Arnaudius bomansi Grossi and Bartolozzi

Grossi, Paschoal Coelho & Bartolozzi, Luca, 2011, Description Of A New Genus And Species Of Stag Beetle (Coleoptera: Lucanidae: Lucaninae) From The Peruvian Andes, The Coleopterists Bulletin 65 (4), pp. 387-392 : 388-392

Arnaudius bomansi Grossi and Bartolozzi , new species

( Figs. 1–3 , 6–8, 15 , 18 )

Type Material. Holotype male (dissected), labeled “ PERU: Huánuco / Paso Carpish / IX- 2006, 2850 m” // “ Arnaudius ♂ / bomansi n. sp. / Grossi and Bartolozzi 2011/ HOLOTYPUS ” . Holotype (ex collection L. Bartolozzi) deposited at Museo di Storia Naturale , Sezione di Zoologia “La Specola”, Firenze, Italy (collection number 15621) .

Description (Holotype). Body elongate, parallelsided, and weakly convex ( Fig.1 ). Length: 12.33 mm. Width: 4.25 mm. Color: Dorsal surface black, shiny, with some dark reddish lateral areas on elytra; ventrally dark, with coxae and femora dark reddish. Head: Shape transverse, disc weakly concave; laterally convex; surface moderately densely punctate; punctures of moderate size, becoming larger near internal eye margin; ocular canthi strongly expanded outwards, sub-quadrate, as wide as eye length. Mandibles as long as head, strongly upturned at apex; basal teeth weakly bilobed, directed forwards, laterally with a small, deep concavity; internal surface deeply concave, wide; apex bifurcated, apical tooth more developed and rounded, basal tooth angulate; dorsally with an inner acute tooth, followed by a erect tooth with apex slightly incurved; external and ventral surfaces punctate; punctures larger ventrally and with scattered setae. Pronotum: Shape transverse, as wide as head, convex, with obsolete longitudinal furrow, disc weakly concave; dorsal surface finely to moderately punctate; punctures larger near margins; each side of pronotum with 2 small depressions, the posterior one situated more externally; anterior border complete, above it with a strong triangular projection jutting out above head disc ( Figs. 2 and 3 ); anterior angles projecting and directed forwards and downwards (in lateral view); lateral borders crenulate and sinuate; posterior angles acute; posterior border sinuate. Scutellum: Triangular with rounded sides and moderate punctures at sides. Elytra: Elongate, longer than pronotum, head, and mandibles together, as wide as prothorax; each elytron with seven dorsal striae of large to coarse punctures; interstriae subcostate, moderately and finely punctate; humeri projected externally, rounded; elytral declivity strongly punctate; punctures coarse to coalescent. Legs: Anterior tibiae dentate externally; teeth increasing in size distally; mesotibiae with 4–5 external teeth, distal one larger, apex with 4 acute teeth around tarsal insertion; metatibiae with 2–3 external teeth of the same size as in mesotibiae; spurs acute, the dorsal one longer. Male genitalia: Genital capsule complex; dorsal plate lateral external lobes wide, internal lobes of bifurcation almost reaching each other, base of bifurcation with a subtriangular projection ( Fig. 6); ventral plate weakly sclerotized with scattered setae posteriorly ( Fig. 7); anterior projection almost 1/3 of ventral plate width. Aedeagus with parameres deeply incised ( Fig. 8); incision oblique, exceeding discal area; apex weakly rounded, somewhat prominent ( Fig. 15 ); median lobe expanded laterally, flat and wide at disc with posterior angles rounded and pronounced.

Female is unknown.

Etymology. We are very pleased to dedicate this new species to our friend and colleague Mr. Hugues E. Bomans (Montélimar, France), eminent specialist of Lucanidae , who contributed greatly to the knowledge of this family thanks to his dozens of papers.

Remarks. This species is closely related to A. koikei with which it shares the male prominent ocular canthi, which are almost square, while in A. digennaroi they are rounded. The pronotal shape is also similar in these species: in A. bomansi the anterior margin projects forward whilst in A. koikei it is just pointed, but evidently subtriangular. The anterior lateral margins of the pronotum are constricted in both species.

Arnaudius digennaroi (Arnaud, Noguchi, and Bomans, 2008) , new combination ( Figs. 4 , 9–11, 17 , 18 )

Remarks. This species was originally placed in Metadorcinus and the authors compared it to Metadorcinus yamauchii Arnaud, Noguchi, and Bomans, 2007 , but not with S. koikei , which was described one year earlier by the same authors (Arnaud et al. 2007) and has the same body shape. This species can be distinguished by the shape of the mandibles and canthi, by the male genitalia with the paramera slightly laterally lobate ( Figs. 11 and 16 ) and the uniquely shaped genital capsule ( Figs. 9 and 10), and by its different distribution. The only locality recorded for this species is Peru: Junín, Río Negro, Alto Perene.

Arnaudius koikei (Arnaud, Noguchi, and Bomans, 2007) , new combination ( Figs. 5 , 12–14, 17 , 18 )

Remarks. When describing this species in Sclerostomus , the authors did not mention or compare it to any other species. Apparently, very few specimens were collected and this species is only known from the type locality ( Peru: Cuzco, Cosnipata Valley). It resembles A. bomansi , especially in the shape of the male canthus, but can be distinguished from it by the different pronotal shape and male genitalia which possess a deep parameral lobe ( Figs. 14 and 17 ), shallower than that found in A. bomansi . The genital capsule also has a distinct shape ( Figs. 12 and 13), being more sclerotized and with the posterior bifurcation weakly lobate internally.

Figures

Figs. 1–5. Arnaudius spp. 1–3) A. bomansi (holotype male), dorsal view, head and pronotum in lateral view, head and pronotum in dorsal view, respectively; 4) A. digennaroi, head and pronotum in dorsal view; 5) A. koikei, head and pronotum in dorsal view.

Figs. 15–17. Arnaudius spp., right parameres in dorsal view. 15) A. bomansi; 16) A. digennaroi; 17) A. koikei. Scale = 2 mm.

Fig. 18. Map of the known distributions for the species of Arnaudius.