A new species of the genus Aegidium Westwood (Coleoptera: Scarabaeidae: Orphninae) from Peru

ABSTRACT A new species of Aegidium from Peru is described and illustrated. It can be recognized from its congeners by the shape of the parameres and spiculum gastrale, but also by the punctuation of the pronotum and the elytra. The species occurs in the Andean-Amazonian piedmonts from Peru.

PALABRAS CLAVE: Amazonia, región Neotropical, escarabajo escarabeídeo, taxonomía Aegidium is a fairly rare genus with little presence in collections, primarily due to the fact that the techniques commonly used to collect other scarabs, such as baited pitfall and light traps seem inefficient for species of Aegidium, which are occasionally collected with flight interception and Malaise traps.Here we describe a new species of Aegidium from Peru based on a single individual, which was collected using a flight interception trap.
The specimen is deposited in the entomological collection of Museo de Historia Natural de la Universidad Nacional Mayor de San Marcos -MUSM (Lima, Peru).The new species was contrasted against all described species in the genus, using the recent revisions of the genus by Rojkoff and Frolov (2017) and Frolov et al. (2017a), and posterior descriptions by Gasca-Álvarez and Deloya (2020) and Frolov andAkhmetova (2020, 2021).The terminology for the description follows Frolov et al. (2017a), and Frolov and Akhmetova (2020, 2021).Photographs were taken under a stereomicroscope Olympus SZ30 and the Zerene Stacker v.1.04.The images were cleaned and arranged using Photoshop 21.2.0.The distribution map was made using ArcMap 10.Description.Holotype.Male (Figures 1, 2).Length 13.2 mm; width 6.8 mm at middle of elytra, width of pronotum 6.6 mm.Coloration: Upper side of body shiny, color uniform blackish brown.Head (Figure 1d): without traces of medial horn or tubercle.Frontoclypeus with anterior margin straight, softly sinuate at the middle, rounded laterally.Head surface with oval to oval transverse coarser, contiguous punctures in the frons, especially near the eyes; otherwise, with smaller round punctures separated by 1 to 1.5 puncture diameter.Eyes relatively small: width about 0.125 distance between eyes in dorsal view.Labrum rounded, small and slightly protruding past clypeus in dorsal view.Pronotum: wider than elytra, 1.24 times wider than long.Anterior margin not bordered, posterior angles widely rounded.Base of pronotum not bordered, with a shallow irregular row of round punctures separated by less than 1 puncture diameter.Lateral margins crenulate.Surface of pronotum covered with rounded punctures more or less densely distributed, which are closer and have raised margins (crater-shaped appearance) in the entire anterior third (Figure 1b,d).Pronotal disc medially flattened and excavated, with lateral pronotal processes long, horn-shaped, and with a small horn medially on the anterior margin (Figure 1b,d).Scutellum: narrow, subtriangular, and rounded apically.About 0.062 length of elytra.Elytra: 1.12 times longer than wide, wider in the basal third and slightly tapering apically in dorsal view; with humeral and apical umbones.First elytral longitudinal carina feebly indicated basally, almost completely indistinct, second indistinct.Elytra covered with dense rounded to slightly oval elongated punctures, separated by 1 or less than 1 puncture diameter; slightly less dense over the sides.Posterior wings: fully developed, macropterous.Legs: femora sparsely punctate with rounded punctures.Anterior tibiae with four teeth laterally directed in the external face and distributed over the apical half, the basal one vaguely defined, almost obsolete; also, another tooth anteriorly directed is located in the inner anterior part of the anterior tibiae, over the protarsal and protibial spur insertion.Mesotibiae ventroapically without a tuft of setae (Figure 1e).Inner apical spur of the mesotibia longer than the first mesotarsomere, straight but slightly curved apically.First mesotarsomere as long as the combined length of the 2-4 mesotarsomeres.Mesotarsomere 4 shorter than mesotarsomere 5. Mesotibial claw 1/3 the length of the mesotarsomere 5. Abdominal sternites: covered with coarse, irregularly shaped punctures, in some cases, somewhat coalescent forming irregular lines of punctures, especially in the sternites 4-6 (Figure 1f ).Sternites 4-7 with a smooth area along the entire posterior edge; in contrast, sternite 8 with small punctures over the anterior edge and coarse punctures over the disc (Figure 1f ).Sternite 8 about twice as long as sternites 1-7 along midline.Pygidium: triangular, convex, and covered with densely distributed coarse punctures of irregular shape.Aedeagus: relatively short, parameres 0.49 times as long as phallobase (Figure 2a).Parameres slightly uneven (probably due to the extraction process), each apically rounded and slightly divergent between each other (Figure 2b).Parameres slightly wider than apical part of phallobase, lacking ventrobasal transverse plate (Figure 2a-c).Cranial part of spiculum gastrale narrow and tapering apically, subsquared in the apex (Figure 2d).Female.Unknown.
Variation.Only one specimen was available.
Diagnosis.Aegidium supai sp.nov. shares with a few other species the dense punctuation of the elytra (Figure  ACTA AMAZONICA 1a) and the absence of a ventroapically tuft of setae at the mesotibiae (Figure 1e), namely Aegidium bolivianum Frolov & Akhmetova, 2021, Aegidium geayi Paulian, 1984, Aegidium peresfilhoi Frolov, Akhmetova & Vaz-de-Mello, 2017, and Aegidium varians Frolov, Akhmetova & Vaz-de-Mello, 2017.According to the identification key for American mainland Aegidium species (Frolov et al. 2017a), the new species alligns with A. reichei and A. varians, and also with the recently described Aegidium bolivianum Frolov & Akhmetova, 2020 and Aegidium simplex Frolov & Akhmetova, 2021.These five species share the absence of a ventroapically tuft of setae at the mesotibiae and the lack of a ventrobasal transverse plate in the parameres.However, A. supai can be easily distinguished from A. reichei, A. varians, A. bolivianum and A. simplex by the almost completely indistinct elytral longitudinal carinae (Figure 1a,c), the crater-shaped pronotal punctures on the anterior third of the disc (Figure 1b,d), and the shape of the parameres and spiculum gastrale (Figure 2a-d).The combination of these morphological features distinguish A. supai from other species in the genus.
Etymology.The Quechua word supai means "devil".The specific name is based on the appearance of the specimen in frontal view as a devil with a pair of horns over its head (in reference to the pronotal horns) (Figure 1b).The specific epithet is a noun in the nominative case, standing in apposition.
Distribution.The specimen is known from a single locality near the city of Constitución, in Pasco Department, Peru, which corresponds to a very humid forest in the Andean-Amazonian piedmont (Figure 3).

Figure 1 .
Figure 1.Aegidium supai sp.nov.Holotype male.A -dorsal view; B -frontal view; C -lateral view; D -head in dorsal view; E -mesotibia in ventral view; F -abdomen in ventral view.Scale bars: 2 mm.This figure is in color in the electronic version.

Figure 2 .
Figure 2. Aegidium supai sp.nov.A -aedeagus in lateral view; B -parameres in frontal view; C -parameres in ventral view; D -spiculum gastrale.This figure is in color in the electronic version.