Scarabaeus (Scarabaeolus) orientalis Zidek and Pokorný, 2018

Zidek, Jiri & Pokorný, Svatopluk, 2018, New species of the Scarabaeus subgenus Scarabaeolus Balthasar, with a review of the subgenus (Scarabaeidae: Scarabaeinae: Scarabaeini), Insecta Mundi 611, pp. 1-35 : 9-10

Scarabaeus (Scarabaeolus) orientalis Zidek and Pokorný , sp. n.

Fig. 47–50

Type locality. RSA, Transvaal, Frm: Rhenosterpoort.

Type material. HTm + 1 PTm , leg. L. Schulze 2.I.1976, meat trap; both types at TMSA.

Etymology. Eastern (Latin).

Description of holotype. Length 15 mm (both specimens). Black, semiglossy, ventrally with sparse yellowish pubescence.

Head. Clypeus finely longitudinally punctate, with teeth upturned, without ventral keel, spaces between them U-shaped, posteriorly with short rust-colored setae concentrated in a pair of ill-defined patches. Genae separated from lateral clypeal teeth by narrow fissures with rounded bases, anterolater- ally as punctate as clypeus; their lateral margins straight and sparsely setose, medially with a suture forming a low crest that defines gena/frons boundary but anteriorly ends in front of eye, leaving clypeus/ gena boundary incomplete; anterior tips curved out, posterior corners oblique. Frons and vertex largely effaced, only laterally with a few scattered coarse tubercles. Antennal club brownish yellow.

Pronotum. Bordered all around, lateral margins evenly rounded and crenulate, base with a weak medial lobe, front angles pointing forward, hind corners gradually merging into base; sagittal line present throughout length, broad, not impressed, defined only by absence of punctures; reminder of surface coarsely punctate, punctures unevenly distributed, spaces between them equal to or greater than puncture diameters, lateral of disc punctures more sparse to absent.

Scutellum . E xposed, small, triangular, impunctate.

Elytra. With striae deep, finely and densely punctate; intervals convex, punctate as coarsely as pronotum, punctures roughly aligned and not reaching interval margins, first interval only half as wide as following intervals; humeri obsolete, confined to sixth interval.

Pygidium . Semilunar, bordered all around, impunctate, shagreened.

Venter. Metasternum finely punctate throughout, with tip of anterior process rounded. Abdominal ventrites semiglossy, impunctate, with a few scattered tubercles near midline.

Legs. All tibiae and femora sparsely punctate and pubescent. Protibia without distal inward angulation, second tooth longest, fourth tooth shortest; space between first and second teeth equals that between second and third teeth, space between third and fourth teeth slightly shorter; lateral margin serrate between teeth as well as proximal of them, medial margin crenulate throughout length; spur slightly shorter than terminal seta. Meso- and metatibia each with two transverse carinae; mesotibia with one spur. Tarsi slender, with articles not markedly triangularly expanded, basal metatarsomere twice as long as preceding.

Aedeagus. With parameres and phallobase of equal lengths, left paramere in lateral view with only a minute ventral tubercle; paramere tips truncate, dorsally rounded and ventrally produced into short beaks.

Comparison. In 1993, zur Strassen examined the two specimens described here as a new species and identified them as S. palemo Olivier on external morphology alone, without extracting the aedeagus. External differences between S. palemo and S. orientalis sp. n. are mainly in elytral sculpture, which in some specimens of S. palemo is so coarse that punctures span the entire width of intervals, breaking them transversely and giving the elytra rugose appearance. This is merely an intraspecific variation, however, as are relative thickness of the metatibia or the degree of triangular expansion of the basal metatarsomere. The only reliable species-level character appears to be the aedeagus.

Figures

Figures 47–54. Scarabaeus (Scarabaeolus) spp. 47–50) Scarabaeus (Scarabaeolus) orientalis sp. n., HTm, 15 mm. 47) Dorsal habitus. 48) Ventral habitus. 49) Aedeagus, dorsal. 50) Aedeagus, left lateral. 51–54) Scarabaeus (Scarabaeolus) cf. bohemani / palemo, RSA, Limpopo Province, 14 mm. 51) Dorsal habitus. 52) Ventral habitus. 53) Aedeagus, dorsal. 54) Aedeagus, left lateral.