Medium sized to large (7–15 mm), slender, black lustrous Nematocera, often with lighter markings on thorax and/or abdomen. Antennae, wings, abdomen, and legs long and slender. Ocelli absent; antenna with 15 to 16 segments. Thorax with deep, posteriorly directed transverse suture. Wing with markings, in particular along the crossveins and where veins bifurcate; spurious vein present on either side of crossvein R-M and wing membrane with a distinct fold between veins A₁ and C_uA₂ (Oosterbroek 2006; Fasbender 2014).

Holotype : 1 ♂: Azerbaijan, Qum, sidebrook/small tributary of the Ardavacaj (Ardavachay) River + wetland, 845 m a. s. l., 41°28'10.3"N, 46°55'57.2"E, 8.V.2019, leg. J. Oboňa & P. Manko. Paratypes: 2 ♂♂: Georgia, border of Imereti and Samtskhe–Javakheti regions, brook and spring, south slope of Zekari pass, 2 050 m a. s. l., 41°49'23"N, 42°51'09"E, 17.VII.2019, leg. G. Vinçon.

Male. Head: Frons, vertex, and occiput black with metallic blue shine, mouthparts including palpi pale yellow, scape and pedicel yellowish orange, antennal flagellomeres a somewhat darker, tending to pale brown.

Thorax : Scutum, paratergite, and mediotergite blackish with metallic blue shine; scutellum, pleurotergite, katepisternum, and katepimeron brownish black with lighter metallic blue shine; other parts yellow. Halteres yellow with light brown knob. Legs yellow except brown extreme apex of femora and tibiae, tarsi somewhat darkened.

Wing length 10 mm (holotype, Fig. 1c). Wing almost hyaline, veins yellowish brown, distinct spots brownish black, forming more or less three stripes, at base of wing at the level of crossvein h, from C to Cu. Middle stripe touching vein C, running through cross-veins up to middle part of vein Cu, isolated spot before end of vein Cu. Isolated spot on around middle of R₁. Third stripe consist of three large, almost touching spots: at the tip of R₁ and fork of R₂+₃, one on fork vein R₄+₅ and one on fork vein M₁+₂. Small spot at the end of vein R₃.

Figure 1. 

Ptychoptera xanthopleura sp. nov. a habitus of male, lateral view b pleurae, lateral view c wing.

Abdomen : Tergum 1 dark shiny brown with yellow apex, sternum 1 yellow. Tergum 2 brown basally and apically, yellow in middle, sternum 2 yellow. Tergum 3 yellow basally, brown apically, sternum 3 yellow. Remaining terga and sterna brown, sternum 4 yellow basally. Auxiliar copulatory organ yellow.

Male genitalia (Fig. 2): Hypopygium almost 2× as wide as long, widest in basal quarter, medially with very deep emargination. Epandrial claspers simple and long (length/width ratio ca. 5.8) and covered by long pale hairs, the longest hair up to 1.75 longer than width of epandrium. Apical stylus of gonostylus robust and rounded apically, secondary lobe long, reaching almost 0.75 of apical stylus length. Media lobe of basal lobe of gonostylus long and sharply pointed (saber-like); anterior lobe of basal lobe of gonostylus bulbous apically with several setae at extreme apex.

Figure 2. 

Ptychoptera xanthopleura sp. nov. terminalia a epandrium b paramere c aedeagal complex d gonostylus e hypandrium. Abbreviations: ECP = epandrial clasper, EL = epandrial lobe, EPI = epiproct, GBM = medial lobe of basal lobe of gonostylus, GAS = apical stylus of gonostylus, ALP = lateral ejaculatory process.

Female. The authors have an immature female which was sampled in Lesser Caucasus (Georgia, Kakheti region, Ilto river, above (N of) the Chart’ala village, 790 m a. s. l., 42°8'18"N, 45°7'32"E, 8.VII.2019, leg. P. Manko & G. Vinçon). The characters correspond to the above-described new species. However, its identity cannot be confirmed in this stage of ontogenesis/development and could be solved after collecting more specimens of the genus Ptychoptera from the Transcaucasia.

The name reflects predominantly yellow pleurae (Fig. 1b), which are unique for the Western Palaearctic species.

According to the presence of auxiliary sexual organ and shining pleurae, P. xanthopleura sp. nov. belongs to the subgenus Paraptychoptera and according to male genitalia and the maximum parsimonious tree based on 53 morphological characters (see Fig. 3 and Table 1), the nearest species is P. lacustris and belongs to the highly divergent monophyletic unit, the lacustris group, including five species, P. xanthopleura sp. nov., P. lacustris, P. castor, P. helena, and P. pollux (Fig. 3). Ptychoptera xanthopleura sp. nov. is close to but differs from the most similar species P. lacustris mainly by having an almost completely yellow pleurae, the shape of the hypopygium (epandrial claspers, secondary lobe of gonostylus, and medial lobe of basal lobe of gonostylus).

Figure 3. 

The maximum parsimonious tree based on 53 morphological characters. The characteristics are shown above branches. The parentheses show the maximum parsimony phylogeny bootstrap support value expressed as percentages. Support values under 40 are not shown.

Holotype : 1 ♂: Bulgaria, Rhodopes, Yundola, 1 300 m a. s. l., 42°3'47"N, 23°51'17"E, 30.VI.2016, leg. M. Barták et Š. Kubík.

Male. Head: Frons, vertex, and occiput black, mouthparts including palpi pale yellow, scape and pedicel yellowish orange, antennal flagellomeres greyish.

Thorax : Predominantly black with silvery pubescent pleurae. Pronotum, epimeron 3 and metanotum 3 yellow. Fore and mid coxae and trochanters yellow, hind coxae brownish black basally, yellow apically, coxae also yellow. Almost all legs are missing. Halteres whitish yellow with a darker knob.

Wing length 12 mm (Fig. 4b). Wing with yellowish veins and infuscated spots on fork vein Rs+R, all cross-veins, end of R₁ vein up to its fork with R₂ vein, on fork vein R₄+R₅ and on fork vein M₁+M₂. Legs: femur pale, darker in apical ¹⁄5, almost black on extreme apex; tibia pale brown in basal ½, darker apically and almost black on extreme apex; tarsomere 1 almost black, tarsomeres 2 and 3 dark brown, tarsomeres 4 and 5 pale brown.

Figure 4. 

Ptychoptera staryi sp. nov. a habitus of male, lateral view b wing.

Abdomen : Tergum 1, tergum 2, apical ¹⁄5 of tergum 3, almost whole tergum 4 except base, and whole terga 5–7 black; sternum 1 black, sternum 2 brown, sterna 5–7 black; the remainder orange yellow.

Male genitalia : similar to P. incognita. Epandrial clasper slightly curved outwards with simple obtuse apex; anterior projection of ventromesal lobe sharp, posterior projection bow-shaped backwards; space between both projections is rounded, almost semi-circular. Gonocoxite and gonostylus: apical process of paramere with a U-shaped dark structure with thick edges; paramere base rounded, convex; width to height ratio of dorsal gonocoxal lobe 0.5; dorsal gonocoxal lobe with dense tiny dark hairs. Aedeagus: sides of lateral ejaculatory process distinctly convex, basal projections markedly convergent; transition to lateral ejaculatory process smooth, undulate. Hypandrium: width to length ratio 1.2; apex of hypogynial valves start under basal division of hypandrium. See also differential diagnosis.

Female. Unknown.

The name is dedicated to our colleague Jaroslav Starý and his life jubilee. (Jaroslav discovered the holotype of new species in his own material and provided it for the description).

The new species is very similar to P. incognita Török, Kolcsár & Keresztes, 2015 (see also Table 2). After comparing the holotype of P. staryi sp. nov. with individuals of P. incognita (material used in Török et al. 2015: 2 individuals from Bulgaria, 17 individuals from Romania), we found that a diagnosis was possible on the basis of differences in male genitalia (Fig. 5, marked with arrows), namely: (i) shape of the plate on ventral parts of epandrium is of a different shape and orientated at a different angle in P. staryi; (ii) chitinisation (sclerotisation) of the proximo-lateral processes of the gonocoxite is not developed and these processes are light coloured in P. staryi in contrast to P. incognita with strong chitinisation and dark colouration; (iii) the hairs of margins of gonocoxite, gonostylus, and epandrium are much less dense and finer in contrast to P. incognita (not visible in Fig. 5).

Figure 5. 

Epandrium, gonocoxite and gonostylus, and hypandrium of P. staryi sp. nov., P. incognita, and P. albimana. Abbreviations: ECP = epandrial clasper, EL = epandrial lobe, EPI = epiproct, GBM = medial lobe of basal lobe of gonostylus, GCT = gonocoxite, GAS = apical stylus of gonostylus, GAT = tertiary lobe of apical stylus of gonostylus, PPA = apical process of paramere, HBD = basal division of hypandrium, HMW = membranous window of terminal division of hypandrium, HTD = terminal division of hypandrium.