Thraustocolus (Prothraustocola) clypealis, Wagner, 2023

Wagner, Gerhard, 2023, A new species and subspecies of the darkling beetle genus Thraustocolus Kraatz, 1866 from Oman (Coleoptera, Tenebrionidae), Evolutionary Systematics 7 (2), pp. 253-256 : 253

Thraustocolus (Prothraustocola) clypealis sp. nov.

Fig. 1

Material examined.

Holotype ♂: Oman, Al Heil , 12 km northwest of Al Hamra, 1960 m, 23°12'N, 57°12'E, 29.02.2020, leg. C. & G. Wagner. Paratypes: 1 specimen (sex unknown): Oman, Al Heil , 12 km northwest of Al Hamra, 1960 m, 23°12'N, 57°12'E, 23.10.2014, leg. C. & G. Wagner. - 2♂: Oman, Al Heil , 12 km northwest of Al Hamra, 1960 m, 23°12'N, 57°12'E, 19.03.2009, leg. C. & G. Wagner. - 1♀: Oman, 8 km northwest Sabikah , 23°10'N, 58°06'E, 06.03.2011, leg. C. & G. Wagner. - 2♀: Oman, Wadi Suwayh , 20 km south of Quriat, 23°05'N, 58°57' E, 08.03.2009, leg. C. & G. Wagner. - 1♂: Oman, Wadi Hatat , Al Amarat, 450 m, 23°22'55"N, 58°20'40"E, 13.12.2021, leg. J. C. Ringenbach. All type specimens listed above are currently kept by the author, later in Zoological Museum, Museum der Natur, Hamburg (ZMH). - 1♀: North Oman, Nizwa, Fira, 01.03.2003, leg. J.C. Ringenbach. - 1 specimen (sex unknown): Oman, Wadi Hatat , Al Amarat, 450 m, 23°22'55"N, 58°20'40"E, 13.12.2021, leg. J.C. Ringenbach , in Ringenbach Collection.

Description.

Measurements. Length: ♂ 9-10 mm, ♀ 9-12 mm, width: ♂ 3-4 mm, ♀ 3.6-5 mm.

General coloration. Black to brown-black.

Head. Strongly punctured, strigose on the side of frons, shagreened spaces between the punctures on the anterior half, smooth on the back. Eyes large, flat, rounded, but in front more straight bounded by the genae. Head slightly longer than wide, greatest width at the border of the eyes and temples, transition from temples to eyes without angles, from eyes to genae with a reentrant angle of a good 90°. Between the genae and the anterior border of the clypeus a strong, characteristic lateral emargination, clypeus trapezoidal, anterior border truncated, often slightly concave. Frons with two lateral, strong impressions. Between the impressions, clypeus separated from the frons only by a slight bead and from there running downwards to the anterior margin. Keels present above the eyes (Fig. 1b ).

Antennae. With a noticeably long 3rd segment, three times as long as the 2nd, the 4th half as long as the 3rd. From the 8th antennal segment to the 10th, becoming trapezoidally broader, the 11th shorter than the 10th. When directed backwards the antennae protrude beyond the base of the pronotum at about the 11th segment.

Pronotum. Very strong convex in length and width, shiny, lateral strong evenly rounded, slightly narrowing towards the base than towards the anterior border, thin margins all around, the right-angled anterior corners bent down, not visible in dorsal view. The posterior corners obtuse, and in contrast to the anterior corners, strongly rounded; pronotum dorsally roundly punctured all over, not confluent with shiny spaces of different sizes between one third and three times of a diameter of a puncture.

Elytra. Oval, less clearly punctured than the pronotum on a weak shagreened ground, often with fine transverse wrinkles. Basal margin present only on the shoulders (characteristic of the subgenus Thraustocolus Prothraustocola ).

Legs. Long; femora slender, tibiae thin, tarsi shorter than tibiae, the latter straight in females, in males especially the fore tibiae are more or less distinctly curved inwards. Metatarsomere 1 is longer than the next two tarsomeres together and is as long as metatarsomere 4.

Submentum. Starting from the base, widening straightly in the basal third, then narrowing straightly at a sharp, obtuse angle towards the anterior border. The anterior border with a strong round incision.

Gular sulcus not furrow-like, but consists of a pit in the middle that flattens out on the sides (characteristic of the subgenus Thraustocolus Prothraustocola ). Prosternum clearly punctured, male with a small deep rounded pit with a prominent bristle (Fig. 1c ). Propleurae with lines of punctures, prosternal apophysis behind procoxae initially descending vertically, then briefly protruding horizontally sharp-edged in a roof-like manner (Fig. 1d ). Mesosternum, metasternum and ventrites clearly punctured, spaces smooth.

Aedeagus. Slender, basal section almost as long as the apical, sides of the latter running parallel for about a quarter of its length, then uniformly very acute (Fig. 1e, f ).

Etymology.

The species is named after the peculiar formation of the clypeus.

Figures

Figure 1. a. Thraustcolus clypealis sp. nov. dorsal view; b. T. clypealis sp. nov. head and pronotum dorsal view; c. T. clypealis sp. nov. head and pronotum ventral view; d. T. clypealis sp. nov. procoxae with prosternal apophysis; e. T. clypealis sp. nov. aedeagus; f. T. clypealis sp. nov. aedeagus lateral.