Vanonus aestiorum, Alekseev, Vitalii I. & Grzymala, Traci L., 2015

Alekseev, Vitalii I. & Grzymala, Traci L., 2015, New Aderidae (Coleoptera: Tenebrionoidea) from Baltic and Bitterfeld amber, Zootaxa 3956 (2), pp. 239-257 : 246-247

Vanonus aestiorum sp. nov. Alekseev & Grzymala

( Figs. 11 , 14–16 )

Material examined. Holotype No. AWI-037 [ CVIA], possible male ( Fig. 14–16 ). The beetle inclusion is preserved in a polished piece of transparent amber with a yellowish shade without any further fixation. The amber piece is parallelepiped, with maximum length 20 mm and maximum width 11 mm. The plant syninclusions are represented by ten trichomes.

Etymology. The species name is derived from the Old Latin names of the West Baltic tribes (Aestorum nationem, Aestiorum gentes, Hesti(s), Aesti/Aisti, Êstum).

Type strata. Baltic Amber. Eocene.

Type locality. Russia, the Kaliningrad region, the Sambian [Samland] peninsula, Yantarny settlement [formerly Palmnicken].

Description. Length 2.3 mm; moderately convex, elongate; uniformly dark gray. Upper surface biseriate, clothed in short pubescence, one seta arising anterad of each puncture, with additional numerous setae between primary pubescence (pruinose pubescence). Body length 2.9× maximum body width. Elytral length 1.4× pronotal length.

Head. Eyes large, oval, hemispherical, with distinct anterior emargination; well-separated from hind margin of head; interocular space about as wide as ocular diameter; temples approximately 1/5 of ocular diameter; apical maxillary palpomere broad, triangular, slightly rounded; apical labial palpomere wide, possibly subquadrate. Antenna filiform, robust ( Fig. 11 B); 11-segmented, pubescent; reaching basal third of elytra when folded backward; scape, antennomeres III and antennomere XI longest; antennomere length ratios: 10-4-8-5-5 -5-5- 5-5-5- 10.

Thorax. Pronotum ( Fig. 11 A) transverse, broadest anterad of middle; finely, densely punctate; with very fine and short simple pubescence, with three faint basal pronotal impressions. Scutellum trapeziform, widest at base. Elytron pubescent, with primary and interstitial setae, moderately convex, slightly depressed on disc in basal third; sides weakly rounded; width 0.55× length; punctation irregular, moderately dense.

Abdomen. Separation of abdominal ventrite I and abdominal ventrite II visible laterally, obsolete medially.

Legs. Metafemur slightly curved, with posterior brush of setae running length of metafemur, approximately 1/ 3× width of metafemur ( Fig. 16 ). Metatarsomere I approximately 2× metatarsomeres II-IV combined; metatarsomere II bilobed; metatarsomere III small and concealed.

Diagnosis. Vanonus aestiorum sp. nov. is similar in general appearance to V. ulmerigicus , and differs from it by the dense punctation of the pronotum, the scarce and almost invisible short pronotal pubescence, the form of the pronotal impressions (divided in three parts and more shallow), and the ratios of the antennomeres.

Figures

FIGURES 10 – 11. Vanonus spp. illustrations. 10) Vanonus ulmerigicus sp. nov. A. forebody, B. antenna, C. metafemur; 11) Vanonus aestiorum sp. nov. A. forebody, B. antenna.

FIGURES 12 – 16. Vanonus spp. habitus photographs. 12 – 13) Vanonus ulmerigicus sp. nov. 12) Holotype, lateral view; 13) Holotype, metafemur and abdomen, lateral view. 14 – 16) Vanonus aestiorum sp. nov. 14) Holotype, dorso-lateral view; 15) Holotype, lateral view; 16) Holotype, ventral view. Scale bars = 1.0 mm for 12 & 15, 0.5 mm for 14 & 16, 0.2 mm for 13.