Onthophagus santamariensis Moctezuma, Sánchez-Huerta & Halffter, 2020

Moctezuma, Victor, Sánchez-Huerta, José Luis & Halffter, Gonzalo, 2020, Two new species of the Onthophagus clypeatus species group (Coleoptera: Scarabaeidae: Scarabaeinae), Florida Entomologist 103 (2), pp. 281-287 : 284-286

Onthophagus santamariensis Moctezuma, Sánchez-Huerta & Halffter new species ( Fig. 3 ).

TYPE LOCALITY

Santa María Chimalapa, municipality of Santa María Chimalapa, state of Oaxaca, Mexico.

TYPE MATERIAL (1 male, 6 females)

HOLOTYPE, male: “ México, Oaxaca, Santa María Chimalapa, 15/ VII/2016, coprotrap t24c19, 16.923944°N, 94.636638°W, potrero, 264 m, Victor Moctezuma Col” (Colección Entomológica Miguel Ángel Morón, Instituto de Ecología A. C., Xalapa, Veracruz, Mexico). PARA- TYPES: 1 female, same data as holotype except: “ Cerro Azul, c5, 12/ VI/2015, 16.872611°N, 94.717472°W, selva mediana, 243 m ” (Victor Moctezuma Collection, Xalapa, Veracruz, Mexico); 1 female, same data except: “ San Francisco La Paz, 12/VI/2016, t22c27, 17.102944°N, 94.065555°W,selva alta, 321 m ” (Colección Entomológica Miguel Ángel Morón, Instituto de Ecología A. C., Xalapa, Veracruz, Mexico); 1 female, same data except: “t22c24, 17.103444°N, 94.066361°W, 297 m ” (José Luis Sánchez-Huerta Collection, Xalapa, Veracruz, Mexico); 1 female, same data except: “t22c19, 17.103194°N, 94.067916°W, 269 m ” (Victor Moctezuma Collection, Xalapa, Veracruz, Mexico); 1 female, same data except: “ 14/VI/2016, t19c01, 17.079638°N, 94.090000°W, 113 m ” (Texas A&M University Insect Collection, College Station, Texas, USA); 1 female, same data except: “t19c06, 17.078305°N, 94.091333°W, 132 m ” (Gonzalo Halffter Collection, Instituto de Ecología A. C., Xalapa, Veracruz, Mexico).

ETYMOLOGY

The specific epithet derives from Santa María Chimalapa, the municipality where the type series was collected.

MALE

Holotype major male ( Fig. 3a ). Length: 5.5 mm, pronotal width: 3 mm, elytral width: 2.8 mm. Dorsal surface dark metallic red in color with a greenish cast, glabrous, reticulate microsculpture. Head: hexagonal in shape. Clypeus narrowly rounded anteriorly, distinctly reflexed. Clypeal punctures weakly marked. Frons concave with weakly marked punctures variable in size. Clypeal and frontal carinae lacking. Clypeogenal sutures well marked. Genae obtusely triangular with coarse punctures. Two elongate, slightly inwardly curve, slender cephalic horns rising behind the eyes. Pronotum: 2 longitudinal, dorsally acute, well defined tubercles in front of disc; tubercles well separated by a shallow concavity. Anterior half of pronotum with 2 concavities. Weakly marked, minute, sparse punctures in the antero-central portion of the pronotal disc, becoming coarse, dense, large and ocellate in the rest of the pronotum. Lateral fovea inconspicuous, irregular in shape. Elytra: elytral striae well marked; with coarse, ocellate, variably sized and regularly spaced punctures. Interstriae with minute punctures. Pygidium: coarse, dense, ocellate punctures, becoming smaller and less dense towards the apex, with dense, short, thick setae. Protibia: quadridentate on external border, lacking projections on internal border and apex. Apex with a dull, short setal brush. Parameres: apex strongly projected frontwards, obtusely triangular; apical teeth acute, well developed ( Fig. 3c ). Lamella copulatrix: inferior right lobe much longer than the lef lobe ( Fig. 3d ).

FEMALE

Differs from male by the head pentagonal in shape, clypeus reflexed and weakly sinuate, clypeal carina well marked, frons with 2 rounded transversal tubercles, pronotum uniformly punctate with coarse and ocellate punctures, anterior margin of pronotum with 2 almost indis- tinct concavities, and last abdominal sternite widened ( Fig. 3b ). The ventral portion of the vagina is well sclerotized ( Fig. 3e ).

VARIATION

Mean length: 4.9 mm (5.5– 4.6 mm), mean pronotal width: 2.9 (3.1– 2.5 mm), mean elytral width: 2.5 mm (2.8– 2.1 mm). Some paratypes are completely dark metallic red in color, lacking the greenish shine.

DISTRIBUTION AND ECOLOGY

Onthophagus santamariensis was collected in Subtropical Oak Forest fragments surrounded by pastures, and Tropical and Subtropical Rainforests between an elevation range of 100 to 400 m, a mean temperature of 22 to 24 °C, and an annual rainfall of 1,500 to 3,000 mm, from Los Chimalapas region, eastern Oaxaca, Mexico ( Fig. 2 ). The new species follows a Typical Neotropical distributional pattern ( Halffter & Morrone 2017), and may occur in Veracruz and Chiapas. Onthophagus santamariensis was collected with pitfall traps baited with human dung. Species in the Onthophagus luismargaritorum Delgado ( Coleoptera : Scarabaeidae ) species complex are frequently attracted to dung and carrion ( Delgado 1995; Delgado et al. 2006).

DIAGNOSIS

Onthophagus santamariensis and O. luismargaritorum seem to be closely related species. The new species may be distinguished easily by the acute longitudinal tubercles of the pronotum, separated by a shallow concavity in major males (rounded longitudinal tubercles, separated by a deep longitudinal concavity in major males of O. luismargaritorum ), and the apex of parameres strongly projected anteriorly and obtusely triangular (dorsally concave, not strongly projected anteriorly, irregular in shape in O. luismargaritorum ).

REMARKS

Onthophagus luismargaritorum , O. santamariensis , and Onthophagus yucatanus Delgado, Peraza & Deloya ( Coleoptera : Scarabaeidae ) share several characters that distinguish them from the remaining taxa of the O. clypeatus species group: the reduced size; clypeus obliquely reflexed and narrowly rounded; not strongly elongate, cephalic horns rising between the eyes; protibia short and wide; and female pronotum without tubercles ( Delgado et al. 2006). These 3 species are proposed by us in a preliminary manner to conform to the O. luismargaritorum species complex.

Figures

Fig. 3. Onthophagus santamariensis new species: (a) male dorsal habitus; (b) female dorsal habitus; (c) aedeagus; (d) lamella copulatrix; (e) vagina.

Fig. 2. Distribution of Onthophagus istmenus (white triangles) and Onthophagus santamariensis (black squares).