Badelina aterrima (Gory and Percheron, 1833)

Ratcliffe, Brett C., 2014, A Review Of The Neotropical Genera Badelina Thomson, 1880, Balsameda Thomson, 1880, Guatemalica Neervoort Van De Poll, 1886, And Heterocotinis Martínez, 1948 (Coleoptera: Scarabaeidae: Cetoniinae: Gymnetini), The Coleopterists Bulletin 68 (2), pp. 241-262 : 244-245

Badelina aterrima (Gory and Percheron, 1833) ( Figs. 1–4 )

Gymnetis aterrima Gory and Percheron 1833: 343 (original combination). Holotype male at MHNG, examined. Type locality: “ Brazil ”.

Description. Length 24.0– 27.8 mm; width across humeri 13.9–17.0 mm. Color black on dorsal surface; head, pronotum, and elytra velutinous. Venter an enamel grey to yellowish grey with black punctures. Head: Surface with punctures small to moderate in size and density. Clypeus with apex subtruncate to truncate, apex weakly reflexed. Eyes small, interocular width 6.0–6.5 transverse eye diameters. Antenna with 10 antennomeres, club distinctly longer than antennomeres 2–7 in both sexes. Pronotum: Surface sculpturing usually obscured by velutinous covering; when exposed, punctures small, sparse. Sides with slender mar- ginal bead, bead usually not reaching anterior or posterior angles. Elytra: Surface with sculpturing usually obscured by velutinous covering; when exposed, punctures small, sparse, becoming moderate in size and crescent-shaped behind weak apical umbones. Apices at suture subacutely produced. Pygidium: Surface in both sexes with transverse, vermiform strigae, setigerous; setae short, dense, tawny, occasionally all black. In lateral view, profile in males nearly flat in basal two-thirds, convex in apical third; surface in females weakly convex. Venter: Setae long, brown and black mixed, occasionally completely black. Mesometasternal process, in lateral view, protuberant, subparallel to ventral axis of body ( Fig. 2 ), apex rounded in ventral view. Abdominal ventrites 1–5 in both sexes nearly smooth in central third, lateral thirds with sparse, moderately large, crescentshaped punctures. Legs: Protibia slender, weakly tridentate in both sexes. Parameres ( Figs. 3–4 ): Form subrectangular in caudal view; apices broadly lanceolate, curving inwards, and with subapical, stout, spine-like tooth on lateral edge.

Distribution. Badelina aterrima is known from southern Brazil and Paraguay.

Locality Records. 58 specimens from BCRC, BMNH, CASC, CMNH, FMNH, MHNG, MLUH, MNHN, RMNH, UFRJ, USNM, and ZMHU. BRAZIL (57). RIO DE JANEIRO (18): Rio de Janeiro, No data. SÃO PAULO (1): No data. SANTA CATARINA (4): No data. NO DATA (34). PARAGUAY (1). Asunción (autonomous capital district) .

Temporal Distribution. January (2), February (1), March (1), October (1), November (3), December (1). Most specimens have little or no collecting data.

Diagnosis. Badelina aterrima is distinguished by a velutinous, totally black color on the pronotum and elytra ( Fig. 1 ). Badelina pygidialis has a brown pronotum and elytra, each with small, black spots ( Fig. 5 ). The parameres of B. aterrima and B. pygidialis are very similar ( Figs. 3–4 and 7–8 ), and so I debated whether B. aterrima was simply a melanistic phase of B. pygidialis . I believe that the two species are different in spite of the overall similarity of the parameres which, in many Gymnetini , are often not diagnostic anyway. Nevertheless, there are differences in the genitalia. In lateral view, the length of the basal piece is different between the two species. In B. aterrima , the basal piece is proportionately shorter, as measured against the length of the parameres, than in B. pygidialis ( Figs. 4 and 8 ). And in caudal view, the subapical spine on each paramere is much broader in B. aterrima than the slender spine seen in B. pygidialis ( Figs. 3 and 7 ). Furthermore, there are never any intergrades of body color or pattern as is usually seen in other gymnetine species that have melanistic morphs. I completely immersed several specimens of B. aterrima in ethanol for a lengthy period to see if there might be any underlying color or spot pattern typical of B. pygidialis that would become apparent upon being wetted, but there was nothing other than black. Because of the differences in the genitalia and the totally disparate color forms that have no intergrades, I maintain B. aterrima and B. pygidialis as two separate species.

Natural History. Nothing is known of the life history of these beetles. Ohaus (1900) reported young larvae of G. aterrima living in detritus in the earth near rotten tree stumps, and larger larvae were found inside the rotten stumps.

Figures

Figs. 1–4. Badelina aterrima. 1) Habitus; 2) Mesometasternal process, lateral view; 3–4) Parameres.

Figs. 5–8. Badelina pygidialis. 5) Habitus; 6) Mesometasternal process, lateral view; 7–8) Parameres.