured................................................................................. 19  
 18. Pronotum dark brownish black with deep median groove deep, reaching the basal and apical margins; elytral apex rounded, not forming a re-entrant angle (Fig. 5b)................................................................ B. hazardi   
 - Pronotum reddish yellow with median groove shallow, not reaching the basal and apical margins; elytral apex straight, forming a re-entrant angle (Fig. 5a)......................................................................... B. inops   
 19. Pronotum with acute posterior angles (Fig. 5c, 5e), basal margin broadly brownish black; elytra convex........... B. dryas   
 - Pronotum with obtuse hind angles (Fig. 5d), both lateral and basal margins broadly brownish black; elytra subparallel............................................................................................... B. limbicollis   
 20. Pronotum rugose, punctate, median groove shallow; elytral striations weak............................... B. sordidus   
 - Pronotum smooth, sparsely punctate, median groove deep; elytral striations deep................ B. devagiriensis sp. nov.   
21. Elytral sutural line with narrow reddish yellow colouration................................................... 22  
- Elytral sutural line with broad reddish yellow colouration.................................................... 23  
 22. Antennal segment 3 subequal to segment 1 and 2 combined; pronotum longer than broad, median furrow deep, reaching the basal and apical margins; elytral apex forming faint re-entrant angle (Fig. 5a) with broad membranous border...................................................................................................... B. flaviventris   
 - Antennal segment 3 shorter than segment 1 and 2 combined; pronotum wider than long, median furrow shallow, not reaching the basal and apical margins; elytral apex not forming a re-entrant angle (Fig. 5b) but with a narrow membranous border................................................................................................ B. vigilans   
23. Elytra with reddish yellow lateral margins................................................................. 24  
- Elytra without reddish yellow lateral margins.............................................................. 27  
24. Antennal segments 1–2 reddish yellow, remainder brownish, segment 3 subequal to segments 1 and 2 combined......... 25  
- Antennal segments 1–4 reddish yellow, remainder brownish, segment 3 shorter than segments 1 and 2 combined........ 26  
 25. Elytra brownish black.......................................................................... B. limbellus   
 - Elytra black................................................................................. B. cinctellus   
 26. Pronotum length equal to width, base straight................................................... B. pokharaensis   
 - Pronotum longer than broad, base bisinuate.......................................................... B. stevensi   
 27. Pronotum with hind angles pointed, at right angles (Fig. 5f)........................................... B. suturellus   
- Pronotum with hind angles blunt, obtuse (Fig. 5d).......................................................... 28  
 28. Pronotum disc with posterior fourth parallel, hind angles slightly obtuse.................................. B. peltastes   
 - Pronotum disc with posterior fourth divergent, hind angles very obtuse.................................. B. modestus
description: Published as part of Akhil, S. V., Divya, M. & Sabu, K. Thomas, 2020, Bombardier beetles of genus Brachinus Weber, 1801 (Carabidae: Brachininae Brachinini) from India, pp. 576-600 in Zootaxa 4816 (4) on pages 577-578, DOI: 10.11646/zootaxa.4816.4.7, http://zenodo.org/record/3954685