Phthorarcha ishkovi Viidalepp, 1986

Kostjuk, Igor, Mironov, Vladimir G. & Viidalepp, Jaan, 2020, Review of the Central Asian species of Phthorarcha Meyrick (Geometridae Alsophilinae) with description of a new species, Zootaxa 4861 (2), pp. 232-240 : 237-238

Phthorarcha ishkovi Viidalepp, 1986 , comb.rev.

Phthorarcha ishkovi Viidalepp, 1986: 62 . TL: Kazakhstan, Western Tian Shan , Novonikolajevka. The Holotype is deposited in the ZISP collection, St. Petersburg, Russia.

Material. Holotype, male, Kazakhstan, Aksu–Dzhabagly NR, Novonikolajevka , at light, 4.IV 1978, Ishkov leg. ( ZISP) . Paratypes, 3♂, the same locality but 16–20.III 1979, Ishkov leg ; 4♂, [ Kazakhstan, Aksu–Dzhabagly NR] Dzhabagly vil., 1300 m, at light, 10.IV 1976, Ishkov leg. ( ZISP, IZBE (gen slides 2879, 2880), ZMKU and Aksu– Dzhabagly NR museum) .Additional material: 1♂, [ Kazakhstan] Alma–Ata, Glubokaya Stshel’, 14.IV 1936; 1♂, the same locality but 17.IV 1936, V. Shaidurov [leg.] ( ZISP); 1♂, Kazakhstan, Talasskiy Alatau Mts. , Novonikolajevka, 30.III 1975 , Ishkov leg. (Genit. pr. 445 I. Kostjuk), 1♀, [ Kazakhstan] Novonikolajevka , 5. IV 1979, at daylight lamp , Ishkov leg.(Genit. pr. 576 I. Kostjuk), 5♂, Kazakhstan, Dzhambulskaya region , road Bishkek—Alma–Ata, Kurday- skiy pass, 800 m, 21.04.1996, V . Lukhtanov leg. (Genit. pr. 446 I. Kostjuk), 5♂, Kyrgyzstan, Kirgizskiy Mts. , near vil. Sosnovka, N Tjuz–Ashoo pass, 1500 m, 22.04.1996, V . Lukhtanov leg., 3♂, Kyrgyzstan, road Bishkek—Osh at river Chichkan, 20 km N Toktogul, 1600 m, 23.04.1996, V . Lukhtanov leg. (Genit. pr. 325 I.Kostjuk) ( ZMKU) .

Diagnosis: Externally similar to P. primigena , wing markings a little darker, dark grey, and discal spots distinct on hindwings (hindwing discal spots inconspicuous in P. primigena ); light grey marginal vein-spots on hindwings absent. Hindwing distal margin evenly rounded at vein M3 as in P. primigena , not slightly angulate as in P. haber- haueri. Male antennae dentate with lateral tufts of long bristles ( Fig. 22 ). Male genitalia ( Fig. 18 ): Uncus triangular, as long as wide at base (much more slender in other species). Valva shorter and broader than in related species, and the two dorsal processes of the valva are of equal length.

Description. Male. Wingspan 30–33 mm ( Figs 7–11 ). Wing markings dark grey-brown on grey background, the scaling semi-transparent. Wing markings more contrasting than described for preceding species above. The medial field of forewing twice as broad at costa than at hind margin, the postmedial line straight and thinly dentate at veins, edged distally by a pale grey fascia. The forewing apical streak dark grey, broken at middle. Underside of wings grey, discal spots and a costal spot at the origin of the postmedial fascia dark grey. Hindwing whitish, discal spots and marginal vein-spots light grey. Male genitalia ( Fig. 16 ): Uncus and valva as diagnosed above, the latter distally rounded (angulate in other species). The juxta is long, slender and Y shaped. The aedeagus is strongly curved and deeply furrowed, the cornutus tapers distally, 0.8 mm long. Female ( Fig. 15 ) grey with slender legs and filiform antennae, wings not visible. Female genitalia ( Fig. 26 ): ostium oval, smaller than in P. primigena , ductus bursae also shorter, signum absent.

Distribution: Tian Shan Mts. in Kazakhstan and Kyrgyzstan. See Fig. 27 .

Figures

FIGURE 27. Distribution map of Middle Asian species of Phthorarcha Meyrick.

FIGURES 20–24. Male antennae. 20, P. primigena; 21, P. haberhaueri; 22, P. ishkovi; 23, Alsophiloides acroama; 24, Chimaphila zabolne

FIGURES 16–19. Male genitalia of some Phthorarcha species: 14, P. primigena, Lectotype, Prov. Samarkand (Gen. pr. 324); 15, P. haberhaueri, sp. n., Holotype, [Prov. Samarkand] (Gen. pr. 323); 16, P. ishkovi, Novonikolajevka (Gen. pr. 445); 17, P. chaoticaria, Holotype, “Nian Schian” (photo of gen.pr. from E. Beljaev)

FIGURES 1–15. Phthorarcha moths of Central Asia: 1–12, males, 13–15, females. 1, P. primigena, Lectotype, Prov. Samarkand; 2, P. primigena, Paralectotype, [Prov. Samarkand]; 3, P. primigena, Paralectotype, [Prov. Samarkand]; 4, Phthorarcha haberhaueri, sp. n., Holotype, [Prov. Samarkand]; 5, Phthorarcha haberhaueri, sp. n., Paratype, [Prov. Samarkand]; 6, Phthorarcha haberhaueri, sp. n., Paratype [Prov. Samarkand]; 7, P. ishkovi, Holotype, Novonikolajevka; 8, P. ishkovi, Paratype, Novonikolajevka; 9, P. ishkovi, Alma–Ata; 10, P. ishkovi, Chichkan; 11, P. ishkovi, Sosnovka; 12, P. chaoticaria, Holotype, Nian Schian; 13, P. primigena, Paralectotype, [Prov. Samarkand]; 14, P. primigena, Paralectotype, [Prov. Samarkand]; 15, P. ishkovi, Novonikolajevka. Scale bar 10 mm.

FIGURES 25–26. Female genitalia. 25, P. primigena, Paralectotype, [Prov. Samarkand] (Gen. pr. 577); 26, P. ishkovi, Novonikolajevka (Gen. pr. 576)