Cylindrotoma nigriventris Loew, 1849

Kolcsar, Levente-Peter, Paramonov, Nikolai, Imada, Yume, Kato, Daichi, Gamboa, Maribet, Shinoka, Dai, Kato, Makoto & Watanabe, Kozo, 2022, Notes on the taxonomic status and distribution of some Cylindrotomidae (Diptera, Tipuloidea), with emphasis on Japanese species, ZooKeys 1083, pp. 13-88 : 13

Cylindrotoma nigriventris Loew, 1849

Figs 9 , 10

Non-type material examined.

Finland • 1 ♂; Lohja, Karkola; 60.60841°N, 23.95901°E; alt. 125 m; 9 Jun. 2018; E. Viitanen leg.; CKLP. Russia • 1 ♂; Altai Republic, Ongudaysky District, Onguday, Seminsky Pass; 51.06°N, 85.59°E; alt. 1650 m; 27 Jun. 2016 - 30 Jun. 2016; N.E. Vikhrev leg.; CKLP. • 1 ♀; Altai Republic, Kupchegen Settlement, Chike-Taman Pass; 50.64477°N, 86.3117°E; alt. 1266 m; 28 Jun. 1964; E.P. Narchuk leg.; CKLP.

Supplementary description.

Male terminalia: Directed dorsally. Tergite 9 partly fused with gonocoxite (Fig. 9C ). Posterior margin of tergite 9 with deep, U-shaped notch (Fig. 9A ). Posterior edge of tergite 9 forming dorsal and ventral portion in lateral view (Fig. 9C ). Ventral part produced caudally, forming finger-like lobe, covered by long hairs; dorsal portion wavy, formed by posterior margin of tergite 9 (Fig. 9C ); lateral part of dorsal portion bent under tergite 9, forming a gently curved plate, covered with few fine setae, visible in caudal view. Gonocoxite fused with sternite 9 (Fig. 9B, C ); sternite 9 sclerotised with few long hairs. Gonocoxite ventral lobe, laterally flattened, directed dorso-laterally, shape as in Fig. 9D ; apical lobe of gonocoxite directed caudally, not inward as in C. distinctissima or C. americana ; covered by long hairs, except small bare portion at base, next to gonostylus, visible in ventral view (Fig. 9B ). Gonostylus undivided, twisted; base wide, with a small gently curved finger-like lobe directed inward; inner ventral part paler, slightly membranous; in caudal view medially with outgrowth ridge (Fig. 9E ); gonostylus narrowing to tip in caudal view. Interbase small, without membranous median part (Fig. 9F ). Aedeagus dorsoventrally flattened, gently curved dorsally (Fig. 9H ), tip divided into three short, equal tubes in last 1/4 of its length (Fig. 9F, G ). Spines on inner side of lateral branch of aedeagus large, distinct, forming spike-like outgrowth (Fig. 9I ); in lateral view individual spine can be separated (Fig. 9H ).

Female terminalia: (Fig. 10A ). Very similar to terminalia of C. distinctissima and C. americana stat. reval. The only clear difference is the sclerotisation of lateral sperm ducts (Fig. 10B ), corresponding to the position of large spines on lateral branches of aedeagus (Fig. 9I ). Spermathecae small (Fig. 10C ), diameter ~ 0.08-0.12 × width of sternite 8 (in inner dorsal view).

Distribution.

Palearctic species, distributed from Finland to Far East Russia. Reported from Finland, Kazakhstan, Mongolia, and Russia: North European Russia, West Siberia (Altai Republic), East Siberia (Irkutsk Oblast), Far East Russia (Sakhalin Oblast, Primorsky Krai) ( Oosterbroek 2021). The species was reported from the Altai Republic (Russia) by Soós and Oosterbroek (1992), but without any collection data, here we publish the first confirmatory record from the Altai Republic.

Comments.

Besides the apparent terminal differences in male specimens, the only distinct difference between C. nigriventries , C. distinctissima , and C. americana stat. reval. noted in our study, was the colouration of the scutellum, which is yellow in the latter two species, and with a median brown stripe or patch in C. nigriventries . Salmela and Autio (2007) and Gelhaus et al. (2007) note that these species also differ in the colouration of the abdomen (dark brown, almost black in C. nigriventries , and yellowish brown in C. distinctissima ), however, some of the Japanese species of C. distinctissima have a very dark brown abdomen (Fig. 3A ). The illustration of the female terminalia of C. nigriventris by Gelhaus et al. (2007: fig. 9) shows a high similarity to the drawing of the female terminalia of C. distinctissima by Peus (1952: fig. 21b), making the former suspect.

Figures

Figure 3. Cylindrotoma distinctissima (Meigen, 1818) A habitus of male, lateral view (colouration of wings is artefact) B thorax of male, lateral view C head and thorax dorsal view of pale " Cylindrotoma distinctissima " form D head and thorax dorsal view of dark, " Cylindrotoma japonica " form E head of female, lateral view F head of male, lateral view G female terminalia lateral view.

Figure 9. Male genital structures of Cylindrotoma nigriventris Loew, 1849 A terminalia, dorsal view B terminalia, ventral view (aedeagus complex removed) C terminalia, lateral view D ventral lobe of the gonocoxite, lateral view E shape of the gonostylus, caudal view F aedeagus complex, dorsal view G aedeagus complex, ventral view H aedeagus complex, lateral view I tip of the aedeagus.

Figure 10. Female genital structures of Cylindrotoma nigriventris Loew, 1849 A terminalia, lateral view B sperm ducts C Spermathecae.