Aegidium atlanticum Frolov, Grossi and Vaz-de-Mello, 2015

Frolov, Andrey V., Akhmetova, Lilia A. & Vaz-de-Mello, Fernando Z., 2017, Revision of the mainland species of the Neotropical genus Aegidium Westwood (Coleoptera: Scarabaeidae: Orphninae), Journal of Natural History 51 (19 - 20), pp. 1035-1090 : 1069-1071

Aegidium atlanticum Frolov, Grossi and Vaz-de-Mello, 2015

( Figure 8 (a–e))

Aegidium atlanticum Frolov, Grossi and Vaz-de-Mello, 2015: 437 .

Type locality

Brazil, Rio de Janeiro, Nova Friburgo, Macaé de Cima.

Type material examined

Holotype, male at CEMT labeled ‘ BRAZIL: RJ 1500 m Nova Friburgo Macaé de Cima 13. II.2000 P.Grossi’.

Diagnosis

Aegidium atlanticum is similar to Ae. peruanum sp. nov. in having a complex shape of the parameres with feebly sclerotised processes; this character separates both species from all other Aegidium species. From Ae. peruanum sp. nov., it differs in the shape of the paramere processes and in having a long, curved inner apical spur of mesotibia ( Figure 8 (b–d)).

Description

Male ( Figure 8 (a–d)). Body length 13.5 mm. Colour uniformly blackish brown.

Anterior margin of frontoclypeus almost straight, broadly rounded at sides, with a narrow, slightly upturned border. Frontoclypeus sparsely punctate with rounded punctures separated by 1–3 puncture diameters.

Eyes relatively large: width about 1/7 distance between eyes in dorsal view.

Pronotum with widely rounded lateral margins, narrower than elytra, 1.25 times wider than length, 0.5 times length of elytra. Posterior angles narrowly rounded. Anterior margin bordered, with a row of large punctures interrupted medially. Base of pronotum without furrow, punctate with a row of irregular, mostly elongate punctures. Pronotal disc slightly excavated. Lateral pronotal processes feebly developed, as low umbones. Pronotum irregularly punctate: with rather sparse, round punctures anterolaterally, somewhat coarser round punctures posterolaterally, irregular coarse punctures on disc.

Scutellum elongate, rounded apically, about 1/12 length of elytra.

Elytra 1.3 times longer than width, with humeral and apical umbones. Elytra widest in basal 1/3, slightly tapering apically in dorsal view. Elytral carinae distinct. Elytra densely punctate with coarse, irregularly shaped punctures arranged in longitudinal rows on disc.

Macropterous.

Mesotibiae without tuft of setae ventroapically. Inner apical spur of mesotibia longer than basal mesotarsomere and curved downwards ( Figure 8 (d)).

Aedeagus with relatively large (0.6 times length of phallobase, wider than phallobase in lateral view) parameres of complex shape: apices separated by a constriction and there are long feebly sclerotised processes basad of constriction on each paramere ( Figure 8 (b,c)). Ventrobasal transverse plate of parameres indistinct. Ventroapical part of phallobase deeply excavated, with concentric sclerotised carinae. Endophallus without strongly sclerotised sclerites.

Female . In CEMT, there is a female from Bahia State, Brazil, which may belong to this or to another, yet undescribed species. The specimen agrees with the holotype of Ae . atlanticum in its size and general appearance but the sculpture of the elytra is different: elytra are covered with rounded punctures separated by about 0.5 puncture diameters on disc and becoming slightly larger towards apices of the elytra. Additional material is needed to classify this specimen which was collected some 1000 km north of the type locality of Ae. atlanticum .

Distribution

Aegidium atlanticum is known from the Atlantic Forest ecoregion in south-eastern Brazil ( Figure 8 (e)).

Figures

Figure 8. Aegidium atlanticum, holotype male. Habitus in dorsal view (a), parameres in dorsal view (b), aedeagus in lateral view (c), apex of metatibiae (d), locality map (e).