Aegidium simplex Frolov & Akhmetova, 2021

Frolov, Andrey V. & Akhmetova, Lilia A., 2021, A new species of Aegidium Arrow (Coleoptera: Scarabaeidae: Orphninae) from Colombia, Zootaxa 4927 (4), pp. 583-586 : 583-585

Aegidium simplex Frolov & Akhmetova , new species

Figs. 1–9 .

Type material. Holotype, male: “ Columbia Dr. Will. ” ( ZMHUB) . Paratype, female with the same data as for holotype ( ZMHUB) .

Description. Holotype, male ( Fig. 1, 3 , 5–9 ). Body length 10.9 mm, width of elytra 5.2 mm, width of pronotum 4.8 mm. Upper side of body shiny, color uniform brown, head and pronotum slightly darker.

Clypeus symmetrical with slightly convex anterior margin and rounded anterior angles. Head surface densely punctate with round punctures separated by less than a puncture diameter on clypeus, becoming denser and coarser on frons near eyes. Head without traces of medial horn or tubercle. Mandibles symmetrical, protruding past anterior margin of clypeus. Labrum rounded, small, slightly protruding past clypeus (in dorsal view).

Pronotum 1.5 times wider than long, widest at middle. Anterior margin with a border interrupted medially by a tubercle. Lateral margins crenulate. Base bordered. Disc of pronotum slightly depressed in middle. Surface densely punctate, punctures separated by about a diameter on disc, becoming denser towards sides.

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

Elytra moderately convex on disc with maximum width approximately at middle. Humeral and apical humps distinct. Elytra with 1 feebly distinct longitudinal ridge on disc between suture and humeral hump. First (sutural) elytral interval almost not elevated. Striae indistinct. Elytra densely punctate with coarse, irregularly shaped punctures not arranged in distinct longitudinal rows on disc. Base of elytra feebly bordered.

Wings fully developed.

Protibiae with 3 outer teeth and a smaller inner tooth. Lateral margin basad of outer teeth slightly crenulate. Apex and internal margin of tibia with a few slender setae. Protarsi about 1/2 length of protibiae. Claws 1/3 length of tarsomere 5, which is somewhat longer than tarsomeres 3 and 4 combined, and somewhat thicker than other tarsomeres. Tarsomere 1 as long as tarsomeres 2–4 combined. Ventral surface of femora punctate with rounded punctures.

Mesothoracic legs and metathoracic legs similar in shape; metafemora and metatibiae about 1.2 times longer than mesofemora and mesotibiae. Femora sparsely punctate with rounded punctures. Tibiae somewhat triangular, with two apical spurs. Mesotibiae without tuft of setae ventroapically ( Fig. 3 ). Upper tibial spur shorter than tarsomeres 1–3 combined; lower spur shorter than tarsomeres 1–2 combined. Claws 1/3 length of tarsomere 5, which is relatively slender, as long as tarsomere 2 and twice as short as tarsomere 1.

Abdominal sternites punctate with coarse irregularly shaped punctures. Sternite 8 medially about 2 times wider than sternites 4–7.

Pygidium triangular, convex, partly hidden under elytra, irregularly punctate with transverse punctures.

Aedeagus. Phallobase 2.1 times longer than parameres, tube shaped ( Fig. 5 ). Parameres reasonably wider than apical part of phallobase in dorsal view ( Fig. 6 ). Ventrobasal transverse plate of parameres absent ( Fig. 7 ). Endophallus without symmetrical strongly sclerotized sclerites ( Fig. 9 ). Cranial part of spiculum gastrale narrow, tapering and rounded at very apex ( Fig. 8 ).

Female. Female ( Fig. 2 ) differs from male in having a distinct protibial spur and relatively smaller pronotum without depression and anterior tubercle. Body length 12.0 mm, width of elytra 5.5 mm, width of pronotum 4.7 mm.

Differential diagnosis. In the key to the South American mainland Aegidium species ( Frolov et al. 2017b), the new species comes out in the couplet with A. reichei Preudhomme de Borre , A. bolivianum Frolov & Akhmetova , and A. varians Frolov, Akhmetova & Vaz-de-Mello. All these species are similar in having the mesotibiae without a tuft of setae ventroapically and in the lack of ventrobasal transverse plate of parameres. Aegidium simplex can be separated from these species by the parameres being wider in lateral view and the length/width ratio is approximately 2.0 (versus being narrower in lateral view and the length/width ratio being 3.5–4.0).

Etymology. From Latin, “ simplex ” for an ordinary appearance of the beetles.

Figures

FIGURES 1–4. Aegidium simplex, new species. 1, holotype male, habitus; 2, paratype female, habitus; 3, holotype male, mesotibia in ventral view; 4, holotype male, labels. Scale bar: 1 mm.

FIGURES 5–9. Aegidium simplex, new species, holotype, male. 5, aedeagus in lateral view; 6, parameres in dorsal view; 7, aedeagus in ventral view; 8, spiculum gastrale; 9, endophallus. Scale bar: 1 mm.