Cerhomalus petrovitzi, Frolov & Akhmetova, 2021

Frolov, Andrey V. & Akhmetova, Lilia A., 2021, Taxonomic revision of the Afrotropical scarab beetle genus Cerhomalus Quedenfeldt, 1884 (Coleoptera: Scarabaeidae: Orphninae), European Journal of Taxonomy 739 (1), pp. 36-50 : 42-43

Cerhomalus petrovitzi sp. nov.

urn:lsid:zoobank.org:act:A04DF237-5C78-4B76-BEDB-7453CCEAB827

Figs 3 , 5C , 6

Differential diagnosis

Cerhomalus petrovitzi sp. nov. is most similar to C. mechowi in having the ventral fossae on the apices of the parameres completely bordered ( Figs 1F , 3G ) and the apices right angled in lateral view ( Figs 1C , 3D ) but can be separated from it in having the widened part of a paramere (in lateral view) about two thirds the length of the paramere ( Fig. 3D ) and ventral fossa of a paramere longer and narrower ( Fig. 3G ).

Etymology

The new species is named after Rudolf Petrovitz (1906–1974), a German coleopterist.

Type material

Holotype DEMOCRATIC REPUBLIC OF THE CONGO • ♂; “MUSEE DU CONGO BELGE KISANTU P. Goossens ”; MNHN.

Paratypes DEMOCRATIC REPUBLIC OF THE CONGO • 2 ♂♂, 1 ♀; same collection data as for holotype; RMCA • 1 ♂; “MUSEE DU CONGO Belge [Kasaï-Occidental] (Don M. Corpentier)”; MHNG .

Other material

NIGERIA • 1 ♂; “ Nigeria W. Afr. / (Staudinger coll.) 1914-412.”; BMNH.

Description

Male, holotype ( Fig. 3 A–B, D–G)

Body length 20.1 mm. Colour uniformly brown to black.

Anterior margin of frontoclypeus somewhat rectangular, slightly convex in middle, bordered and slightly serrate in dorsal view ( Fig. 3A ). Frontoclypeus with a keel-shaped transverse process near anterior margin; height of keel about half its width. Surface of frontoclypeus almost smooth, with minute punctures. Eye tubercles feebly developed. Eyes rather large: width about 1/6 distance between eyes in dorsal view. Antennae 10-segmented.

Pronotum widely rounded laterally, as wide as elytra. Anterior border wide. Basal border narrow, keelshaped, separated from pronotal disc by deep groove with row of longitudinally elongated punctures. Pronotal disc with a rounded depression occupying more than half of the surface, somewhat rugose anteriorly. Most of pronotum surface covered with minute punctures separated by more than 3 puncture diameters. Anterolateral angles with much larger and denser punctures; posteriolateral angles with same punctures but in smaller numbers.

Scutellum subtriangular, narrowly rounded apically, about 1/10 length of elytra.

Elytra 1.1 times longer than wide, with distinct humeral humps. Elytra widest in middle, lateral margins almost parallel in basal half. First (sutural) stria distinct, as groove with row of punctures. Other stria before humeral humps as rows of round setiferous punctures. Striae laterad of stria 5 feebly distinct. Elytral intervals covered with minute punctures, somewhat sparser than those on pronotum.

Macropterous.

Abdominal sternite 8 medially longer than sternites 6 and 7 combined; sternite 6 about as long as sternite 7. Pygidium invisible from above, with slightly truncate apex. Plectrum triangular with rounded apex, wider than long.

Aedeagus. Ventral fossae on the apices of the parameres completely bordered, long and narrow ( Fig. 3G ); apices of parameres right angled in lateral view, its widened part (in lateral view) about two thirds the length of paramere ( Fig. 3D ).

Female

Female ( Fig. 3C ) differs from male in having a relatively smaller, convex pronotum without tubercles and only with a small depression medially, frontoclypeus with much smaller, low keel not bimodal apically, protibial spur, and pygidium with rounded apex. Body length 21.0 mm.

Variation

Body length of examined male paratypes varies from 17.0 to 22.5 mm.

Distribution

The species is known from western Democratic Republic of the Congo ( Fig. 6 ). The record from Nigeria is doubtful and need confirmation, therefore the specimen is not included in the type series.

Figures

Fig. 3. Cerhomalus petrovitzi sp. nov. A–B, D–G. Holotype, ♂ (MNHN). C. Paratype, ♀ (RMCA). A, C. Habitus in dorsal view. B. Labels. D. Aedeagus in lateral view. E. Parameres in dorsal view. F. Parameres in apical view. G. Parameres in ventral view. Scale bars = 1.0 mm.

Fig. 5. Cerhomalus spp., scheme of aedeagus in lateral view and parameres in ventral view. A. C. absconditus (Petrovitz, 1971). B. C. mechowi Quedenfeldt, 1884. C. C. petrovitzi sp. nov. D. C. quedenfeldti sp. nov. Abbreviation: va. phlb. sc. = ventroapical phallobase sclerite. Not to scale.

Fig. 6. Cerhomalus spp., distributional record map.

Fig. 1. Cerhomalus mechowi Quedenfeldt, 1884. A–F. Lectotype, ♂ (MNHN). G. Paralectotype, ♀ (MNHN). H–I. Paralectotype, ♂ (ZMHUB). A, G, I. Habitus in dorsal view. B, H. Labels. C. Aedeagus in lateral view. D. Parameres in dorsal view. E. Parameres in apical view. F. Parameres in ventral view. Abbreviation: va. phlb. sc. = ventroapical phallobase sclerite. Scale bars = 1.0 mm.