Onthophagus hircus Billberg, 1815

Rossini, Michele, Vaz-De, Fernando Z. & Zunino, Mario, 2018, Toward a comprehensive taxonomic revision of the “ hirculus ” group of American Onthophagus Latreille, 1802 (Coleoptera, Scarabaeidae, Scarabaeinae), European Journal of Taxonomy 432, pp. 1-21 : 6-9

Onthophagus hircus Billberg, 1815

Fig. 2A–B, D–E

Onthophagus hircus Billberg, 1815: 274 .

Onthophagus hirculus Mannerheim, 1829: 39 , syn. nov. ( Fig. 2C, F )

Regarding O. hirculus Mannerheim, 1829 , we found one female specimen at MZH whose original labels ( Fig. 2F ) led us to consider this singleton as a syntype of this species name. Indeed, the “Ménétr” label refers undoubtedly to the French ornithologist and entomologist Edouard Ménétriés. From December 1823 to January 1824, Ménétriés was recruited by Baron G.H. von de Langsdorff to collect specimens around Tijuco (Minas Gerais) and particularly across the Serra da Lapa ( Mannerheim 1829; see also Papavero 1971). Although Mannerheim in the original description of O. hirculus does not mention whether the specimens of the type series were collected by Ménétriés, he says the specimens were collected in Tijuco, which surely refers to the Arraial do Tejuco, the former name of the current municipality of Diamantina, Minas Gerais. According to Papavero (1971), the material collected by Ménétriés, de Langsdorff and Moritz Rugenda (the artist of the expedition) was partly sent to the Museum of Berlin, while 6 boxes of natural history specimens were sent to the Academy of Science of Saint Petersburg. The specimens belonging to the type series of O. hirculus were then incorporated into Mannerheim’s personal collection, which is today deposited at MZH ( Horn et al. 1990).

While the description of O. hirculus was based on at least one male and one female, we have so far not been able to find any male specimen attributable to the type series.

Thus, to preserve the nomenclatural stability for these species names, we designate as the lectotype of O. hircus the male belonging to the syntypic series, while the female is labelled as paralectotype. The only known surviving type specimen of O. hirculus is here designated as lectotype.

Material examined

Lectotypes ( here designated)

BRAZIL: ♂, Onthophagus hircus ( NHRS), [ Rio Janeiro , Kymell . (handwritten on white label)], [NHRS- JLKB 000021091 (printed on white label)], [LECTOTYPE, Onthophagus hircus Billberg , des. F.Z. Vazde-Mello, 2013, ♂ (printed and handwritten on red label with black border)].

BRAZIL: ♀, Onthophagus hirculus ( MZH), [Ménétr. (printed in italics on white label)], [Brasilia, Minas Gerais (handwritten on cream label)], [♀ (handwritten on cream label)], [ Onthophagus hirculus Mannerheim, 1829 (printed on white label)], [ID code, http://id.luomus.fi/GL.581 (printed on white label)], [LECTOTYPE, Onthophagus hirculus Mann., 1829 , ♀, des. F.Z. Vaz-de-Mello, 2014 (printed and handwritten on red label with black border)] .

Paralectotype

BRAZIL: ♀, Onthophagus hircus ( NHRS), [Rio Janei., Kymell . (handwritten on white label)], [NHRS- JLKB 000021092 (printed on white label)], [PARALECTOTYPE, Onthophagus hircus Billberg , des. F.Z. Vaz-de-Mello, 2013, ♀ (printed and handwritten on yellow label with black border)].

According to these new nomenclatural arrangements, it is noteworthy to reconsider the name of the species group to which O. hircus belongs. Therefore, the hirculus group, as originally established by Zunino & Halffter (1997), is here renamed the hircus group.

Morpho-anatomical description of the hircus group

MEASUREMENTS. Small to large-sized species, body length 4–12 mm.

COLOUR. Body either evenly coloured (completely black, blue, brownish or dark green with strong greenish, blue or cupreous sheen) or pronotum and elytra of different colours (pronotum bronze, metallic green or dark brown, or pronotal disc metallic green or cupreous with sides yellowish, elytra black to dark brown, with paler or darker spots at the base, apex or middle, or elytral interstriae with alternate colours). Pygidium same colour as body or lighter, sometimes dark with paler spots. Ventral side of body black or reddish brown, some species with yellowish to brownish areas on sternites, metasternum, middle and hindfemurs. Tegument of the body either smooth or very finely microreticulated, shining to opaque and sericeous with greenish, bluish or silver iridescence, punctuation either simple and very fine or coarse and deep, some species with punctures associated with distinct granules and conspicuous setae.

HEAD. Margins strongly sinuated to evenly curved, clypeus trapezoidal, obtusely squared or triangular, genal and clypeal margins continuous or genae clearly expanded beyond clypeus (head margin notched at the clypeo-genal junction), clypeus weakly to strongly reflexed at middle, plate-like to acuminated and narrowly rounded. Male with fronto-clypeal carina entire or interrupted at middle, with transversal ridge or lacking any structure, male with frontal horns either shorter than upper side of pronotum or longer and widely curved. Horns simple, triangular, conical or clearly expanded at base (carinate), parallel to divergent, inclined backward or bowed forward at apex, some species with a central carina between horns. Head of female always with distinct fronto-clypeal carina, low or distinctly higher at middle, frons with carina between eyes, straight to feebly curved forward, depressed, interrupted, inclined backward or with tubercle at middle. Articles of antennal club either normal or distinctly elongated.

THORAX. Posterior margin of pronotum with border evanescent near posterior angles,lateral margins evenly curved, either almost straight, but convergent or distinctly concave near anterior angles. Anteromedial pronotal protuberance of male widely rounded, triangular, squared, conical or shelf-like and horizontally extended above head, two specimens with a pair of tubercles on the anteromedial region. Dorsal side of protuberance distinctly depressed, flattened or evenly and slightly convex. Female with anteromedial protuberance of pronotum always transversal, curved, straight or widely concave at middle, with both sides simple or tuberculate. Elytral striae usually very shallow and interstriae flat to very weakly convex, interstrial punctuation fine and sparse or punctures aligned in two to three rows, often associated with small granules and pale setae. Anterior side of propleuron slightly excavated to convex, either simple or with a small and acuminated tubercle in proximity of anterior angles of pronotum. Metasternum simply swollen between mesocoxae or with longitudinal and short keel, metasternal tegument with stronger punctures near mesocoxae to finely and sparsely punctuated.

ABDOMEN. Pygidium always completely bordered, with a fine ridge carina-like between pygidium and propygidium, pygidial surface flattened to slightly convex, punctures of different sizes, strong to obsolete, sparse or well distributed, most of punctures associated with short and straight setae. Pygidial tegument often completely and finely microreticulated, sometimes microreticulation restricted to the basal region.

LEGS. Foretibiae of male slender and more elongated than those of female, apical and internal tooth either acuminate or blunt, apical margin of protibiae with a few straight setae, apical spur curved downward,

tip obtuse to acute, foretibiae always with four external teeth. Foretibiae of female unmodified, larger than those of male and not very elongated, external teeth stronger. Middle and hindlegs unmodified.

MALE GENITALIA. In lateral view, parameres either elongated or fairly short compared to length of phallobase, basolateral plate straight to strongly excavated at middle, distal-inferior paramerites either very feebly curved or strongly bent downward. In dorsal view, distal superior area of parameres with lateral margin evenly curved, obtusely angulate or strongly acuminate, anterior margin curved, sinuate or transversally truncated. In frontal view, lamella copulatrix with superior left lobe either clearly emarginated or transversally truncate on the external side, very reduced, narrow and elongated downward or very wide. Lateral margin of the superior left lobe normal to clearly bent inward, apex of lobe acuminated, obtuse and lobate or truncate. Inferior right lobe elongated downward and normal or short and with a distinct keel plate-like on the external margin. Medial keel of lamella copulatrix either wide or very reduced. Secondary lamella either squared with lateral margins parallel or very elongated and distinctly narrower at middle, superior side either normal or with a low keel.

FEMALE GENITALIA. Ventral sclerotization of vagina distinct to very weakly defined, central region wide to very narrow, with inferior margin either normal or distinctly sinuate. Distal portion of the infundibulum little developed in length.

Distribution

Species of the hircus group are distributed from the northern United States (Wisconsin according to Howden & Cartwright (1963); although the authors do not provide the exact locality, its position onto the map appears to be located far north with respect to the Canadian (mostly south of Toronto) and USA localities recorded in our study to central Argentina (San Luís Province), with the highest diversity across the Mexican Transition Zone, as well as the Brazilian and Chacoan sub-regions, which refer to the geographical space occurring from central and southern Mexico to most of continental South America ( Fig. 4 ).

Figures

Fig. 2. A–B. Dorsal habitus of the lectotype and paralectotype of Onthophagus hircus Billberg, 1815. C. Dorsal habitus of the lectotype of O. hirculus Mannerheim, 1829. D–E. Labels of the types of O. hircus Billberg, 1815. F. Labels of the type of O. hirculus Mannerheim, 1829.

Fig. 4. Geographical range of the hircus group.