Balgus rugosus ( Blanchard, 1843 )

Barbosa, Felipe Francisco, 2016, Revision and phylogeny of the genus Balgus Fleutiaux, 1920 (Coleoptera, Elateridae, Thylacosterninae), Zootaxa 4083 (4), pp. 451-482 : 463-466

Balgus rugosus ( Blanchard, 1843)

( Figure 7 )

Pterotarsus rugosus Blanchard, 1843: 146 , 147 (original description); Guérin-Méneville, 1843: 196; Bonvouloir, 1875: 832, 845 (redescription).

Balgus rugosus Fleutiaux, 1920: 97 (new combination); Schenkling, 1928: 7 (catalogue); Blackwelder, 1944: 275 (catalogue); Chassain & Touroult, 2010: 21 (catalogue); Chassain & Touroult, 2013: 78, 79, 81 (redescription, aedeagus described).

Diagnosis. Cylindrical body ( Figures 7A, B, C, F ); dorsal and ventral regions covered with very thick, yellow or golden pubescence on the head, antennae, apex and base of pronotum, scutellum, elytral base next to the scutellum, legs and the more apical region of the abdomen; basal fifth of elytra with five elevated stria and with rough granulation, these five elevated stria remained high throughout the length of the elytra, but without rough granulation; elytra without tubercles.

Redescription. Cylindrical body, narrowing attenuate on posterior fifth. Elytra about two and a half times as long as pronotum. Dorsal and ventral region covered with thick yellow or golden pubescence on head, antennae, apex and base of pronotum, scutellum, elytral basal next to scutellum, legs and more apical region of the abdomen.

Color: Dark brown, except: antennal rami and tarsi yellow. Elytra with two yellow bands: basal band discontinuous, originates in middle of elytra, just above elytral margin, somewhat apically then bends towards the base, sinuous to the suture; apical band wider, originates just above elytral margin, extending apically and dorsally to the suture.

Head ( Figure 7D ): Densely punctate, with deep longitudinal median anterior depression, continues posteriorly on longitudinal groove on vertex, not V-shaped. Eye with spherical surface in lateral view, dorsal margin not sinuous.

Thorax: Subcylindrical prothorax ( Figures 7A, B, C, F ), almost as long as wide; margins subparallel; posterior angle subacuminate; tubercles short, conspicuous; posterior half of pronotum with posterolateral oblong tubercle, posterolateral rounded tubercle and posteromedian rounded tubercle; anterior half of the pronotum with anterolateral oblong tubercle, anterolateral rounded tubercle and anteromedian rounded tubercle. Pronotal sculpture formed by deep and rough punctations. Scutellum rounded; little longer than wide, not carinate. Lateral thoracic sclerites hidden under elytra. Antennal acetabulum very deep next to prosternal process. Prosternal process gradually attenuate towards posterior margin; margin more or less rounded. Prosternum, mesoventrite and metaventrite densely punctate. Elytra ( Figures 7A, C, F ) densely punctated; apex subacuminate; a fifth of elytra with five elevated stria and with rough granulation, these five elevated stria remain high throughout length of elytra, but without rough granulation; first stria merges with second and fourth with fifth near apical fifth of elytra; without tubercles.

Abdominal ventrites: Finely punctate; ventrite 5 ( Figure 7E ) triangular, with longitudinal median carina forming a large tooth, gradually narrowed from base to apex, which is truncated, not curved.

Female genitalia ( Figure 7G ): Baculum about 6 times as long as the coxite; baculi, separated by about width of baculum, at least in apical third. Coxites without setae.

Aedeagus: Paramere tapering as it approximates apex; acuminate at apex and with many setae. Penis tapering to apex; acuminate at apex, slightly curved ventrally in lateral view. Phallobasis approximately three times as long as paramere; about three times paramere width. Concavity of phallobasis in dorsal view limited to the base of the phallobasis (based on Chassain & Touroult, 2013).

Intraspecific variation: Size variation (N = 25): length 11.30–16.90 mm (mean = 14.14 mm); humeral width 2.90–5 mm (mean = 3.98 mm). Some specimens have one or two very small teeth after the large tooth on the longitudinal median carina of ventrite 5.

Comparative notes: Inside the genus, this is the only species with dense pubescence. Even when the pattern of pronotal tubercles of B. albofasciatus and B. rugosus are similar to the pattern of pronotal tubercles of B. tuberculosus , B. eganensis , B. humilis and B. obconicus , the tubercles are significantly less protruding in the first two species in relation to other four species.

Etymology. [rugo+adjective suffix that indicates abundance]. rugo, from Latin, “rugosities”.

Material examined. 1 ex., Holotype, Bolivia, [Santa Cruz de la Sierra, bord du Rio Piray, au milieu du Monte- Grande - information in in the original description, but absent in the labeling], Voy d'Orb., Pl. 8, f B., Guérin- Méneville coll., IRSN; 1 ex., Belize, Chiquibul Forest Res., Las Cuevas field station, 16°44'N, 88°59'W, 500–700 m, D. Inward, 2005-78, BNHM; 2 exs., Bolivia, Santa Cruz, Reserva Privada Potrerillo del Guendá, Snake Farm, 17°40'26"S, 63°27'44"W, 400 m, 9–28/XI/2006, B. K. Dozier coll., FDACS; 2 exs., Bolivia, Santa Cruz, Santiago de Chiquitos, 700, XI/1959, F. W. Waltz col., I.G.: 22.353, IRSN; 1 ex., Bolivia, Santa Cruz, Potrerillo del Guendá, Snake Farm, 17°40'S, 63°27'W, 400 m, 24- 9-28/XI/2006, Dozier coll., FDACS; 1 ex., Bolivia, Santa Cruz, Potrerillo del Guendá, Snake Farm, 17°40'S, 63°27'W, 370–400 m, 24–25/XI/2011, “Walco” J. Romero col., FDACS; 10 exs., Bolivia, Santa Cruz, Potrerillos del Guendá, 40 km NW Santa Cruz de la Sierra, 17°40'26"S, 63°27'44"W, 5–20/XI/2004, B. K. Dozier col., black light trap., FDACS; 3 exs., Bolivia, Santa Cruz, 3,7 km SSE Buena Vista, Hotel Flora & Fauna, 430m, 15–22/XI/2001, B. K. Dozier coll., black light trap, Tropical transition forest, FDACS; 1 ex., Brazil, Bahia (BA), Encruzilhada, Motel da Divisa, Rodovia Rio-Bahia, Km 965, 960 m, Seabra & Roppa cols., XI/1971, MZUSP; 1 ex., Brazil, Espírito Santo (ES), Linhares, M. Morais col., X/1969, MZUSP; 1 ex., Brazil, Espírito Santo (ES), Linhares, P. C. Elias col., XI/1972, MZUSP; 1 ex., Brazil, Espírito Santo (ES), Rio (illegible), 16/XI/19 (illegible), F, Hoffmann col., MNRJ; 2 exs., Brazil, Goiás, Campinaçu, Vale do Bijuí, Reserva de Mata nativa/Plantio 18, Aguiar col., UFRJ; 4 exs., Brazil, Goiás (GO), Jataí, IX– XI/1997, E. Fleutiaux coll., MNHN; 1 ex., Brazil, Goiás (GO), Jataí, F. M. Oliveira col., IX/1974, C. A. Campos Seabra coll., MZUSP; 1 ex., Brazil, Goiás (GO), Jataí, J. D. Fry coll. 1905.100, IX– XI/1897, E. Fleutiaux, det., BNHM; 1 ex., Brazil, Goiás (GO), Jataí, J. D. Fry coll. 1905.100, IX– XI/1897, BNHM; 1 ex., Brazil, Goiás (GO), Jataí, M. Alvarenga col., XI/1972, A. Cobos det., 1973, MZUSP; 2 exs., Brazil, Goiás (GO), Rio Verde, A. Sicard coll., MNHN; 2 exs., Brazil, Goiás (GO), E. Gounelle coll., MNHN; 1 ex., Brazil, Goiás (GO), E. Fleutiaux det., E. Gounelle coll., MNHN; 1 ex., Brazil, Goiás (GO), E. Fleutiaux coll., MNHN; 1 ex., Brazil, Mato Grosso do Sul (MS), Colorumbá, Serra do Urucum, K. Lenko col., 23/XI/1960, P. Pereira det., 1964, MZUSP; 1 ex., Brazil, Paraná (PR), Rolândia, R. von Diringshoffen col., X/1945, MZUSP; 1 ex., Brazil, Rondônia (RO), 62 Km SW., Ariquemes, nr. Fazenda Rancho Grande, 4–16/XI/1997, J. E. Eger col., black light trap, FDACS; 1 ex., Brazil, Rio de Janeiro (RJ), Rio de Janeiro, BR-465, Antiga Estrada (ou Rodovia) Rio-São Paulo, km 7 (antigo km 47) - Universidade Federal Rural do Rio de Janeiro - UFRuralRJ (anteriormente UFRRJ), D. Braga, 28/I/1944, MNRJ; 1 ex., Brazil, Santa Catarina (SC), Itapema, J. Carlos col., I/1995, FIOCRUZ; 1 ex., Brazil, Santa Catarina (SC), Joinville, R. von Diringshoffen col., II/1954, MZUSP; 1 ex., Brazil, E. Gounelle coll., E. Fleutiaux det., MNHN; 3 exs., Brazil, E. Gounelle coll., MNHN; 1 ex., Brazil, A. Sicard coll., E. Fleutiaux det., MNHN; 1 ex., Colombia, E. Fleutiaux coll., MNHN; 1 ex., French Guiana, Migne des Chevaux, RN2 PK22 Roura, 16/XI/2008, SEAG, J. Chassain det., 2009, I. R. Sc. N. B. coll., Don J. Chassain, I.G.: 31.315, IRSN; 1 ex., Mexico, Chiapas, Motozintia, Finca de la Victoria, M. A. Vulcano col., 6/X/1962, MZUSP; 1 ex., Panama, Chiriquí, Bugaba, 800–1500 ft., Champion col., J. Muona det., 1982, BNHM; 1 ex., Panama, Chiriquí, V. de Chiriquí, 3–4000 ft., Champion col., BNHM; 1 ex., Trinidad & Tobago, Trinidad, Caparo, A. Heyne & Berlin-Wilm., E. Fleutiaux coll., MNHN.

Distribution. Belize, Bolivia, Brazil (BA, ES, GO, MS, PR, RO, RJ & SC), Colombia, French Guiana, Mexico, Panama and Trinidad & Tobago ( Figure 14 ).

Type locality. Bolivia, Santa Cruz de la Sierra, bord du Rio Piray, au milieu du Monte-Grande ( Bolivia, Santa Cruz de la Sierra, edge of Rio Piray, on Monte-Grande).

Figures

FIGURE 7. Balgus rugosus (Blanchard, 1843): A) habitus, dorsal view; B) habitus, ventral view; C) habitus, lateral view; D) head, frontal view; E) ventrite 5, ventral view; F) pronotum and elytra, dorsal view; G) female genitalia, dorsal view, apex oriented to the bottom of the page. Genitalia scales: 0.5 mm, other scales: 2 mm.

FIGURE 14. Geographical distribution of Balgus rugosus (Blanchard, 1843).