Phanaeus herbeus Bates, 1887

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 : 459-461

Phanaeus herbeus Bates, 1887 stat. rev.

( Figs 16–18 , 37 , 49 , 59 )

Phanaeus daphnis var. herbeus Bates, 1887: 61 . Type locality: Mexico.

Phanaeus tricornis Olsoufieff, 1924: 105 . Type locality: Without specific locality. Synonymy established by ARNAUD (1982a: 116) and confirmed here.

Type material examined. MEXICO: HOLOTYPE of P. herbeus (fixed by monotypy by BATES 1887, examined from photographs; Fig. 17 ): ♂, without specific locality ( BMNH: NHMUK 013667783).

Non-type material examined. MEXICO: E STADO DE M ÉX I CO: 1♀, Ixtapan del Oro ( IEXA); 8♂♂ 1♀, Santo Tomás de los Plátanos ( GHVM: 6 ♂♂ 1 ♀; VMPM: 2 ♂♂); 5 ♂♂ 2 ♀♀, Temascaltepec ( GHVM: 4 ♂♂ 1 ♀; VMPM: 1 ♂ 1 ♀); 1 ♀, Tenancingo ( GHVM), 1 ♀, Valle de Bravo ( VMPM); 2♂♂ 5♀♀, Zacazonapan ( IEXA). M I CHOACÁN: 1♀, Tuxpan ( VMPM). M ORELOS: 2 ♂♂, Tepoztlán ( GHVM). W I THOUT SPEC I F I C LOCAL I TY: 3 ♂♂ ( GHVM: 2 ♂♂; VMPM: 1 ♂).

Diagnosis. Metallic green ( Figs 16–17 , 59 ), occasionally with a red sheen ( Fig. 49 ). Sides of pronotal disc finely granulate becoming granulorugose on raised outer margin of disc; pronotal disc weakly but coarsely rugose, more sparsely posteriorly ( Figs 16–17 , 49 ). Posteromedial process of pronotum strongly produced into slender, conical or triangular denticle ( Figs 18 , 37 , 49 ). Anteromedial portion of pronotal disc with one triangular, sharply acute tubercle, or with some rounded tubercles ( Fig. 49 ). Anterolateral margins of pronotal disc with distinctly developed ridge of tubercles ( Fig. 49 ). Anterolateral margins of pronotal disc without ridge or line of tubercles ( Fig. 49 ). Posterolateral angles of pronotum slightly less developed than posteromedial process and produced into two conical or triangular elongate denticles ( Figs 18 , 37 , 49 ). Elytral striae scabriculous, distinctly impressed, superficially punctate ( Figs 16–17 ). Elytral interstriae scabriculous, smooth, superficially punctate, convex; III, V and VI frequently with lightly roughened integument ( Figs 16–17 ).

Variability. Minor male. Similar to major males, except for reduction of secondary sexual characters (i.e., cephalic horn, pronotal processes and posterolateral angles). Particularly, posterolateral angles and posteromedial process of pronotum are reduced into three conical tubercles as seen in P. substriolatus ( Fig. 15 ). Female. Similar to male, except for head showing trituberculate carina; pronotal sculpture granulate; pronotum with anteromedial black macula, and anteromedial carina followed by posterior concavity ( Fig. 59 ).

Comments. According to EDMONDS (1994), the holotype was fixed by monotypy ( Fig. 17 ). The type locality provided by the labels ( Mexico) and the morphology of the specimen are consistent with those mentioned in the original description of P. herbeus ( Fig. 17 ). Phanaeus herbeus ( Figs 16–18 , 37 , 49 , 59 ) was originally described as a variety of P. daphnis ( Figs 11–13 , 35 , 46 , 57 ) by BATES (1887). Later, the name was deemed a junior subjective synonym of P. daphnis by EDMONDS (1994) and EDMONDS & ZÍDEK (2012). On the other hand, ARNAUD (2002) considered P. herbeus a valid subspecies of P. daphnis . We believe that P. herbeus merits full species status. The typical green chromatic phases of P. herbeus ( Figs 16–17 , 59 ) and P. daphnis ( Figs 10–12 , 46 , 57 ) are similar. Nevertheless, the red-green chromatic phase is only found in P. herbeus ( Fig. 49 ), whereas P. herbeus never shows a deep blue-green chromatic phase as seen in P. daphnis ( Fig. 11 ). Furthermore, major males of P. herbeus always show the posteromedial process of pronotum strongly produced into a slender denticle ( Figs 18 , 37 , 49 ; small denticle in P. daphnis , Figs 35 , 46 ). The convex interstriae separates P. herbeus ( Figs 16–17 ) and closely related species with flat interstriae ( P. daphnis , Figs 10–12 ; P. coeruleus , Fig. 13 ; P. substriolatus Figs 14–15 ).

Additionally, the minor males of P. herbeus show the posteromedial process and the posterolateral angles of pronotum produced into three small conical tubercles (as in Fig. 15 ; the posteromedial process obsolete and the posterolateral angles carinate in P. daphnis ). Phanaeus herbeus and P. daphnis are partially sympatric ( Fig. 65 ), but the pronotal morphology is consistent and likely hybrid specimens were not found.

Phanaeus substriolatus ( Figs 14–15 , 36 , 48 , 58 ) is also similar to P. herbeus . The latter is distinguished by the elytral interstriae distinctly convex ( Figs 16–17 ; elytral interstriae distinctly flattened in P. substriolatus , Figs 14–15 ) and the presence of green ( Figs 16–17 , 59 ) or green-red ( Fig. 49 ) specimens in its populations (specimens always dark blue in P. substriolatus , Figs 14–15 , 48 , 58 ). Phanaeus herbeus and P. substriolatus are not sympatric ( Fig. 65 ). Phanaeus herbeus was figured by DELOYA & COBARRUBIAS-MELGAR (2014) instead of P. daphnis . ARNAUD (1982a) proposed P. tricornis ( Fig. 18 ) as a junior subjective synonym of P. herbeus . Unfortunately, we were not able to revise the lectotype of P. tricornis , but its original description and illustration are fairly detailed and allowed us to confirm this synonymy.

Distribution. Mexico: Estado de México, Michoacán, Morelos and Puebla ( Fig. 65 ).

Figures

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.

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 14–15. Phanaeus substriolatus Balthasar, 1939, stat. rev. 14 – male; 15 – holotype and labels (by Jiří Hájek, NMPC). 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).

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