Acanthoglyptus picollus, Alekseev & Vitali, 2020

Alekseev, Vitalii Igorevich & Vitali, Francesco, 2020, Description of the first extinct member of the tribe Anaglyptini (Coleoptera: Cerambycidae) from European Tertiary, Zootaxa 4816 (1), pp. 135-143 : 137-141

Acanthoglyptus picollus sp. nov.

( Figs. 1–5 )

Type strata. Baltic amber, Blaue Erde deposits, Cenozoic: mid-Eocene to Upper Eocene .

Type locality. Yantarny settlement (formerly Palmnicken), Sambian (Samland) Peninsula, Kaliningrad Region, Russia .

Type material. Holotype: MAIG 6080 , adult. Sex: female. The specimen is included in narrow and long, orange-yellow amber piece with approximate dimensions of 42×7× 5 mm and preserved without supplementary fixation. It lacks the abdomen (only imprint on amber are available), the middle left leg, except for the coxa and the left hind leg. Syninclusions are represented by few stellate fagacean trichomes.

Description. Total body length about 9.0 mm; maximum length of pronotum 2.1 mm; pronotal maximum width 1.6 mm; length of an elytron along suture 5.2 mm; maximal width of elytra 2.5 mm; length of antenna about 8.0 mm.

Frons densely, finely punctate; longitudinal furrow reaching posteriorly the vertex; genae slightly emarginate anteriorly; distance between antennal tubercles wider than distance between inner margins upper eye lobes; posterior area of head, finely transversely wrinkled dorsally and laterally. Scape slightly curved, covered with recumbent sparse setae; pedicel as long as wide, less than one-third as long as scape; antennomere III slightly shorter than scape (excluding apical spine); antennomeres IV-VII with same length, as long as scape; antennomere VIII three-fourth as long as scape; antennomere IX slightly shorter than VIII; antennomeres X-XI with same length, two-thirds as long as antennomere III; antennomere proportions according to the formula: 1.6: 0.5: 1.5: 1.6: 1.6: 1.6: 1.6: 1.2: 1.1: 1.0: 1.0.

Pronotum about one-third longer than wide; disc covered with long, erect, sparse dark setae, and large, shallow punctures separated by about 2–3 times their diameter; sides, base and middle with dense, recumbent light pubescence, and very fine, dense punctation. Scutellum elongate, densely covered with light recumbent pubescence.

Elytra about 2.1 times as long as wide and about 2.5 times as long as pronotum; disc covered with moderately sparse, rounded punctures, irregular and deep on basal half (distance between punctures about 1–3 times diameter of each puncture), obliterate on apical half; each puncture bearing long erect or semirecumbent dark seta; dense light pubescence forming: 1) transverse, angulate macula laterally on basal quarter of each elytron; 2) inverted V-shaped median band; 3) apical spot on sutural angle.

Ventral side not completely conserved; prosternum, meso- and metaventrite finely punctate; metanepisternum narrow and long (about five times as long as wide); metaventral process three times narrower than mesocoxa; metaventrite with long, fine metathoracic discrimen; abdominal ventrites finely punctate, bearing long, erect, sparse setae apically; pygidium broadly rounded at apex; intercoxal process narrowly triangular; ventrites proportions (measured laterally) according to the formula: 3.0: 2.0: 2.0: 2.0: 1.5.

Metatarsomere I about 1.8 times as long as metatarsomeres II and III combined (or 1.1 times as long as tarsomeres II–IV together).

FIGURE 6. Distribution of the tribe Anaglyptini in Recent world (green area), Yoshiakioclytus (yellowish green area), and Acanthoglyptus picollus gen. et sp. nov. (red dot).

Etymology. The name of the new species is a theonym derived from Picollus (Peckols, Pockols, or also sometimes Patolls, Patulas, Patollo), the name of the Old Prussian god of the underworld and the easy death. The species name is a noun in apposition.

Remarks. The body integument coloration and colors of the dorsal pattern of the new fossil species are unknown.

Figures

FIGURES 1–2. Acanthoglyptus picollus gen. et sp. nov., holotype: 1—habitus, dorsolateral view; 2—forebody, dorsolateral view. Scale bars represent 2.0 mm.

FIGURES 3–4. Acanthoglyptus picollus gen. et sp. nov., holotype: 3—habitus, ventrolateral view; 4—body, dorsolateral view. Scale bars represent 2.0 mm.

FIGURE 5. Reconstruction of Acanthoglyptus picollus gen. et sp. nov. from Baltic amber. Habitus, dorsal view.