Onthophagus acernorus Moctezuma, Hernández, & Sánchez-Huerta, 2021

Moctezuma, Victor, Hernández, Benjamín, Sánchez-Huerta, José Luis, Navarrete-Heredia, José Luis & Martínez-Rodríguez, Pablo Antonio, 2021, Onthophagus acernorus (Coleoptera: Scarabaeidae: Scarabaeinae: Onthophagini) a new dung beetle species from Jalisco, Mexico, Zootaxa 5067 (1), pp. 122-128 : 122-128

Onthophagus acernorus Moctezuma, Hernández, & Sánchez-Huerta , new species ( Figs. 1–5 )

urn:lsid:zoobank.org:act:3AC33DB0-093F-4B86-8CEA-8A8F0243812

Type locality. Mexico, Jalisco, Talpa de Allende, 20°12’53.20”N, 104°45’16.88”W .

Description. Holotype major male ( Figs. 1–3 ). Sericeus black dorsally, without metallic sheen. Head. Dorsal surface densely and superficially punctate, with sparse setae. Clypeus concave, transverse. Clypeogenal suture superficially indicated. Genae rounded. Frons flat. Clypeal carina obsolete. Frontal carina trapezoidal, without tubercles. Pronotum. Pronotal punctures coarsely impressed; each puncture bearing a seta. Integument scabriculous; with sparse micropunctures. In dorsal view, anterior protuberance obtusely trapezoidal, medially transverse, and straight. Intermediate tubercles and apex of pronotal prominence aligned. Posterior tubercles situated on anterior half of pronotum. Anterior angles of pronotum acute, lateral angles rounded. Elytra. Striae distinctly impressed; with evenly spaced, rounded, superficially impressed punctures. Interstriae surface flat, superficially punctate; each puncture bearing a seta. Integument scabriculous.

Tergite VIII. Surface densely and superficially punctate, each puncture bearing a seta. Integument scabriculous. Legs. Protibiae slender and quadridentate; inwardly bent on apical third. Protibial apical spur obliquely curved ventrally. Genitalia. Apex of parameres obtusely trapezoidal.

Minor male. Unknown.

Female. Similar to the male except for the clypeus elongate; clypeal carina distinctly developed; frontal carina rounded; pronotal protuberance distinctly reduced; posterior tubercles located in the anterior portion of pronotum; protibia widened ( Fig. 4 ).

Variation. Mean length 9.2 (6.6–11 mm).

Type material examined. Holotype (male): MEXICO. Jalisco: “Talpa de Allende: Bosque estatal de Arce, NTP-80-6-calamar, 30-I/ 03-III-2016, 20°12’53.20”N, 104°45’16.88”W, 1786 m, Bosque Mesófilo de Montaña con bosque de Arce. P.A. Martínez-Rodríguez y J.L. Navarrete-Heredia Col. ” ( CZUG).

Paratypes (3 males, 11 females): MEXICO. Jalisco: same data as holotype (1 male, 4 females, CZUG; 1 male, 1 female, CMNC); “ México: Jalisco: Talpa de Allende: Bosque estatal de Arce, NTP-80-5-calamar, 03-III/ 08-IV-2016, 20°12’58.58”N, 104°45’21.21”W, 1750 m, Bosque Mesófilo de Montaña con bosque de Arce. P.A. Martínez-Rodríguez y J.L. Navarrete-Heredia Col. ” (4 females, CZUG; 2 females, VMC); “ México: Jalisco: Talpa de Allende: Bosque estatal de Arce, NTP-80-4-calamar, 30-I/ 03-III-2016, 20°12’58.58”N, 104°45’21.21”W, 1750 m, Bosque Mesófilo de Montaña con bosque de Arce. P.A. Martínez-Rodríguez y J.L. Navarrete-Heredia Col. ” (1 male, CZUG)

Distribution and ecology. The new species is found in the Jaliscan district subprovince, Sierra Madre del Sur province (sensu Morrone 2017), Jalisco, Mexico ( Fig. 5 ).

Etymology. The specific epithet is an adjective in the nominative singular referring to the maple forest where the species occurs. The forest is dominated by Acer binzayedii Vargas-Rodriguez.

Diagnosis. Major males of O. acernorus are easily distinguished from the members of the O. chevrolati species complex by the intermediate tubercles almost aligned with the apex of the pronotal protuberance (intermediate tubercles situated posterolaterally in related species, Figs. 1 , 6 ). Onthophagus acernorus ( Fig. 1 ) is morphologically similar to O. chevrolati ( Fig. 6 ), but it can be distinguished by the pronotum more coarsely and densely punctate and less pubescent. Moreover, O. acernorus is completely black dorsally, while specimens of O. chevrolati are typically brown or dark brown, and with or without green metallic sheen when observed under the microscope. The apical teeth of parameres are more acute and the inferior right lobe of the medial endophallite is more strongly developed and wavy in O. chevrolati ( Fig. 3 ).

The following addendum to the Onthophagus chevrolati species group identification key will accommodate Onthophagus acernorus (modified from Moctezuma & Halffter 2020).

12(11). Dorsal surface completely green, or brown with bright green sheen. Apex of parameres straight. Jalisco (environs of Quila)............................................................... O. viridichevrolati Moctezuma & Halffter, 2020

- Dorsal surface dark brown or black, without bright sheen. Apex of parameres trapezoidal ( Fig. 3 )..................... 13

13(12). Secondary pronotal tubercles situated posterolaterally ( Fig. 6 ). Dorsal surface dark brown, occasionally with olive green sheen. Apex of parameres distinctly trapezoidal ( Fig. 3C ). Guanajuato, Hidalgo, Mexico City, Mexico State, Michoacán, Morelos, Puebla, Querétaro, Tlaxcala, Veracruz ( Fig. 5 )......................................... O. chevrolati Harold, 1869

– - metallic sheen. Apex of parameres obtusely trapezoidal ( Fig. 3A ). Jalisco (environs of Talpa; Fig. 5 )............................................................... O. acernorus Moctezuma, Hernández, & Sánchez-Huerta , new species

Figures

FIGURE 1. Onthophagus acernorus holotype male (dorsal view).

FIGURE 2. Onthophagus acernorus holotype male (frontal view).

FIGURE 3. Onthophagus acernorus holotype male: A, aedeagus; B, medial endophallite and additional medial endophallite. Onthophagus chevrolati: C, aedeagus; D, medial endophallite and additional medial endophallite.

FIGURE 4. Onthophagus acernorus paratype female.

FIGURE 5. Distribution of the Onthophagus chevrolati species complex in central Mexico.

FIGURE 6. Onthophagus chevrolati male (dorsal view).