Phanaeus moroni Arnaud, 2001

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 : 453

Phanaeus moroni Arnaud, 2001 stat. rev.

( Figs 6–7 , 33 , 44 )

Phanaeus tridens moroni Arnaud, 2001: 7 . Type locality: Mexico, Veracruz, Catemaco, Dos Amates.

Type material examined. MEXICO: V ERACRUZ: HOLOTYPE (originally designated by ARNAUD 2001, examined from photographs; Fig.7 ):♂ Dos Amates, Catemaco ( PFASF).

Non-type material examined. MEXICO: V ERACRUZ: 2 ♂♂, Dos Amates, Catemaco ( GHVM, VMPM); 1 ♂ ( CMNC).

Diagnosis. Sides of pronotal disc metallic green-yellow, becoming bright red to wine-garnet red towards medial portion of pronotum; postero-medial portion of pronotal disc almost completely black ( Figs 6–7 , 44 ). Sides of pronotal disc finely granulate and becoming granulorugose on outer margin of disc ( Figs 6–7 , 44 ). Pronotal disc weakly but coarsely rugose ( Figs 6–7 ). Posteromedial process of pronotum produced into denticle, strongly widened laterally (almost reaching anteromedial carina), elongate and apically bifurcated ( Figs 33 , 44 ). Anteromedial portion of pronotal disc with two denticles, usually joined by strongly developed, medial carina ( Fig. 44 ). Anterolateral margins of disc with strongly developed ridge of tubercles ( Fig. 44 ). Posterolateral angles shorter than posteromedial process of pronotum ( Fig. 33 ). Tri-coloured elytra, metallic green-red-yellow ( Figs 6–7 ). Elytral striae scabriculous, distinctly impressed, superficially punctate ( Figs 6–7 ). Elytral interstriae scabriculous, smooth, superficially punctate, convex ( Figs 6–7 ).

Variability. Minor male. Similar to major males, except for reduction of secondary sexual characters (i.e., cephalic horn, pronotal process and posterolateral angles). Female. Similar to male, except for head showing trituberculate carina; pronotal sculpture granulate; and anteromedial carina of pronotum followed by posterior concavity. Apparently, this species is not variable in colour ( Figs 6–7 , 44 ).

Comments. Phanaeus moroni was originally considered a subspecies of P. tridens due to the Veracruz populations being distinct from the rest of the species in colour ( Figs 6–7 , 44 ) and in the shape of the posteromedian process of the pronotum ( Figs 33 , 44 ). Subsequently, EDMONDS & ZÍDEK (2012) regarded P. moroni as a “colour variant” and a junior subjective synonym of P. tridens ( Figs 1–5 , 32 , 43 ). The unique combination of characters of P. moroni demonstrates that it deserves a full species status. The posteromedial process of pronotum in major males of P. moroni is distinctly narrowed medially in posterior view ( Fig. 33 ; not narrowed in P. tridens Fig. 32 ), while the ridge of tubercles of anterolateral margins of pronotal disc are more raised in P. moroni ( Fig. 44 ) than in P. tridens ( Fig. 43 ). Along its distribution, Phanaeus tridens indeed has a bright green-red chromatic phase ( Fig. 2 ). This fact likely led EDMONDS & ZÍDEK (2012) to consider P. tridens and P. moroni synonyms. Nevertheless, the bright green-red chromatic phase of P. tridens ( Fig. 2 ) never shows the wine-garnet red to black pronotal disc and the widened posteromedial process of pronotum of P. moroni ( Figs 6–7 , 44 ).

Distribution. Mexico: Los Tuxtlas region, Veracruz ( Fig. 64 ).

Figures

Figs 6–7. Phanaeus moroni Arnaud, 2001, stat. rev. 6 – male; 7 – holotype and labels (by Patrick Arnaud, PFASF). 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 1–5. Phanaeus tridens Castelnau, 1840. 1 – male green phase; 2 – male green-red phase; 3 – neotype and labels, present designation (by Christophe Rivier, MNHN); 4 – P. frankenbergeri junior subjective synonymy, holotype and labels (by Jiří Hájek, NMPC); 5 – Eൽආඈඇൽඌ’ (1994) neotype of P. tridens and labels (by Simon Hinkley, NMVA). Scale bar = 1.0 mm.

Fig. 64. Predicted distribution of P. tridens Castelnau, 1840, P. moroni Arnaud, 2001 and P. balthasari Arnaud, 2001. The distribution of P. coeruleus Bates, 1887 was not modelled because it is only known from a single locality that needs confirmation.