Heterhelus (Heterhelus) buzina, Kupryjanowicz & Lyubarsky & Perkovsky, 2021

Kupryjanowicz, J., Lyubarsky, G. Yu. & Perkovsky, E. E., 2021, Heterhelus buzina sp. n. (Coleoptera: Kateretidae) from Rovno amber: the first proxy for Sambucus in the Eocene of Eastern Europe, Invertebrate Zoology 18 (1), pp. 16-24 : 18-21

Heterhelus (Heterhelus) buzina sp.n.

Figs. 1 , 2 .

HOLOTYPE. The specimen, in Rovno amber, deposited under accession number UCP No. 287. No syninclusions.

Type-locality: Klesov ( Ukraine).

DIAGNOSIS. Length 1.8 mm. Scape relatively small. Elytra exposing two complete abdominal tergites, elytral puncturation confused. Tarsal claws simple, without basal tooth.

DESCRIPTION. Body ( Fig. 1 : A, B) parallel-sided, convex, reddish-yellow, dully shining, covered with whitish setae. Head transverse and short, somewhat shorter than the distance between the eyes, densely punctate, punctures on disc smaller than the eye-facet, separated by 1-2 diameters ( Fig. 1C ). Antennal ( Fig. 1E ) insertions hidden behind projections of the frons; antennae 11-segmented with an indistinct 3- segmented, loosely articulated club. Antennae 1.1 times longer than the greatest width of the head, including eyes, with club 3-segmented; approximate ratio of segments: 31: 10: 7: 6: 7: 5: 6: 5: 9: 9: 12. Two apical segments are missing on the left antenna. Scape relatively small, elongated, not very long, 2.18 times long- er than its width. Eyes prominent, ocular setae absent. Labrum moderately arcuate ( Fig. 1C ). Terminal segment of labial palpus elongateoval ( Fig. 1D ).

Pronotum ( Figs. 1B ) convex, transverse, 1.5 times as wide as long; anterior margin slightly convex, anterior corner not prominent; anterior margin unbordered; lateral margin bordered; sides not explanate, not ciliate; basal margin indistinctly bordered, almost straight; punctures on disc similar in size to those on the head; posterior angles slightly obtuse.

Length of prosternum (excluding prosternal process) 1.17 times as long as the length of the mesoventrite, length of mesoventrite 0.5 times as long as the length of the metaventrite; prosternal process slender, subparallel-sided, apex truncate ( Fig. 1F ). Procoxae transverse, separated. Metaventrite convex, shining, densely covered with whitish or yellowish setae; punctures on disc about the same size as those on the head, separated by one diameter in the middle, becoming denser laterally ( Fig. 2A ). Mesocoxae and metacoxae widely separated, metacoxae not reaching the elytra at the sides. Inter-mesocoxal distance separated by 2.4 times the width of the inter-procoxal distance. Inter-metacoxal distance separated by 3.6 times the width of the inter-procoxal distance.

Six visible abdominal segments; abdominal segment 1 is the longest. Abdominal sternites shining; approximate ratio of length of abdominal sternites I–VI is 36: 10: 10: 23: 22: 8 ( Fig. 2B ); abdominal sternite VI short, the greatest width of the sixth abdominal sternite 5.5 times larger than the greatest length of the sixth abdominal sternite ( Fig. 2E ). Legs flattened; protibiae rather slender and short, shorter than the greatest width of the head, including the eyes. Tibia with a pair of spurs in the inner apical angle. Tarsi 5-5-5, with three basal tarsomeres subequal in length, strongly lobed. Tarsal claws simple, somewhat bulbous, but without a basal tooth ( Fig. 2C, D ).

Scutellar shield stout, triangular, apically rounded. Elytra truncated, exposing two complete abdominal tergites ( Fig. 2B ). Elytral disc diffuselypuncturated.Elytraconjointly1.2 times as long as wide, 2.2 times as long as the pronotum; punctures on disc larger and shallower than those on the pronotum. Abdominal tergite VI partially obscured by elytra. Abdominal tergite VII fully exposed, apex rounded.

ETYMOLOGY. Buzina is the Russian and Ukrainian name for Sambucus .

Figures

Fig. 1. Heterhelus buzina sp.n. (photo): A — total view, amber piece; B — total view, dorsal; C — head, in front; D — head, lateral; E — antenna; F — total view, ventral. Рис. 1. Heterhelus buzina sp.n., фото: A — общий вид ЯнтарЯ с включением; B — общий вид, дорЗально; C — голова спереди; D — голова сбоку; E — усик; F — общий вид, вентрально.

Fig. 2. Heterhelus buzina sp.n. (photo and drawing): A — meso- and metathorax, ventral; B — total view, lateral; C — tibia and tarsus II and III; D — claw; E — abdomen; F — total view, dorsal, line drawings. Рис. 2. Heterhelus buzina sp.n., фото и рисунок: A — средне- и Заднегрудь, вентрально; B — общий вид, латерально; C — голени и лапки II и III; D — коготок лапки; E — брюшко; F — общий вид, дорЗально.