Omolabus heterocerus (Sharp)

HAMILTON, ROBERT W., 2005, Omolabus Jekel in north and central America (Coleoptera: Attelabidae), Zootaxa 986 (1), pp. 1-60 : 44-45

Omolabus heterocerus (Sharp)

( Figs. 3 , 15 , 49, 50, 51 & 52) Attelabus heterocerus Sharp 1889: 5

Xestolabus heterocerus (Sharp) O’Brien & Wibmer 1982: 13

Type locality. Mexico, Guerrero

Type data. Two card mounted male syntypes with the following labels were examined: 1) male, Type [circular label with red margin], Amula, Guerrero, 6000 ft., Sept., H. H. Smith; BCA coll. IV. 3., Attelabus heterocerus Sharp ; Attelabus heterocerus , male type D. S. Mexico, Smith. 2) male, Chilpancingo, Guerrero, 4,600 ft., July, H. H. Smith [on card with specimen]; BCA coll. IV.3., Attelabus heterocerus Sharp [upside down]; Sharp Coll. 1905­3­13; Attelabus heterocerus Ind. Camp. D.S. The male from Amula is here designated as the lectotype.

Type holder. British Museum of Natural History ( BMNH)

Size range. Male 4.4 x 2.2 mm to 6.1 x 3.4 mm; Female 6.3 x 2.4 mm (one female only)

Description. Body black to brownish­black with orangish­red humeri. Head longer than wide, without punctures; frons concave, with weak median ridge; eyes reniform, moderately protuberant. Rostrum shorter than head, robustly enlarged beyond antennal insertions, width at apex nearly three times as wide as frons, dorsally beyond antennal insertions with moderately to densely punctured; punctures small; postlabial area in male with two short widely separated divergent blunt tipped spine­like projections. Antennae inserted near basal 1/4 of rostrum; club elongate­compact, subequal to funicle in length in male; basal and middle club segments long, subequal in length; terminal segment much shorter; funicular segment 1 ovo­globose, shorter than scape; segments 2­3 slightly longer, clavate, subequal in length; segment 4 same as 2–3 but shorter; segments 5­7 moniliform; segment 7 more robust than 5 and 6. Pronotum smooth, shiny, with minute punctures; lateral base with strigae and larger punctures; anterior collar weakly defined, dorsally widened and more or less v­shaped. Scutellum 1/3 wider than long, 4 sided, posterior margin broadly rounded. Elytra short, about as long as wide, widest at humeri; in dorsal view slightly narrowed from humeri to elytral apices, with weak transverse depression behind scutellum; humeri simple, rounded, moderately protuberant; striae small, widely spaced, becoming smaller and less distinct posteriorly; intervals, flat, smooth, wide, with numerous minute punctures. Profemora evenly swollen in both sexes.

Distribution ( Fig. 3 ). Most specimens examined, including Sharp’s type, are from the Mexican state of Guerrero. Specimens have also been taken in the Mexican states of Mexico and Colima.

Comments. This is the only species of Omolabus with a blackish body and large orangish­red humeral maculae (Figs. 49–52). The color pattern is like that of the North American Attelabus bipustulatus (Fabr.) but O. heterocerus has larger size and the male profemora are unarmed.

Host plants. Host plant association for this species is unknown.

Specimen data. 10 specimens were examined. The sexes and label data are as follows:

MEXICO: 1 male, Guerrero, 2.1 mi Northwest of Cacahuamilpa, 27­vii­1983, Kovarik, Harrison, & Schaffner; 1 male, Guerrero, 2.1 mi Northwest of Cacahuamilpa, 23­vii­ 1981, Bogar, Schaffner, & Friedlander; 1 male, Guerrero, 10.3 km NE Iguala, 5­vii­1987, 1280 m Acacia woodland 87­3, R. Anderson; 1 male, Guerrero, 17 mi E Tixtla, 11­vii­ 1985, Jones & Schaffner (TAMC); 1 male, Guerrero, hwy 95 9 km N El Ocotito, 7­vii­ 1980, ca. 1000' dec. forest/oak for. trans [deciduous forest/oak forest transition], Rifkind & Gum; 1 male, Mexico, 3 km SW Santa Tomas de los Platanos, 19­viii­1981, 1420 m, W. F. Barr (WFBM); 1 male, [ Mexico], Arroya Sta. Teresa [?], 18­vii­1981, G. Vogt (USNM); 1 female, Guerr. [Guerrero], 2 km S Ahuacatitlan, 20­ix­1989, 5,500', J. G. Wappes (CWOB); 1 male & 1 female, Col. [Colima], Colima, La Salada, 5­vii­2003, BTC, 19° 3'45"N, 103° 47'45"W, ex. plantas, J. Cortes­Aguilar (CZUG).

Figures

FIGURES 1 – 8. Distribution of Omolabus species: 1) Omolabus veracruensis (square), Omolabus spinipectus (circle), Omolabus megalomus (triangle), Omolabus fasciventris (open triangle) 2) Omolabus ligulatus (circle), Omolabus quadratus (open triangle) 3) Omolabus heterocerus (triangle), Omolabus angulipennis (circle) 4) Omolabus laesicollis 5) Omolabus corvinus 6) Omolabus sedatus (circle), Omolabus longiclava (triangle) 7) Omolabus callosus 8) Omolabus conicollis.

FIGURES 15 – 19. Male genitalia of Omolabus species, 64 X: a) tegmen, dorsal view b) median lobe with endophallic sac and transfer apparatus in repose, ventral view 15) Omolabus heterocerus, Mexico, Guerrero 16) Omolabus fasciventris, Panama, Canal Zone 17) Omolabus sedatus, Guatemala, Puente El Lobo­Puerto Barrios 18) Omolabus callosus, Tela­Leon Valley 19) Omolabus veracruensis, Mexico, Veracruz.