Phanaeus substriolatus Balthasar, 1939

Moctezuma, Victor, Halffter, Gonzalo & Lizardo, Viridiana, 2021, The Phanaeus tridens species group (Coleoptera: Scarabaeoidea): a dung beetle group with genital morphological stasis but a changing ecological niche, Acta Entomologica Musei Nationalis Pragae 61 (2), pp. 447-482 : 459

Phanaeus substriolatus Balthasar, 1939 , stat. rev.

( Figs 14–15 , 36 , 48 , 58 )

Phanaeus substriolatus Balthasar, 1939: 245 . Type locality: Mexico.

Type material examined. MEXICO: HOLOTYPE (originally designated by BALTHASAR 1939, examined from photographs; Fig. 15 ): ♂, without specific locality ( NMPC: Mus. Nat. Pragae Inv. 26349).

Non-type material studied. MEXICO: G UERRERO: 1 ♂ (examined from photographs), Amula ( BMNH: 013667803). OAXACA: 1 ♂ 1 ♀, Cerro Colorado, San Juan Bautista Cuicatlán ( VMPM). P UEBLA: 1 ♂ 1 ♀, San Mateo Zoyamazalco, Coyotepec ( VMPM); 1 ♀, Izucar de Matamoros (examined from photographs, BMNH: NHMUK 013667799). U NKNOWN LOCAL I TY: 1 ♂ (examined from photographs, BMNH: NHMUK 013667796).

Diagnosis. Metallic dark blue to black ( Figs 14–15 , 48 , 58 ). Sides of pronotal disc finely granulate, becoming granulorugose on raised outer margin of disc; pronotal disc weakly but coarsely rugose, more sparsely posteriorly ( Figs 14–15 , 48 ). Posteromedial process of pronotum produced into a slender, conical or triangular and elongate denticle ( Figs 36 , 48 ). Anteromedial portion of pronotal disc with two denticles and variable in number of tubercles ( Fig. 48 ). Anterolateral margins of pronotal disc without ridge or line of tubercles ( Figs 48 ). Posterolateral angles of pronotum shorter than posteromedial process and produced into two conical or triangular elongate denticles ( Figs 36 , 48 ). Elytral striae smooth, scabriculous, superficially impressed or partially erased, superficially punctate ( Figs 14–15 ). Elytral interstriae scabriculous, smooth, superficially punctate, flat; I, III, V and VI frequently with lightly roughened integument ( Figs 14–15 ).

Variability. Minor male. Similar to major males, except for the reduction of the secondary sexual characters (i.e., cephalic horn, pronotal processes and posterolateral angles). Particularly, the posterolateral angles and posteromedial process of pronotum are reduced into tree pronotal keels or conical tubercles ( Fig. 15 ). Female. Similar to the male, except for the head showing a trituberculate carina; pronotal sculpture granulate to punctate posteriorly; pronotum with anteromedial black macula, and anteromedial carina followed by a posterior concavity ( Fig. 58 ).

Comments. ARNAUD (1982b: 125) established the synonymy between P. substriolatus ( Figs 14–15 , 36 , 48 , 58 ) and P. daphnis ( Figs 11–13 , 35 , 46 , 57 ), which was followed by subsequent authors ( EDMONDS 1994, ARNAUD 2002, EDMONDS & ZÍDEK 2012). After examining the holotype ( Fig. 15 ) and additional material ( Figs 14 , 36 , 48 , 58 ), we suggest that P. substriolatus deserves full species status because it has a unique combination of characters: the dark blue to black colouration is unique of this species ( Figs 14–15 , 48 , 58 ; dark blue with turquoise sheen in P. coeruleus , Figs 13 , 47 ; green or green-blue in P. daphnis , Figs 11–13 , 46 , 57 ; green or green-red in P. herbeus , Figs 16–17 , 49 , 59 ), the posteromedial process of pronotum produced into an elongate denticle in P. substriolatus ( Figs 36 , 48 ) separates it from P. daphnis ( Figs 35 , 46 ), while the elytral interstriae I, III and V with lightly roughened integument distinguishes P. substriolatus ( Figs 14–15 ) from P. coeruleus (smooth elytral interstriae I–V, Fig. 13 ). Finally, the elytral striae superficially impressed or partially erased are unique of P. substriolatus ( Figs 14–15 ).

Distribution. Mexico: southern Puebla to northern Oaxaca ( Fig. 65 ). The record from central Guerrero needs confirmation.

Figures

Figs 14–15. Phanaeus substriolatus Balthasar, 1939, stat. rev. 14 – male; 15 – holotype and labels (by Jiří Hájek, NMPC). Scale bar = 1.0 mm.

Figs 32–42. Posterior view of pronotum of major male. 32 – P. tridens Castelnau, 1840; 33 – P. moroni Arnaud, 2001, stat. rev.; 34 – P. bal- thasari Arnaud, 2001, stat. rev.; 35 – P. daphnis Harold, 1863; 36 – P. substriolatus Balthasar, 1939, stat. rev.; 37 – P.herbeus Bates, 1887, stat. rev.; 38 – P.furiosus Bates, 1887; 39 – P.pseudofurcosus Balthasar, 1939, stat. rev.; 40 – P. nimrod Harold, 1863; 41 – P. victoriae Moctezuma sp. nov.; 42 – P. eximius Bates, 1887. Scale bar = 1.0 mm.

Figs 43–54. Lateral view of pronotum of major male. 43 – P. tridens Castelnau, 1840; 44 – P. moroni Arnaud, 2001, stat. rev.; 45 – P. balthasari Arnaud, 2001; 46 – P. daphnis Harold, 1863; 47 – P. coeruleus Bates, 1887, stat. rev. (holotype, by Keita Matsumoto, BMNH); 48 – P. substriolatus Balthasar, 1939, stat. rev.; 49 – P. herbeus Bates, 1887, stat. rev. (green-red phase); 50 – P. furiosus Bates, 1887 (green phase); 51 – P. pseudofurcosus Balthasar, 1939, stat. rev.; 52 – P. nimrod Harold, 1863; 53 – P. victoriae Moctezuma sp. nov. (holotype); 54 – P. eximius Bates, 1887. Scale bar = 1.0 mm.

Figs 55–62. Pronotum of female. 55 – P. tridens Castelnau, 1840; 56 – P. balthasari Arnaud, 2001, stat. rev.; 57 – P. daphnis Harold, 1863; 58 – P. substriolatus Balthasar, 1939, stat. rev. (dark blue-black phase); 59 – P.herbeus Bates, 1887, stat. rev. (green phase); 60 – P. nimrod Harold, 1863 (blue-green phase); 61 – P. furiosus Bates, 1887 (dark blue phase); 62 – P. pseudofurcosus Balthasar, 1939, stat. rev. Scale bar = 1.0 mm.

Figs 10–12. Phanaeus daphnis Harold, 1863. 10 – male green phase; 11 – male deep blue-green phase; 12 – lectotype and labels (by Christophe Rivier, MNHN). Scale bar = 1.0 mm.

Fig. 13. Phanaeus coeruleus Bates, 1887, stat. rev., holotype and labels (by Keita Matsumoto, BMNH).

Figs 16–18. Phanaeus herbeus Bates, 1887, stat. rev. 16 – male green phase; 17 – holotype and labels (by Mario Cupello, UFPR); 18 – P. tricornis Olsoufieff, 1924, junior subjective synonymy, redrawn from Oඅඌඈඎൿංൾൿൿ (1924). Scale bar = 1.0 mm.

Fig. 65. Predicted distribution of P. daphnis Harold, 1863, P. substriolatus Balthasar, 1939 and P. herbeus Bates, 1887.