Tiarocera Burmeister, 1842

Ratcliffe, Brett C., 2014, A Review of the Neotropical GeneraAstroscaraSchürhoff, 1937, ChiriquibiaBates, 1889, HadrostictaKraatz, 1892, JansoniaSchürhoff, 1937, MacrocraniusSchürhoff, 1935, andTiaroceraBurmeister, 1842 (Coleoptera: Scarabaeidae: Cetoniinae: Gymnetini), The Coleopterists Bulletin 68 (3), pp. 363-376 : 373

Tiarocera Burmeister, 1842

Tiarocera Burmeister 1842: 248 . Type species: Gymnetis cornuta Gory and Percheron, 1833: 69 , here designated. Burmeister (1842) included two species in Tiarocera : Gymnetis rhinoceros Gory and Percheron and G. cornuta . He did not designate a type species for the genus, and I do so here by subsequent designation. Chapin (1932) “supposed” the first species listed in Burmeister, G. rhinoceros , was the type, but Chapin did not make a designation. Following recommendation 69A. 3 in the rules of nomenclature regarding remaining species in a genus after removal of others, G. cornuta is the only remaining species in the genus, since I am removing G. rhinoceros to Allorrhina .

Description. Form elongate, subparallel, robust, slightly dorsoventrally flattened. Length 17–25 mm. Color black, shiny. Head: Frons with longitudinal, narrow, forward projecting horn (majors) or keel (minors and females); sides of horn/keel with moderately long, reddish brown setae. Clypeus subquadrate, sides rounded, apex with long, bifurcate (majors) or short, truncate (minors and females) horn projecting upwards and forward; base of horn on either side with moderately long, reddish brown setae. Eyes small, interocular width equals 8.0 transverse eye diameters. Antenna with 10 antennomeres, club subequal in length to antennomeres 2–7. Pronotum: Subtrapezoidal, widest near base, gradually convergent to anterior angles, basomedian lobe strongly produced posteriorly, lobe covering all but tip of scutellum. Sides with nearly completae marginal bead. Females on anterior margin at center with tubercle followed by shallow fovea. Elytra: Widest at base, posthumeral emargination distinct. Bead present on lateral margins. Surface with punctate striae on disc, punctres becoming smaller and sparser on sides. Pygidium: Surface concentricallty strigulose, with short, reddish brown setae. Venter: Mesometasternal process, in lateral view, barely protuberant, subparallel to ventral axis of body ( Fig. 27 ). In ventral view, process subparallel, with broadly rounded apex. Legs: Males with protibia relatively slender, strongly tridentate; protibia broader in females. Parameres ( Figs. 29–30 ): In caudal view, form subrectangular, elongate, apices broadly rounded with small, subapical tooth on lateral edge.

Figures

Figs. 26–27. Tiarocera cornuta, habitus. 26) Male;

Figs. 28–31. Tiarocera cornuta. 28–29) Lateral and ventral views, respectively, of form of mesometasternal process; 30–31) Parameres.