Aegopsis bolboceridus ( Thomson, 1860 )

Sobral, Rafael, Grossi, Paschoal C. & De Morais, José W., 2018, Two new species of Aegopsis Burmeister, 1847 (Coleoptera: Scarabaeidae: Dynastinae) from the central Brazilian Cerrado, Zootaxa 4526 (2), pp. 175-194 : 177-183

Aegopsis bolboceridus ( Thomson, 1860)

( Figs. 1–8 , 11 )

Agacephala bolbocerida: Thomson 1860: 19 ; Endrödi 1970: 52; Endrödi 1985: 213.

Brachysiderus bolbocerida: Prell 1934: 58 ; Blackwelder 1944: 260.

Aegopsis bolboceridus: Dechambre & Grossi 1990: 239 ; Lachaume 1992: 28; Dechambre 1999: 174; Oliveira et al. 2008: 324; Oliveira & Frizzas 2013: 1; Neita-Moreno et al. 2014: 114.

Diagnosis. Males: clypeus subrectangular, apex emarginate ( Fig. 2A ); internal lobe of mandibles apically protruding, mesal brush covering internal lobe laterally ( Fig. 5A ); mandibles with apical protuberance near external carina ( Fig. 5A ); mentum subrectangular, carina on mentum absent ( Fig. 5D ); labrum concave at middle ( Fig. 4A ); parameres, in lateral view, thinner than apex of phallobase, lateral carina slightly curved basally ( Fig. 6A ). Females: clypeus round, punctures shallow and annular on vertex ( Fig. 7A ); distance from canthi carina to canthi apex almost equal to canthi thickness ( Fig. 3B ); sensorial area of maxillary palpus striate ( Fig. 4C ).

Male redescription. Color: Surface lustrous; dorsum, venter, and appendages brown with weak metallic shine ( Fig. 1A ). Head: Frons moderately punctate; punctures moderate and small, mixed. Cephalic horns moderately punctate, weakly rugopunctate dorsally on outer side; punctures sparse and small. Clypeus moderately punctate, punctures coalescent basally, becoming sparser and smaller to apex; shape subrectangular, apex truncate ( Fig. 2A ); clypeus strongly concave from frontoclypeal suture to apex. Ocular canthi straight anteriorly, posteriorly projecting, tip round; anterior canthi carina sinuous, apex inconspicuous near external edge of canthi ( Fig. 3A ). Mouthparts: Labrum setose, concave at middle, sides round ( Fig. 4A ). Mandibles subtriangular with two prominent teeth apically and two ventral carinae; in ventral view, apical protuberance near external carina, internal lobe apically protruding, mesal brush covering internal lobe laterally ( Fig. 5A ). Maxilla with galea subtriangular, teeth absent; maxillary palpomere IV 3.6 times longer than wide; sensorial area densely striated ( Fig. 4B ). Mentum subrectangular, sides strongly convex, carina absent ( Fig. 5D ). Prothorax: Pronotum bordered, disc weakly convex and distinctly punctate. Thoracic horn strong, apex slightly downturned. Puncture size almost uniform on disc, becoming smaller towards thoracic horn apex and denser on sides ( Fig. 2B ). Anterior angles and lateral edges of horn completely wrinkled. Scutellum: Subtriangular in shape, apex weakly projected; punctures large and dense medially and apically, small basally. Elytra: Form 1.7 times longer than wide. Surface glabrous, densely covered by large ocellate punctures and fine annular punctures, microsculpture slightly wrinkled. Elytral punctures generally irregular, with distinct sutural striae; striae not impressed, punctures small. Humeral umbone weak, apical umbone distinct not crossing elytral external edges in dorsal view. Legs: Protibial surface punctate dorsally, with two setose striae. Protibia with three well-developed external teeth posteriorly decreasing in size. Pygidium : Form 2.6 times wider than long, strongly convex. Disc and posterior edge glabrous, hirsute laterally, densely wrinkled on edges, larger and denser punctures medially. Genitalia: Parameres, in dorsal view, as in Fig. 6C ; in lateral view, thinner than apex of phallobase, lateral carina slightly curved at base ( Fig. 6A ); in ventral view, apex round, ventral carina basally acute, inferior edge of parameres concave ( Fig. 6B ).

Variation, males. Major males with cephalic horns about 2–4 times longer than vertex; body length 25.4–34.8 mm (n = 53) and pronotal width 12.1–15.5 mm (n = 53), as measured from the apex of the cephalic horns to the apices of the elytra; ocular canthi sometimes posteriorly shorter. Minor males ( Fig. 1B ) with cephalic horns smaller or as long as vertex and frons together; body length 17.9–22.6 mm (n = 14) and pronotal width 9.2–11.6 mm (n = 14); thoracic horn short, tuberculate, not crossing anterior margin of pronotum nor crossing vertex; ocular canthi subtriangular, carina more notable; punctures of pronotum larger and stronger; parameres shorter and broader.

Measurements. Body length: 17.9–34.8 mm. Cephalic horns length: 1.2–8.1 mm. Elytral length: 11.4–18.5 mm. Elytral width: 6.8–10.6 mm. Pronotal width: 9.2–15.5 mm. Protibial length: 4.8–9.8 mm.

Females. Females are as males in general aspect, except the following ( Fig. 1C ). Head: Cephalic horns absent; frons with two inconspicuous tubercles ( Fig. 7B ); clypeus round, slightly concave from frontoclypeal suture to apex, punctures larger and denser, especially on clypeus, wrinkles in front of the tubercles ( Fig. 7A ); punctures shallow and annular on vertex. Ocular canthi convex anteriorly, concave posteriorly, tip round; distance from canthi carina to canthi apex almost equal to canthi thickness ( Fig. 3B ). Mouthparts: Labrum convex anteriorly, sides more round. Mandibles and teeth shorter, internal lobe more protruding, mesal brush sparsely covering the internal lobe ( Fig. 8A ). Maxilla with stipes less hirsute, maxillary palpomere IV three times longer than wide, sensorial area shorter, striae sparser and distinct ( Fig. 4C ). Mentum shorter, more hirsute on apex ( Fig. 8D ).

Pronotum: Weakly convex; prothoracic horn absent; punctures large and dense, wrinkles absent. Scutellum: Punctures small on base, absent on apex. Pygidium: Convex , straight near apex; hirsute on sides, short bristles on middle; punctures coalescent and dense, merging with wrinkles laterally, punctures annular medially.

Measurements of females. Body length: 19.1–28.9 mm. Elytral length: 12.5–18.4 mm. Elytral width: 7.0– 10.6 mm. Head length: 2.5–4.1 mm. Pronotal width: 9.4–13.5 mm. Protibial length: 5.1–7.7 mm.

Geographic distribution. Brazil: Goiás, southern Minas Gerais, Mato Grosso do Sul, Paraná, and Distrito Federal ( Fig. 11 ).

Material examined. Holotype male (MNHN) labeled: a) “Bias”; b) “Ex-Musaeo / JAMES THOMSON”; c) “Bolbocerida / Brés int Thoms / Type”; d) MUSÉUM PARIS / 1952 / COLL R. OBERTHUR”; e) “ Lectotypus / Agaocephala bolbocerida / Thomson”; f) “ LECTOTYPE ”; g) “MNHN / EC2464”. Other specimens: 100 males and 50 females ( CERPE, EPGC) labeled: “ BRASIL, DF, Brasília , / 1100 m, 23.xii.1988, / Luz, ‘ Mortos em palha de / Arroz’, P. & E. Grossi Legs.”; 1 male, 1 female ( EPGC): “ BRASIL, Distrito / Federal, Planaltina, / Núcleo Rural Taquara, / Chácara 70, 10.vii.2005, / ‘coleta manual em raiz de hortaliças’, / C. M. Oliveira col.”; 1 male, 1 female ( EPGC): “ BRASIL, DF, Brasília / Asa Norte, x.2015 / Embrapa CENARGEN, M.O. Breda ”; 1 male ( EPGC): “ BRASIL, Distrito Federal, / Planaltina, Embrapa Cerrados , / 19.xi.2012, ‘coleta manual’, / C. M. Oliveira ”; 4 males, 1 female ( EPGC): “ BRASIL, Goiás, / Formosa, / 01.xi.1996, J. Ampessar leg.”; 1 male ( CERPE): “ BRASIL, Paraná, / Ponta Grossa, / Lageado, xii.1942 ”; 1 male ( CERPE): “ BRASIL, Mato Grosso do Sul, / Dourados, xi.2000, / L. R. Moraes leg.”; 1 male ( EPGC): “ BRASIL, Minas Gerais, / Lavras, UFLA, / 01.xi.1992, Silvio Gusmão leg.”; 2 males ( UFRN): “ BRASIL, Distrito Federal, / Guará ”.

Remarks. The redescription of A. bolboceridus is based on specimens collected by P.C.G. and his father, Everardo J. Grossi, in Brasília and additional material from other states in Brazil, after comparison with the lectotype. The lectotype is a very small specimen with the genitalia missing ( Dechambre & Grossi 1990). However, the other external traits of the lectotype are shared with small-horned males from Brasília municipality, including body color, pronotal punctation, and ocular canthi shape. Within the species group, A. bolboceridus has the broadest geographic distribution in the Cerrado, despite not occurring in localities where A. diceratops and A. vazdemelloi were found. For comparisons among these species, see the Remarks section of both new species.

Figures

FIGURE 1. Habitus of Aegopsis bolboceridus. A, Major male in dorsal view; B, minor male in dorsal view; C, female in dorsal view. Scale bars: 3 mm.

FIGURE 2. A, Head of Aegopsis bolboceridus male, in dorsal view; B, pronotum of Aegopsis bolboceridus male, in dorsal view; C, head of Aegopsis diceratops male, in dorsal view; D, pronotum of Aegopsis diceratops male, in dorsal view; E, head of Aegopsis vazdemelloi male, in dorsal view; F, pronotum of Aegopsis vazdemelloi male, in dorsal view. Black arrow indicating emarginate apex of clypeus in A, E; white arrow indicating micropunctures on pronotum in F. Scale bars: A, C, F, 2 mm; B, D, E, 3 mm.

FIGURE 3. A, Canthus of Aegopsis bolboceridus male, in dorsal view; B, canthus of Aegopsis bolboceridus female, in dorsal view; C, canthus of Aegopsis diceratops male, in dorsal view; D, canthus of Aegopsis diceratops female, in dorsal view; E, canthus of Aegopsis vazdemelloi male, in dorsal view; F, canthus of Aegopsis vazdemelloi female, in dorsal view. White arrow indicating apex inconspicuous of canthi carina in A; black arrows indicating canthi carina split in C; black arrow indicating apex conspicuous of canthi carina in E; black arrows indicating external edge of canthi in B, D, F. Scale bars: 0.5 mm.

FIGURE 4. A, Labrum of Aegopsis bolboceridus male, in dorsal view; B, maxillary palpomere IV of Aegopsis bolboceridus male, in dorsal view; C, maxillary palpomere IV of Aegopsis bolboceridus female, in dorsal view; D, labrum of Aegopsis diceratops male, in dorsal view; E, maxillary palpomere IV of Aegopsis diceratops male, in dorsal view; F, maxillary palpomere IV of Aegopsis diceratops female, in dorsal view; G, labrum of Aegopsis vazdemelloi male, in dorsal view; H, maxillary palpomere IV of Aegopsis vazdemelloi male, in dorsal view; I, maxillary palpomere IV of Aegopsis vazdemelloi female, in dorsal view. Arrows indicating the middle of the labrum in A, G; arrows indicating sensorial area in C, I. Scale bars: 0.5 mm.

FIGURE 5. A, Mandible of Aegopsis bolboceridus male, in ventral view; B, mandible of Aegopsis diceratops male, in ventral view; C, mandible of Aegopsis vazdemelloi male, in ventral view; D, mentum of Aegopsis bolboceridus male, in ventral view; E, mentum of Aegopsis diceratops male, in ventral view; F, mentum of Aegopsis vazdemelloi male, in ventral view. Arrows indicating respectively apical protuberance and protuberance on internal lobe in A; Arrows indicating the internal lobe in B, C; arrow indicating the mentum carina in E. Scale bars: 0.5 mm.

FIGURE 6. A, Aedeagus of Aegopsis bolboceridus, in lateral view; B, parameres of Aegopsis bolboceridus, in ventral view; C, parameres of Aegopsis bolboceridus, in dorsal view; D, aedeagus of Aegopsis diceratops in lateral view; E, parameres of Aegopsis diceratops in ventral view; F, parameres of Aegopsis diceratops in dorsal view; G, aedeagus of Aegopsis vazdemelloi in lateral view; H, parameres of Aegopsis vazdemelloi in ventral view; I, parameres of Aegopsis vazdemelloi in dorsal view. White arrows in the left indicating ventral carina of parameres in B, E, H; white arrows upward indicating inferior edge of parameres in B, E, H. Scale bars: A, D, G, 1 mm; B, C, E, F, H, I, 0.5 mm.

FIGURE 7. A, Head of Aegopsis bolboceridus female in dorsal view; B, head of Aegopsis bolboceridus female in lateral view; C, head of Aegopsis diceratops female in dorsal view; D, head of Aegopsis diceratops female in lateral view; E, head of Aegopsis vazdemelloi female in dorsal view; F, head of Aegopsis vazdemelloi female in lateral view. Black arrow indicating head punctures in A; black arrow indicating clypeus trapezoidal in C; white arrow indicating vertex in C; black arrow indicating frontal tubercles in D; white arrow indicating head punctures in E. Scale bars: 1 mm.

FIGURE 8. A, Mandible of Aegopsis bolboceridus female in ventral view; B, mandible of Aegopsis diceratops female in ventral view; C, mandible of Aegopsis vazdemelloi female in ventral view; D, mentum of Aegopsis bolboceridus female in ventral view; E, mentum of Aegopsis diceratops female in ventral view; F, mentum of Aegopsis vazdemelloi female in ventral view. Arrows indicating respectively apical protuberance and protuberance on internal lobe in A; arrow indicating middle part of mesal brushes in B; arrow indicating internal lobe in C. Scale bars: 0.5 mm.

FIGURE 11. Distribution map of the species in the Aegopsis bolboceridus species group.