Onthophagus bidentatus Drapiez, 1819 : 134

Rossini, M., Vaz-De-Mello, F. Z. & Zunino, M., 2016, More transcontinental mislabeling in the genus Onthophagus: d’Orbigny’s “ African ” Group 27 (Coleoptera: Scarabaeidae: Scarabaeinae), Zootaxa 4175 (5), pp. 494-500 : 496-498

Onthophagus bidentatus Drapiez, 1819: 134 ( Fig. 1 A, F)

Onthophagus bicornis Castelnau, 1840: 87 (fide Blackwelder, 1944: 211)

Onthophagus semichalcites d’Orbigny, 1902: 149 syn. nov.

Type locality: French Guyana: Cayenne.

Notes on ecology and distribution. This species appears to be very common in open habitats, rarely found in transitional forested areas.

Pulido-Herrera & Zunino (2007) mentioned O. bidentatus of Guadalupe, Colombia, Venezuela, Guiana, Brazil, Peru and Argentina. In our opinion, the Guadalupe specimens mentioned in Blackwelder (1944) may belong to O. antillarum Arrow, 1903 , which is undoubtedly a close relative of O. bidentatus . Furthermore, as already questioned by Martínez (1959), the occurrence of O. bidentatus in Argentina (Jujuy) ( Bruch, 1911) is still very doubtful. According to Bruch’s catalogue, the specimen/s is/are deposited in his personal collection at the Museo Argentino de Ciencias Naturales “Bernardino Rivadavia” (marked with an asterisk), but to date we could not examine this material.

Boucomont (1932) mentioned O. bidentatus of Callanga and Cuzco ( Peru: Cuzco) and the recent study of several natural history collections led us to confirm the occurrence of this species in Callanga (two males, NMPC), Machu Picchu (one male, MZc) and Puno (one male, MZc). Although we could not directly prove the presence of O. bidentatus in Cuzco, it seems quite reasonable to confirm this locality too.

New geographic records for O. bidentatus are Panama (Veraguas, Panama and Darién) , Trinidad and Tobago, Suriname (Paramaribo) and Ecuador (Napo and Zamora-Chinchipe). More details about the geographic distribution of O. bidentatus will soon be published in a revision of the hirculus group of the American Onthophagus .

Remarks. Drapiez (1819) described O. bidentatus from two specimens collected in Cayenne, French Guyana, and received by M. J. Baudet-Lafarge (hereafter referred to as BL), who used to exchange natural history specimens with entomologists and amateurs around the World. It is likely that BL received these specimens from Mr Banon, a pharmacist settled in French Guyana with whom he had correspondence (short essay from Baudet-Lafarge’s original manuscript of his collection of Coleoptera ). According to Drapiez (1819), BL named these specimens Onthophage bicorne (then latinized into Onthophagus bicornis ), although the French author never published even a short description of this species name, unless it was included in his rare manuscript (Description des insectes de ma collection).

Since the absence of cephalic horns to justify the epithet proposed by BL, Drapiez decided to replace this name with Onthophage bidenté (then latinized into Onthophagus bidentatus ) because of the characters observed in the pronotal protuberance: “ … nous n’avons point observé à la tête, d’organes qui justifiassent pleinement le nom de bicorne, nous nous sommes permis de lui substituer celui de bidenté, tire du caractère du corselet qui paraÎt constant; ” [… we have not observed organs that fully justified the name bicorne, so we permitted to replace it with bidenté, as the pronotal character seems to be constant] ( Drapiez, 1819: 134–135).

The name Onthophagus bicornis Beaudet-Lafarge (misspelling of the author name as mentioned in the original paper) is reported (with its var. violaceus Lacordaire and its synonyms inauratus Lacordaire and ovinus Lacordaire) by Dejean (1836).

In 1840, Laporte de Castelnau included Onthophagus bicornis Beaudet-Lafarge (misspelling of the author name as mentioned in the original paper) in his “Histoire Naturelle des Insectes Coléoptères”, along with a short description and bibliographic reference that refer undoubtedly to Drapiez’s work (“ Ann. des. Sc. phys., t. 1, p. 134, n. 13, pl. 7, Fig. 5. ”). Nonetheless, it is not clear whether Castelnau examined the type specimens of this species or just used the diagnostic characters provided by Drapiez (1819) to describe O. bicornis . Anyhow, as formerly proposed by Boucomont & Gillet (1927) and Blackwelder (1944), there is no doubt about the authorship of Castelnau on O. bicornis .

According to this information, it is conceivable to believe that O. bidentatus and O. bicornis refer to the same biological entity, as the respective descriptions are based on specimens belonging to the same type series. Thus, Onthophagus bidentatus Drapiez, 1819 possesses all the requirements to be accepted as valid name instead of Onthophagus bicornis Castelnau, 1840 ( ICZN, 1999: Art. 23).

During a recent visit to the MNHN we found a specimen whose labels and morphology matched exactly the diagnosis provided by Drapiez (1819) ( Fig. 1 A, F). It is very likely that this female is one of the two specimens donated by Baudet-Lafarge to the Belgian naturalist at the beginning of the 19th century. Therefore , considering that Onthophagus bidentatus Drapiez, 1819 and Onthophagus bicornis Castelnau, 1840 have been described on specimens belonging to the same type series, we decided to designate the lectotype of both species names on this single female specimen deposited in the R. Oberthür collection ( MNHN) ( ICZN, 1999: Art. 72.6; 74).

Type specimens examined. Of O. bidentatus and O. bicornis : Lectotype (♀ MNHN): 1: MUSÉUM PARIS, 1952, coll. R. OBERTHÜR (printed on white label with black border). 2: Bicornis Bd-Laf, Cayen., Typus! (handwritten in italic on cream label with black line at the bottom). 3: Cayenna (handwritten in italic on cream label). 4: LECTOTYPE, female symbol, Onthophagus bicornis Cast. , des. F.Z. Vaz-de-Mello, 2014 (printed and handwritten, on red label with black border). 5: LECTOTYPE, Onthophagus bidentatus Drap., M. Rossini 2016 (printed on red label with black border).

Of O. semichalcites : Lectotype (♂ MNHN): 1: Benin (handwritten on cream label). 2: Semichalcites d’Orb. (handwritten on cream label) . TYPE (printed on red label). 3: MUSEUM PARIS, Coll. H. d’ORBIGNY 1915 (printed on green label). 4: Espèce Américaine, Y. CAMBEFORT DET. (printed and handwritten on white label with black border). 5: LECTOTYPE, male symbol, Onthophagus semichalcites d’Orbigny , des. F.Z. Vaz-de-Mello, 2014 (printed and handwritten on red label). Paralectotypes (1 ♂, 5 ♀♀ MNHN): 1: Benin (handwritten on cream label). 2 : MUSEUM PARIS, Coll. H. d’ORBIGNY 1915 (printed on blue label). 3: PARALECTOTYPE, Onthophagus semichalcites d’Orbigny , des. F.Z. Vaz-de-Mello, 2014 (printed and handwritten on yellow label with black border).

Figures

FIGURE 1. Dorsal habitus and labels of the primary types. A, F: O. bidentatus and O. bicornis. B, G: O. striatulus. C, H: O. semichalcites. D, I: O. gibber. E, L: O. gibberosus. Scale bar: 1 mm.