Phanaeus coeruleus 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 : 457-459

Phanaeus coeruleus Bates, 1887 , stat. rev.

( Figs 13 , 47 )

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

Type material examined. MEXICO: HOLOTYPE (fixed by monotypy by BATES 1887, examined from photographs; Figs 13 , 47 ): ♂, Puebla ( BMNH: NHMUK 013667754).

Diagnosis. Metallic dark blue with turquoise sheen ( Figs 13 , 47 ). Sides of pronotal disc granulate anteriorly, becoming punctate with effaced granules posteriorly. Pronotal disc coarsely rugose ( Figs 13 , 47 ). Posteromedial process of pronotum produced into short denticle, not bifurcated but truncate apically ( Fig. 47 ). Anterolateral margins of pronotal disc without ridge or line of tubercles ( Fig. 47 ). Posterolateral angles of pronotum much longer than posteromedial process ( Fig. 47 ). Elytral striae scabriculous, distinctly impressed, superficially punctate ( Fig. 13 ). Elytral interstriae scabriculous, distinctly smooth (except for interstriae VI and VII with lightly roughened integument), superficially punctate, flat ( Fig. 13 ).

Variation. Minor male. Unknown. Female. Unknown.

Comments. ARNAUD (1982a: 113) collectively designated lectotypes for some species-group names of Phanaeus housed at BMNH. More specifically, instead of pointing out which individual syntype was being designated as the lectotype of each name, ARNAUD (1982a) simply said in a general statement that he considered syntypes labelled as “sp. figured” in the BMNH to be lectotypes of names established by BATES (1887). Nevertheless, as explained by EDMONDS (1994), the International Code on Zoological Nomenclature prohibits collective designation of lectotypes like ARNAUD (1982a) did. Indeed, the designation of lectotypes must be individual under Article 74.3 ( ICZN 1999). Consequently, all the lectotype designations for the BMNH specimens by ARNAUD (1982a) were invalid. Among the invalid lectotypes designated by ARNAUD (1982a) was that of P. coeruleus ( Figs 13 , 47 ).

BATES (1887) did not provide information on the size of the type series of P. coeruleus . However, he explicitly cited HAROLD (1863) to describe P. coeruleus . HAROLD (1863) commented that he examined only one specimen from Sallé’s Collection. Since BATES (1887) also relied in part on Sallé’s material, it is very likely that both referred to the same specimen. Consequently, that specimen should be considered the holotype of P. coeruleus by original monotypy ( Figs 13 , 47 ).

EDMONDS (1994) considered P. coeruleus ( Figs 13 , 47 ) to be a junior subjective synonym of P. daphnis ( Figs 11–13 , 35 , 46 , 57 ). The results of the present study suggest that P. coeruleus deserves full species status because it has a unique combination of characters: the posteromedial process of pronotum is produced into a denticle that is more truncate apically and more widened at the base in P. coeruleus ( Fig. 47 ) than in P. daphnis ( Fig. 46 ), while the elytral interstriae I–V are smooth in P. coeruleus ( Fig. 13 ). It is curious that the same differences had already been noted by HAROLD (1863), who regarded the single specimen that he examined as an odd individual of P. daphnis , and by BATES (1887), who treated coeruleus as a variety of P. daphnis . In addition, the dark blue colour with turquoise sheen on the whole dorsal surface of P. coeruleus ( Figs 13 , 47 ) differs from the dark blue to black colouration of P. substriolatus ( Figs 14–15 , 48 , 58 ), while the elytral striae are distinctly impressed in P. coeruleus ( Figs 13 ) but superficially impressed to partially erased in P. substriolatus ( Figs 14–15 ).

The only one specimen of P. coeruleus known to us is the holotype ( Figs 13 , 47 ). The labels of this specimen indicate that it was collected from Puebla, without specific locality ( Figs 13 ). Interestingly, none of the revised specimens from Puebla where identical in morphology to P. coeruleus . Since Phanaeus dung beetles from Puebla are scarcely studied (MORÓN et al. 2003), future intensive collecting is needed in this Mexican state to improve the knowledge of P. coeruleus and related species (e.g., P. herbeus and P. substriolatus ).

Distribution. Mexico: Puebla.

Figures

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

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 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.

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 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.