Orizabus Species

Ratcliffe, Brett C. & Cave, Ronald D., 2010, New species of Orizabus Fairmaire (Coleoptera: Scarabaeidae: Dynastinae: Pentodontini) from Mexico and Guatemala, with a revised key and checklist of the species in the genus, Insecta Mundi 2010 (127), pp. 1-16 : 12-14

Key to Females of Adult Orizabus Species

(modified from Delgado 2008)

(The females of O. delgadoi , O. epithecus , and O. mezclus remain unknown)

1. Elytra weakly striate, at most with feebly impressed rows of punctures ................................... 2

— Elytra furrowed, with distinctly impressed, punctate striae ...................................................... 3

2(1). Pronotum with basal bead. Apical tooth of protibia narrowly rounded. Length 24-27 mm. Southern Mexico .............................................................. O. dechambrei Morón, Tapia and Aragón

— Pronotum without basal bead. Apical tooth of protibia broadly rounded. Honduras..................... ................................................................................................... O. botox Ratcliffe and Cave

3(1). Protibia entire, lacking lobes or teeth ......................................................................................... 4

— Protibia with lobes or teeth on external margin ......................................................................... 6

4(3). Subapical carina of clypeus straight or nearly so. Length 22-25 mm. Southeastern Mexico, Guatemala, Nicaragua......................................................................... O. tuberculatus Prell

— Subapical carina of clypeus bilobed ............................................................................................. 5

5(4). Pronotum without tubercle. Metatibia at apex with less than 30 spinules. Length 21-26 mm. Central and northwestern Mexico............................................................ O. rubricollis Prell — Pronotum with strong tumescence on anterior margin. Metatibia at apex with more than 40 spinules. Length 23-30 mm. El Salvador and Honduras............................................................ .............................................................................. O. teamscaraborum Ratcliffe and Cave

6(3). Antenna 9-segmented. Length 15-18 mm. Central Mexico ............................................................ ........................................................................... O. vulcanicus Morón, Tapia and Aragón

— Antenna 10-segmented ................................................................................................................. 7

7(6). Pygidium with deep, preapical depression. Length 16-17 mm. Eastern Mexico ........................... ........................................................................................................... O. endrodianus Morón

— Pygidium without preapical depression ....................................................................................... 8

8(7). Frontoclypeal region with weak line but lacking tubercle or carina .......................................... 9

— Frontoclypeal region with tubercle (may be small) and/or carina (may be weak) .................... 10

9(8). Metatibia at apex with about 24 spinules. Honduras..... O. hondurensis Ratcliffe and Cave

— Metatibia at apex with about 30-34 spinules. Honduras....... O. puchicus Ratcliffe and Cave

10(8). Pygidium completely, densely punctate to rugopunctate. Length 14-19 mm. United States, eastern Mexico.............................................................................................. O. pyriformis (LeConte)

— Pygidium rugopunctate only at base and basal angles, elsewhere variably sparsely to moderately punctate; O. fairmairei may occasionally be densely punctate ............................................. 11

11(10). Posterolateral area of pronotal disc nearly smooth ................................................................... 12

— Posterolateral area of pronotal disc with at least some punctures ........................................... 13

12(11). Pygidium with at least some small punctures on disc. Length 16-19 mm. Central, western, northwestern, and southern Mexico................................................................. O. batesi Prell

— Pygidium without punctures on disc. Length 18-20 mm. Southern Mexico ................................. ......................................................................................................... O. rawlinsi Dechambre

13(11). Subapical carina of clypeus straight ......................................................................................... 14

— Subapical carina of clypeus emarginate or bilobed ................................................................... 15

14(13). Frontoclypeal region with distinct, transverse carina. Length 15-21 mm. Central, western and northwestern Mexico.................................................................... O. isodonoides Fairmaire

— Frontoclypeal region with weak carina and small tubercle. Length 13-16 mm. Northwestern Mexico .................................................................................................... O. ratcliffei Delgado

15(13). Size small, length usually less than 20 mm ............................................................................. 16

— Size larger, length usually more than 20 mm .......................................................................... 19

16(15). Pygidium with dense, small punctures except at center apex. Length 16-19 mm. Veracruz, Mexico.............................................................................................. O. thomasi Ratcliffe and Cave

— Pygidium not densely punctate, instead with sparse, minute to small punctures .................. 17

17(16). Pygidium with sparse, small punctures. Best identified by collecting in association with males. Length 16-19 mm. Sonora, Mexico............................ O. amalgamatus Ratcliffe and Cave

— Pygidium with sparse, minute punctures ................................................................................. 18

18(17). Body shape subparallel, lateral margins becoming slightly wider posteriorly. Pronotum at midline “short”, length:width ratio 3:5. Best identified by collecting in association with males. Length 15-19 mm. Central, western and southern Mexico..................................................................... .............................................................................. O. cuernavacensis Delgado and Deloya — Body shape rotund, lateral margins becoming much wider posteriorly. Pronotum at midline “long”, length:width ratio 4:5. Best identified by collecting in association with males. Length 14-19 mm. Southern and eastern Mexico...................................................... O. fairmairei (Bates)

19(15). Metatibia at apex with more than 30 spinules. Upper genital plates with basal projections and short setae. Length 23-27 mm. Central, eastern, western and northwestern Mexico............... .................................................................................................................. O. brevicollis Prell

— Metatibia at apex with less than 30 spinules. Upper genital plates without basal projections and with long setae ........................................................................................................................ 20

20 (19). Clypeus with apex not extending beyond clypeal carina, carina with 2 contiguous teeth. Length 20-27 mm. United States, northern Mexico.............................................. O. ligyroides Horn

— Clypeus with apex extending beyond broadly bilobed supapical carina .................................... 21

21(20). Protibial spur extending to about apex of first tarsomere, rarely longer. Length 20-27 mm. United States, Mexico, Guatemala, El Salvador, Honduras........................... O. clunalis (LeConte)

— Protibial spur extending to apex of second tarsomere, rarely shorter. Length 23-27 mm. Oaxaca, Mexico................................................................................................... O. subaziro Ratcliffe