Pheropsophus hilaris (Fabricius, 1798)

Venugopal, Akhil S. & Thomas, Sabu K., 2019, Bombardier beetles of the genus Pheropsophus Solier 1833 (Carabidae: Brachininae: Brachinini) from Indian subcontinent, Zootaxa 4608 (1), pp. 65-89 : 72-73

Pheropsophus hilaris ( FABRICIUS, 1798)

( Fig. 3 A, 3 B, 3 C, 3 D, 3 E )

= Brachinus discicollis DEJEAN 1825

= Brachinus affinis DEJEAN 1825

Carabus hilaris Fabricius, 1798: 56 ; Schaum, 1847: 49; Motschulsky, 1855: 55; Chaudoir, 1876: 25; Gestro, 1882: 297; Bates, 1892b: 391; Arrow, 1901: 202; Andrewes, 1921a: 159; 1924a: 55; 1930: 272; Jedlička, 1963: 529.

Brachinus discicollis Dejean, 1825: 300 ; Chaudoir, 1876: 21; Arrow, 1901: 203; Andrewes, 1930: 272.

Brachinus affinis Dejean, 1825: 301 ; Andrewes, 1930: 272.

Specimens examined (n=11): Lectotype (here designated), in India orientali, Daldorff, Mus. D. Lund “, type in ZMUK ; Paralectotypes (2 specimens) (here designated), “ India orientali”, type in ZMUK

Other specimens examined: 1 ex., “in India Orient. Dejean. ” (in MNHN) ; 1 ex. „Ost-Indien / Trichinopoly / T. Paesler G.“ (labelled as P. discicollis ) (in ZMHB) ; 1 ex. “ India Oriental. Dejean.” (in ZMHB. Nr. 2368) ; 1 ex. „South India / Madras State / Coimbatore / 1400 F“ (in ZMHB) ; 4 exs., India: Tamil Nadu: Coimbatore ( TNAU) .

Description. Length: 13.0–16.0 mm; TW: 5.6 mm

Colour: Head yellowish anteriorly and brownish red posteriorly, a black spot in the middle of the brownish red portion; pronotum brownish black with reddish brown oval spots on both sides of the middle furrow (but not extending to the lateral margin in some variations), posterior and anterior margins of pronotum black/brownish-black, cordiform reddish brown spot on pronotum with wing like colour projection laterally (absent in some variations); elytra black; elytral apex with moderate yellow band; legs with coxa, trochanter, femur and tibia reddish yellow; 1 st tarsi with middle region reddish yellow and borders brown; rest of the tarsi brown coloured; claws brownish black; ventral side of head reddish yellow; prosternum brownish black with light reddish yellow coloured prosternal process; rest of the ventral region brownish black.

Head: Elongated, longer than broad; neck wrinkled; eyes protruding; first four antennal segments bright.

Pronotum: Convex anteriorly and narrowed posteriorly; lateral bead present, narrow; median furrow distinct.

Elytra: Convex, narrower at the base, widest just before apex; humerus obliterate, base rounded; the median transverse band somewhat strongly serrated on its edges (the marking almost touches the apical band in some variations), apex with sharp, broad yellow band.

Geographical distribution. INDIA: Maharashtra: Nagpur ( Andrewes 1930). Deccan ( Chaudoir 1876); Tamil Nadu: Chennai, Thiruchirappalli (Thichinopoly), Redhills, Coimbatore ( Andrewes 1930); Pondicherry ( Andrewes 1930); SRI LANKA: Murunkan, Anuradhapura ( Andrewes 1930); BANGLADESH ( Andrewes 1930). CHINA ( Jedlička 1963)

Remarks. Pheropsophus hilaris is morphologically similar to P. catoirei , but distinct by basic colour of pronotum black with heart-shaped reddish brown mark, elytra convex with obliterate humerus, smaller elytral humeral spot.

Pheropsophus hilaris is the most confused Indian Pheropsophus species due to difficulties with its taxonomy following the misplacement of the type species during 1798–1920 period, later workers who were not referring to the notes of Andrewes (1921a) regarding the misplacement of type species and the misinterpretation of the very brief description provided by Fabricius (1798). It led to the split of the species in two subspecies— P. hilaris hilaris and P. hilaris sobrinus , both of which are actually variants of P. sobrinus (see reinstating the species status of P. sobrinus ).

Pheropsophus hilaris was first described by Fabricius (1798) and the type was presumed to be kept at Copenhagen museum. Andrewes (1921a) specifically mentioned that “the original type species at Copenhagen (now at ZMUK) is having a misplaced label and it does not agree with the description of P. hilaris rather it resembles P. tripustulatus described by Fabricius itself; the type is ignored and the description accepted”. However, the type was not ignored and P. tripustulatus was maintained as the type for P. hilaris . This error was noticed during the revision of the description of P. hilaris , P. discicollis and P. tripustulatus while analysing the type species. Analysing the type of P. hilaris at Copenhagen museum (as per Andrewes, 1921a) it was found that Andrewes was correct in his statement on misplaced type and what was kept labelled as type of P. hilaris at Copenhagen was actually P. tripustulatus . Authors could trace the three P. hilaris specimens from the Fabrician collection preserved at Kiel museum, which exactly matched the type description of P. hilaris by Fabricius 1798. One of them is designated as lectotype ( Fig. 3 A ), and the others as paralectotypes ( Fig. 3 B ).

Analysis of the types of P. hilaris ( Fabricius 1798) and P. discicollis ( Dejean 1826) (3C, 3D, 3E) showed that these two species are conspecific having exactly similar morphological characters. This error might have happened probably because Dejean (1826) did not see the holotype of P. hilaris described by Fabricius (1798). Pheropsophus hilaris , being the older name among the two, is retained.

Figures

FIGURE 3. Dorsal habitus of A) Pheropsophus hilaris (Lectotype, ‘Ind.Or.’, ZMUK), B) P. hilaris (Paralectotype, ‘Ind. Or.’, ZMUK), C) P. discicollis (‘Ind. Or.’, MNHN), D) P. discicollis (‘Coimbatore’, ZMHB), E) P. discicollis (‘Ind. Or.’, ZMHB), F) P. sobrinus (Holotype, ‘Ind. Or.’, MNHN), G) P. sobrinus (Verified specimen, ‘India’, BMNH), H) P. sobrinus (Verified specimen, ‘India’, NHMW), I) P. tripustulatus (Verified specimen, ‘locality unknown’, ZMUK)