Phanaeus pseudofurcosus 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 : 463-464

Phanaeus pseudofurcosus Balthasar, 1939 stat. rev.

( Figs 22–23 , 39 , 51 , 62 )

Phanaeus pseudofurcosus Balthasar, 1939: 244 . Type locality: Mexico, without specific locality.

Type material examined. MEXICO: HOLOTYPE: ♂ (originally designated by BALTHASAR 1939, examined from photographs; Fig. 23 ), without specific locality ( NMPC: Mus. Nat. Pragae Inv. 26350).

Non-type material examined. MEXICO: COLIMA: 8 ♂♂ 11 ♀♀, Comala ( IEXA). J AL I SCO. 3 ♀♀, Alista ( IEXA); 1 ♀, Alista, Presa La Tierra ( IEXA); 4 ♂♂ 2 ♀♀, Casimiro Castillo, El Tigre ( IEXA); 2 ♂♂ 1 ♀, Casimiro Castillo, La Calera ( IEXA); 2 ♂♂ 2 ♀♀, Casimiro Castillo, Rancho Piedra Bola ( IEXA); 1♂ 1♀, Cerro de García, San Luis Soyotlán ( VMPM), 1♀, El Corcovado ( IEXA);1♂ 3♀♀, La Manzanilla( GHVM); 2 ♂♂ 2 ♀♀, Sierra de Manantlán ( IEXA).

Diagnosis. Always metallic bright green ( Figs 22–23 , 51 , 62 ), occasionally with red sheen. Sides of pronotal disc granulate ( Figs 22–23 , 51 ). Pronotal disc coarsely granulorugose ( Figs 22–23 , 51 ). Posteromedial process of pronotum produced into narrowed denticle, short and distinctly emarginate apically ( Figs 39 , 51 ). Anteromedial portion of pronotal disc with two strongly developed denticles ( Fig. 51 ). Anterolateral margins of pronotal disc with line of tubercles; tubercles separated, never forming complete ridge ( Fig. 51 ). Posterolateral angles of pronotum much shorter than posteromedial process ( Figs 39 , 51 ). Elytral striae scabriculous, distinctly impressed, superficially punctate ( Figs 22–23 ). Elytral interstriae scabriculous, smooth, superficially punctate, convex ( Figs 22–23 ).

Variability. Minor male. Similar to major males, except for reduction of secondary sexual characters (i.e., cephalic horn, pronotal processes and posterolateral angles). Female. Similar to male, except for head showing trituberculate carina; pronotal sculpture granulate to superficially punctate, smooth or rugose posteriorly; pronotum with anteromedial black macula, and anteromedial carina followed by posterior concavity. The metallic bright green chromatic phase is more common in this species, but specimens with a red sheen are frequent ( Fig. 62 ).

Comments. EDMONDS (1994) erroneously applied the name P. pseudofurcosus ( Figs 22–23 , 39 , 51 , 62 ) to P. balthasari ( Figs 8–9 , 34 , 45 , 56 ), which he considered a subspecies of P. tridens ( Figs 1–5 , 32 , 43 , 55 , 63 ). Populations actually belonging to P. pseudofurcosus were classified in P. tridens tridens by EDMONDS (1994). Later, ARNAUD (2001, 2002) corrected EDMONDS’ S (1994) mistake in regard to the application of the name P. pseudofurcosus and transferred the Coliman and southern Jaliscan populations from P. tridens tridens to P. furiosus as the subspecies P. furiosus pseudofurcosus . A decade later, EDMONDS & ZÍDEK (2012) disagreed with Arnaud and returned those populations to P. tridens , now treated as a monotypic species (i.e., a taxonomically “homogeneous” species that does not comprise different subspecies according to ZACHOS 2016). Oddly, they said that P. pseudofurcosus was a junior subjective synonym of P. furiosus , not of P. tridens . This, as mentioned above, was likely a mistake and they meant to say that P. pseudofurcosus was a junior synonym of P. tridens .

Unlike previous authors, we conclude that P. pseudofurcosus – i.e., the southern Jaliscan and Coliman populations treated in P. tridens by EDMONDS (1994) and EDMONDS & ZÍDEK (2012) and in P. furiosus by ARNAUD (2001, 2002) – deserves full species status. Phanaeus pseudofurcosus is endemic to the Pacific coast of Mexico along the western Trans-Mexican Volcanic Belt and the northern Sierra Madre del Sur in Colima and Jalisco ( Fig. 66 ), while P. tridens is found in the Gulf of Mexico coast in northern Veracruz ( Fig. 64 ). Among morphological differences, P. pseudofurcosus shows the posteromedial process of pronotum produced into a narrowed denticle, short and distinctly emarginate apically ( Figs 39 , 51 ; produced into a denticle, distinctly widened laterally, elongate and apically bifurcated in P. tridens , Figs 32 , 43 ).

Differences from P. furiosus include the posteromedial process of pronotum of major males medially narrowed in P. pseudofurcosus ( Figs 39 , 51 ; distinctly thick and not narrowed in P. furiosus , Figs 38 , 50 ) and the posterolateral angles of pronotum distinctly raised in P. pseudofurcosus ( Fig. 39 ; posterolateral angles obsolete in P. furiosus , Fig. 38 ). The green chromatic phases of P. pseudofurcosus ( Figs 22–23 , 51 , 62 ) and P. furiosus ( Figs 19, 21 , 50 ) are similar, but P. pseudofurcosus never shows a completely red ( Fig. 20 ) or dark blue chromatic phase ( Fig. 61 ) as P. furiosus does. Additionally, P. pseudofurcosus shows a green-red chromatic phase not seen in P. furiosus .

Distribution. Mexico: western Trans-Mexican Volcanic Belt, northern Sierra Madre del Sur, and the Pacific coast in Colima, Jalisco and Michoacán ( Fig. 66 ).

Figures

Figs 22–23.Phanaeus pseudofurcosus Balthasar, 1939, stat.rev.22 – male green phase;23 – 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 8–9.Phanaeus balthasari Arnaud,2001, stat.rev. 8 – male green phase;9 – holotype

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.63. Phallobase, parameres and endophallite copulatrix of the P.tridens species group. Scale bar = 1.0 mm.

Fig. 66. Predicted distribution of P. furiosus Bates, 1887 and P. pseudofurcosus Balthasar, 1939.

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.

Figs 19–21. Phanaeus furiosus Bates, 1887. 19 – male green phase; 20 – male red phase; 21 – lectotype and labels (by Mario Cupello, UFPR). Scale bar = 1.0 mm.