Orizabus dechambrei Morón, Tapia and Aragón, 2003

Morón, Miguel Angel, Tapia, Ana María & Aragón, Agustín, 2003, Two new species of the genus Orizabus Fairmaire (Coleoptera: Scarabaeidae: Dynastinae) from southern and central Mexico, Zootaxa 176, pp. 1-8 : 4-8

Orizabus dechambrei Morón, Tapia and Aragón , sp. nov. ( Figs. 11­22 )

Diagnosis. This species is distinguished from other Orizabus species by the following combination of characters: head with transverse clypeal carina sinuate, a small or weak tubercle on fronto­clypeal suture, antennae with 10 segments, pronotum with large anterior tubercle and wide depression, elytra weakly striate, male foretibia without teeth; female foretibia tridentate, female pygidium widely convex and without keel or depressions.

Description. Holotype. Male: Length 26.8 mm; width across humeri 13.9 mm. Color shiny dark brown dorsally and ventrally, nearly black on pronotum and slightly reddish on elytra. Head: clypeus with surface transversely rugo­punctate, apex broadly rounded, transverse clypeal carina prominent, sinuate. Frons moderately convex, densely rugopunctate, with small, weak, rounded tubercle on anterior margin at middle of carinate frontoclypeal suture. Interocular width equals 4.8 transverse eye diameters ( Figs. 11­12, 18 ). Antenna with 10 segments, club 1.4 times longer than stem. Pronotum: surface shiny, anterior half of disc densely punctate and aciculate, punctures deep and round, with anterior angles rugopunctate; posterior half of disc only aciculate near weakly furrowed midline, punctation progressively dense toward sides. Anterior margin with large, horn­like tubercle and wide, deep depression behind tubercle ( Fig. 12 ). Posterior margin with weak marginal line, line not interrupted at middle. Elytra: surface aciculate, with 3 weakly impressed striae between suture and lateral edge of humeral umbone, plus 1 oblique stria near inner side of humeral umbone, sides without striae. Intervals inpunctate. Pygidium : surface strongly convex in lateral view, finely rugopunctate at basal angles; disc sparsely punctate, weakly aciculate, nearly smooth, with deep transverse pit before apex. Ve n te r: prosternal process large, apex rounded, densely clothed with long, ferruginous setae. Legs: foretibia without teeth, blade­like ( Fig. 14 ). Hindtibia with 2 distinct, submedial, transverse carinae ( Fig. 16 ). Parameres ( Figs. 20­21 ): Apical portion of each paramere abruptly expanded, without lateral tooth or accesory blades.

Allotype. Length 27.1 mm; width across humeri 13.5 mm. As holotype except as follow: Head: fronto­clypeal suture and frontal tubercle slightly larger. Pronotum: widely convex, without anterior tubercle and depression ( Fig. 17 ); anterior half of disc densely punctate; posterior half of disc aciculate at middle, with deep punctures near latero­basal borders. Pygidium : surface slightly convex, without preapical transverse pit. Legs: foretibia nearly tridentate ( Fig. 15 ). Genital plates ( Fig. 22 ): basal plates subquadrate, without setae. Distal plates widely convex, with apical border widely curved, with many setae.

Variation (1 paratype). Length 24.2 mm. Humeral width 13.1 mm. Male: Head: clypeus with transverse clypeal carina prominent, deeply sinuate ( Fig. 19 ). Pronotum: anterior margin with tubercle and fovea smaller ( Fig. 13 ). Elytra: with 8 weak impressed rows of small, round punctures between suture and lateral edge of humeral umbone, plus 1 short row at base of second interval, sides with 4 irregular rows; 1 oblique stria near inner side of humeral umbone; intervals shiny, aciculate. Pygidium less convex.

Material examined (3 specimens). Holotype male: MEXICO. Guerrero: Rancho Omiltemi, 5 June 1985, Col. A. Luis ( MXAL / IEXA). Allotype female: Guerrero, Tlacotepec, 6 km W Puerto del Gallo, El Iris, 2200 m, 4 August 1983, Col. A. Luis ( MXAL / IEXA). Paratype male; Guerrero: Omiltemi, 5 July 1985, Col. I. Vargas ( MXAL / IEXA).

Habitat. The specimens were collected on the soil in pine­oak or oak forests at 2200­ 2300 m elevation.

Geographical distribution ( Fig. 10 ). This species is known only from Parque Ecológico Estatal Omiltemil and the surrounding areas near Chilpancingo, Guerrero, Mexico.

Taxonomic relationships. Orizabus dechambrei is in the group of species whose males have a pronotal tubercle and pronotal depression and have the foretibia lacking teeth. This group also includes O. tuberculatus Prell and O. clunalis LeConte. The males of O. dechambrei are easily separated from the other species in this group by the weak frontal tubercle, pronotum with wide and deep depression behind the anterior large, hornlike tubercle, elytra weakly striate or nearly smooth, and the apex of the parameres abruptly expanded, without lateral tubercles.

Etymology. This species is named after Roger­Paul Dechambre in recognition of his extensive work done on the Dynastinae of the world.

Key to species of Orizabus Fairmaire (Modified from Delgado­Castillo & Deloya, 1990)

1­ Pronotum with tubercle and depression on anterior half ............................................................ 2

­ Pronotum without tubercle or depression on anterior half.......................................................... 6

2­ Frons with tubercle in middle of anterior border. External margin of foretibia without teeth or tridentate. Body length 21­27 mm .............................................................................................. 3

­ Frons with straight transverse carina. External margin of foretibia bisinuate. Body length 14­19

mm. Mexico................................................................................ O. isodonoides Fairmaire, male 3. External margin of foretibia without teeth, without emarginations. Frontal tubercle weak, short, rounded ....................................................................................................................................... 4

­ External border of foretibia tridentate. Frontal tubercle large, erect, with rounded apex. Mexico............................................................................................................ O. subaziro Ratcliffe, male

4­ Clypeal carina straight. Apical third of parameres with 2 lateral tubercles. Mexico, Guatemala and Nicaragua.................................................................................... O. tuberculatus Prell, male

­ Clypeal carina sinuate, forming 2 rounded teeth. Apical third of parameres without tubercles. 5

5­ Pronotum with narrow, deep depression behind small, anterior tubercle. Elytra deeply punctate­striate. Body length 21­26 mm. U.S.A. and Mexico................... O. clunalis LeConte, male

­ Pronotum with wide, shallow depression behind large, anterior horn­like tubercle. Elytra weakly striate or nearly smooth. Body length 24­27 mm. Southern Mexico............................... ........................................................................................................ O. dechambrei sp. nov. male

6­ Frons with transverse carina. External margin of foretibia tridentate. Body length 14­19 mm. Northwestern and central Mexico............................................ O. isodonoides Fairmaire, female

­ Frons with tubercle on middle of anterior border. External margin of foretibia without teeth, bisinuate, or tridentate. Body length 14­28 mm ......................................................................... 7

7­ Antenna 9­segmented. Body length 15­18 mm. Central Mexico................................................. ........................................................................................ O. vulcanicus sp. nov. male and female

­ Antenna 10­segmented. Body length 14­28 mm ....................................................................... 8

8­ External margin of foretibia without teeth .................................................................................. 9

­ External margin of foretibia bisinuate or tridentate .................................................................. 11

9­ Transverse clypeal carina straight. Mexico, Guatemala and Nicaragua....................................... ........................................................................................................ O. tuberculatus Prell , female

­ Transverse clypeal carina sinuate, bidentate ............................................................................ 10

10­ Elytra with second interval smooth. Parameres with lateral carina on apical third, the apex notched and glabrous. Body length 20­24 mm. Mexico.... O. rubricollis Prell, male and female

­ Elytra with second interval with scattered punctures near apical callus. Parameres without lateral carina on apical third, the apex entire and with long setae. Body length 15­19 mm. Southern Mexico............................................ O. cuernavacensis Delgado­Castillo and Deloya , male

11­ Posterolateral area of pronotal disc sparsely punctate ............................................................. 12

­ Posterolateral area of pronotal disc densely punctate ............................................................... 13

12­ Apex of inner spur of hind tibia curved. Parameres short and widely bifurcate. Pygidium of female with deep preapical pit. Body length 16­18 mm. Hidalgo, Mexico.................................. ...................................................................................... O. endrodianus Morón, male and female

­ Apex of inner spur of hind tibia straight. Parameres long and narrowed, weakly notched at apex. Pygidium of female without preapical pit. Body length 16­19 mm. Western and southeastern Mexico........................................................................... O. batesi Prell, male and female

13­ Pygidium densely, entirely rugopunctate. Body length 14­16 mm. U.S. A and northern Mexico. ...................................................................................... O. pyriformis LeConte, male and female

­ Pygidium rugopunctate on base and sides ................................................................................ 14

14­ Elytra weakly striate or nearly smooth. Body length 24­27 mm. Southern Mexico..................... ...................................................................................................... O. dechambrei sp. nov. female

­ Elytral deeply punctate striate. Body length 15­28 mm ............................................................ 15

15­ Apex of metatibia with 15­18 spine­like setae. Pygidium without punctures on center of disc .................................................................................................................................................. 16

­ Apex of metatibia with 20­28 spine­like setae. Pygidium with minute or shallow punctures on

center of disc ............................................................................................................................. 17 16­ Body length 18­21 mm. Parameres with triangular, strong tooth near middle of lateral border. Oaxaca, Mexico......................................................... O. rawlinsi Dechambre, male and female

­ Body length 15­19 mm. Morelos, State of Mexico, Guerrero, and Jalisco, Mexico.................... ............................................................. O. cuernavacensis Delgado­Castillo and Deloya, female

17­ Anterior margin of pronotum with middle of marginal bead broader than dorsal area of clypeal apex. Oaxaca and Guerrero, Mexico............................................... O. subaziro Ratcliffe, female

­ Anterior margin of pronotum with middle of marginal bead as broad or narrower as dorsal area of clypeal apex .......................................................................................................................... 18

18­ Central and basal area of pronotal disc with numerous deep, round punctures. Distal half of parameres narrowed, with preapical, rounded projection on lateral border. Body length 17­18 mm. Eastern and southeastern Mexico.................. O. fairmairei Bates, male (female unknown)

­ Central and basal area of pronotal disc with scattered, minute punctures or lacking punctures. Parameres without preapical, rounded projection on lateral border. Body length 20­28 mm. Southern U.S.A. and Mexico.................................................................................................... 18

19­ Body length 20­23 mm. Parameres narrowed, curved outward, with a small tooth­like projection at middle of lateral border, slightly expanded and bifid at apex. Upper genital plates of female with basal projections and short setae .................... O. brevicollis Prell, male and female

­ Body length 22­28 mm. Upper genital plates of female without basal projections and long setae ......................................................................................................... O. clunalis LeConte , female.

Figures

FIGURE 10. Distribution of Orizabus vulcanicus (q) and Orizabus dechambrei (x).

FIGURES 11 ­ 22. Orizabus dechambrei Morón, Tapia and Aragón, sp. nov. 11 ­ Male head, dorsal view; 12 ­ Holotype head and pronotum, lateral view; 13 ­ Paratype ibid; 14 ­ Male foretibia, dorsal view; 15 ­ Female foretibia, dorsal view; 16 ­ Male hindtibia, lateral view; 17 ­ Allotype head and pronotum, lateral view; 18 ­ Holotype clypeal carina, frontal view; 19 ­ Paratype clypeal carina; 20 ­ Parameres, distal view; 21 ­ Male genital capsule, lateral view; 22 ­ Female genital plates, ventral view. Scale bar 1 mm.