Firkantus storozhenkoi Manukyan, 2025

Firkantus storozhenkoi Manukyan , sp. nov.

( Figs 1–7 View FIGURE 1 View FIGURE 2 View FIGURE 3 View FIGURE 4 View FIGURE 5 View FIGURE 6 View FIGURE 7 )

Holotype. N. 8549, ♂, Baltic amber. Location : Kaliningrad region ( Yantarny , Russia). Deposited in the Kaliningrad Amber Museum ( Russian National Foundation for Paleontology of Baltic Amber ), Kaliningrad, Russia. Well preserved complete specimen. Syninclusions: “Stellate hairs” ( Quercus sp. according to Weitschat & Wichard 2002) . Holotype is located in triangular amber piece 25.0 x 8.0 x 4.0 mm ( Fig. 1 View FIGURE 1 ). The specimen sustained mechanical damage during handling, affecting the right fore- and midlegs. The cuticle is partially destroyed.

Diagnosis. The following characters confidently place this fossil in Pimplinae : a short and high pronotum, specific wing venation patterns, broad laterotergites, general habitus, etc. The placement of the genus Firkantus within Pimplinae was also supported by phylogenetic analysis ( Viertler et al. 2023). The specimen shares similarities with the fossil genus Crusopimpla Copylov, Spasojevic & Klopfstein, 2018 and extant genera Theronia Holmgren, 1859 and Xanthopimpla Saussure, 1892 in the presence of propodeal carinae. However, it differs from Crusopimpla in several features, notably a complete occipital carina and the elongated cell 2Cu in the forewing, which in our specimen is 2.4 × as long as width, compared to approximately 2 × as long as width in Crusopimpla . The described specimen exhibits complete propodeal areolation, whereas Theronia and Xanthopimpla almost invariably lack a basal transverse carina. Other diagnostic traits typical of Xanthopimpla and Lissopimpla —such as deep depressions on tergites T2–4 are absent in our specimen. F. storozhenkoi sp. nov. differs from F. freddykruegeri by the following combination of characters: aedeagus laterally depressed (vs. dorso-ventrally depressed in F. freddykruegeri ); parameres relatively small, their length exceeding only T7 and T8 (vs. surpassing most metasomal tergites in F. freddykruegeri ). Nervulus distinctly postfurcal; vein 1 Cu ~ 0.5 × as long as1 cu-a and ~ 0.3 × length of 1 M+ 1 Rs (vs. 1 M+ 1 Rs interstitial and 1 Cu absent in F. freddykruegeri ). In F. storozhenkoi sp. nov. hind wing vein 1 Cu longer than cu-a (vs. cu-a longer than 1 Cu in F. freddykruegeri ). Additional diagnostic characters are provided in the key below.

Description. Head. Face uniformly convex ( Fig. 2A View FIGURE 2 ), lateral margins parallel, height 1.3 × maximum width; face separated from clypeus by faint depression. Mandible distinctly bidentate with longitudinal groove between teeth; mandible 1.5 × as long as basal width, sharply tapered apically; basal mandibular width about 2.0 × apical mandibular width; upper tooth broad; lower tooth small and acute, sharply pointed; distance from eye margin to mandible ~3.0 × mandible basal width. Clypeus small, weakly convex, separated from face by shallow depression; apical margin lacking tubercles, denticles or projections. Maxillary palp presumably 5-segmented, labial palp 4- segmented. Labrum concealed, not protruding beyond clypeus. Ocelli distinctly elevated above frons surface, positioned far from occipital carina, distance from lateral ocellus to occipital carina 2.2 × ocellar diameter; distance from lateral ocellus to eye margin equal to ocellar diameter. Frons laterally bordered by thin carina bearing large punctate depressions. Occiput posteriorly abruptly declivous at ~ 90° angle. Genae uniformly convex. Scape relatively short, 1.4 × as long as width; pedicel as long as wide. Antenna with 27 flagellomeres ( Fig. 2B View FIGURE 2 ); first flagellomere 2.9 × as long as wide; subsequent flagellomeres much shorter, flagellomeres 2–10 1.2–1.4 × as long as wide; flagellomeres posterior to flagellomere 10 about as long as wide; apical flagellomere complete and conical; multiporous plate sensilla absent.

Mesosoma. Mesoscutum ( Fig. 2B View FIGURE 2 ) broad, transverse; carina along lateral margin of mesoscutum complete and reaching anterior end of scutellum; notauli moderately deep, convergently extending beyond midlength of mesoscutum. Mesopleuron convex; epicnemial carina complete. Mesopleural pit weak; episternal scrobe without curvature toward mesopleural pit; sternaulus absent; posterior transverse carina of mesopleuron complete. Scutellum ( Fig. 3B View FIGURE 3 ) carinated laterally only in anterior half. Metapleuron ~1.3 × as long as deep; pleural carina distinct, extending along entire length of metapleuron; submetapleural carina complete, its anterior section unmodified; juxtacoxal carina complete. Propodeum with well-developed carinae ( Fig. 3B View FIGURE 3 ); lateromedian and lateral longitudinal carinae present; anterior and posterior transverse carinae complete; carina extending from pleural carina to spiracle present; propodeal spiracle extremely small, barely discernible.

Legs. Fore leg ( Fig. 4A View FIGURE 4 ): Tibial apex with single curved spur. Tarsomeres 1–5 length-width ratios: 3.7, 1.7, 1.7, 1.4, 3.0; arolium not extending beyond claw apex. Mid leg with two spurs on tibia, spurs equal in length. Hind leg: coxa 1.6 × longer than deep; femur 3.0 × as long as wide; tibia weakly curved, bearing two equal-length spurs; tarsomeres 1–5 length-width ratios: 3.5; 1.7, 1.7, 1.4, 3.0; tarsomere 5 enlarged; claws large, simple; arolium short, not surpassing claw apex.

Fore wing ( Fig. 5A View FIGURE 5 ). Pterostigma 3.2 × as long as wide. Metacarpus (2 R 1 ) not reaching wing apex. Vein 4 Rs uniformly curved (non-sinuate), ~3.0 × length of r-rs. Vein 3 Rs extremely short. Areolet closed, irregularly pentagonal; vein 3 rs-m longest, 1.6 × as long as 2 rs, 1.3 × as long as 2+3 M, 2.6 × as long as 4 M. Vein 2 m-cu nearly straight, distinctly inclivous, likely with single median bulla. Vein 2 Rs+M weakly curved. Vein 1 Rs+M (ramulus) presumably present. Vein 2 CU 1.2 × as long as 1 M+ 1 Rs. Vein 1 Cu-a (nervulus) straight, distinctly inclivous, postfurcal, positioned far from 1 Rs+ 1 M. Vein 1 Cu ~0.5 × as long as 1 Cu-a and ~0.3 × length of 1 M+ 1 Rs. Postnervulus (3 Cu+ 2 Cu-a) weakly angulate near midpoint (3 Cu and 2 Cu-a subequal in length). Vein 4 Cu 1.3 × as long as 5 Cu. Vein 2 A ~2.4 × as long as 1 cu-a. Cell 2 R 1 3.4 × as long as wide, 2 Cu 2.4 × as long as wide .

Hind wing ( Fig. 5B View FIGURE 5 ). Vein 1 Cu 2.1 × as long as cu-a. Vein 1 Rs 0.6 × as long as rs-m,

Metasoma ( Figs 6–7 View FIGURE 6 View FIGURE 7 ). Cylindrical. T1 1.4 × longer than posterior width, parallel-sided; dorsolateral carina sharp, distinct, extending to tergal apex; spiracles at anterior 0.4 of tergite; glymma present; lateromedian carina complete, slightly converging anteriorly, parallel after anterior third of T1; laterotergite triangular, membranous, divided medially by longitudinal depression. T2 transverse, 0.7 × as long as T1. T2–T4 with weak subapical transverse depression; spiracles positioned above fold separating laterotergite. Aedeagus laterally compressed; parameres squamose, moderately large, 1.3 × as long as midwidth, longer than T7 and T8 and much shorter than T1–T6.

Coloration and sculpture. Body, legs and wing veins uniformly dark brown to black. Microsculpture: finely and uniformly punctate throughout. Pubescence: evenly distributed short setae.

Measurements. Heal length ~ 0.7 mm; mesosoma ~ 2.1 mm, metasoma ~ 3.2 mm. Fore wing length ~ 4.8 mm, width ~ 1.3 mm. Hind wing length ~3.0 mm.

Etymology. This new species is named in honor of the Russian entomologist, Prof. Sergey Yu. Storozhenko (Vladivostok, Russia).