Altitatiayus Weinreich, 1960

Grossi, Paschoal C., 2009, Generic limits in South American stag beetles: taxa currently misplaced in Sclerostomus Burmeister (Coleoptera: Lucanidae: Lucaninae: Sclerostomini), Zootaxa 2139, pp. 23-42 : 29-30

Genus Altitatiayus Weinreich, 1960 , new status

Type species: Sclerostomus rotundatus Boileau, 1902 by original designation ( Weinreich 1960: 78).

Description. Length: 10.0 mm – 17.0 mm. Width: 4.5 mm – 7.9 mm. Head: Form as wide as pronotum; disc with central depression; surface smooth in males. In females, form shorter and narrower than width of pronotum; disc weakly depressed. Eyes of males not prominent, not visible dorsally in some species. Temporal process present in males; process rounded, not prominently projecting laterally beyond eye. Mandibles of males well developed, cylindrical in cross section, as long as or longer than head, strongly upturned with apices always bifurcated and incurved; internally armed with conical teeth; ventral surface glabrous (lacking ventral row of setae). Mandibles of females shorter than head, incurved with apices acute; dorsally with external margin carinate; internally with one strong flattened tooth near apex. Maxillae with lacinia shorter than galea; lacinia with apex hooked or not (always hooked in females); hooks sometimes present in both galea and lacinia in both sexes. Antennae with 10 antennomeres, geniculate. Scape as long as the rest of the antennae, somewhat curved with weakly developed apical groove. Club composed of 3 antennomeres, proximal 2 antennomeres of club with distal margin tomentose, distal antennomere with apical half tomentose. Pronotum: Form broad, in males wider than elytra combined, robust, convex, with lateral margin sinuous or convex, border complete or not. Anterior margin convex or concave, sometimes at middle weakly emarginate (males); simply convex in females. Anterior angles rounded to truncate. Surface smooth in males, more strongly punctate in females. Elytra: Form short (sometimes shorter than head and pronotal length combined), with sides subparallel, convex dorsally. Disc with striae not impressed, indicated by longitudinal lines of punctures; surface glabrous. Wings: Wings extremely reduced, never reaching more than five millimeters (brachypterous). Legs: Protibiae flattened, serrate with 4–5 well-developed external teeth, the two apical teeth being stronger and somewhat forward directed. Mesotibiae with 1 large, acute median tooth, 3 smaller teeth present in the first basal third. Metatibiae with 1 large, acute tooth at apex of basal third and with or without a proximal smaller tooth. Onychium elongate with 2 (rarely 3) bristles at apex. Abdomen: Form short, with abdominal length less than an elytral half; surface smooth, sparsely punctate, punctures small; fifth sternite rounded at apex, longer in females than in males. Male genitalia: Genital capsule and aedeagus simple (Figs. 2, 4). Internal sac permanently everted, never longer than aedeagus, with apex expanded and without papillae; internally with longitudinal strap-like sclerite and sometimes with two other dark, elongate, subparallel sclerites. Median lobe elongate with sides parallel or sinuous, anteriorly and posteriorly deeply emarginate, nearly as long as parameres. Parameres large, with setose apices; base with internal, curved, spine-like projection. Basal piece narrowing to base, sometimes abruptly.

Distribution. Brazil: Rio de Janeiro State (Itatiaia); Minas Gerais State (Itamonte and Passa Quatro).

Diagnosis. Brachypterous species. Body convex, robust, with general oval aspect in both sexes. Male head and pronotum distinctly broad, wider than both elytra together. Female head as wide as one elytral width, slightly convex and weakly punctate. Mandibles of males upturned with apices bifurcate; basal teeth well developed, lacking row of setae ventrally. Pronotum in both sexes without any projections or tubercles, almost smooth in males, sparsely punctate in females. Elytral surface serially punctate but without impressed striae; interstriae simple, not carinate. Male genitalia with permanently everted internal sac short, apex expanded; parameres entire, at base with a spinose, curved projection.

Remarks. The first species in this genus was described by Boileau (1902) in the genus Sclerostomus , as S. rotundatus . Ohaus (1929) described S. zikani , which was subsequently placed into synonymy with S. rotundatus by Didier (1931). Lüderwaldt (1931) later described Sclerognathus ruficollis . Weinreich (1960) included both species in his subgenus Altitatiayus . Since Weinreich’s revision, three more species have been described; two species are from the Itatiaia Plateau in Rio de Janeiro and the other from Passa Quatro in Minas Gerais. Altitatiayus godinhorum (Bomans & Arnaud) and A. dulceae (Bomans & Arnaud) are very closely related species with slender male mandibles with the apices narrowly bifurcated. Altitatiayus trifurcatus (Grossi & Racca-Filho) is known from a single male specimen and is unique in possessing a conspicuous frontal process and mandibles with three apical lobes.

Altitatiayus now includes five known Brazilian species that occur in the mountains of Rio de Janeiro and Minas Gerais at elevations greater than 2200 m. Nagel (1934) provided the only known biological information for Altitatiayus when he described the larvae of Altitatiayus ruficollis (Lüderwaldt) and noted that the larvae and adults were found together in a mixture of soil, mosses, and lichens inside cracks in the rocks at Agulhas Negras peak. It is possible that the other species of the genus have similar habits but this has not been observed.

Species of Altitatiayus will be treated in an upcoming revision by the first author, and are only listed here.