Dichrorampha pentheriana (Rebel, 1917)

Zlatkov, Boyan, 2016, Taxonomy of two montane Dichrorampha species from the Balkans and Caucasus (Lepidoptera, Tortricidae), Nota Lepidopterologica 39 (1), pp. 13-20 : 14-16

Taxon classification Animalia Lepidoptera Tortricidae

Dichrorampha pentheriana (Rebel, 1917) Figs 1-4, 7-10, 14

Material.

2 ♂, Bulgaria, Vitosha Mts, near Cherni vrah chalet, 2100 m a.s.l., N 42°34 ’20’’ E 23°17 ’03’’, 11.vii.2015, leg. B. Zlatkov & E. Tasheva, coll. BFUS; 2 ♀, ibid.; 2 ♀, ibid. but 13.vii.2012, leg. B. Zlatkov & D. Gradinarov; 1 ♀, ibid. but 25.vii.2013, leg. B. Zlatkov.

Redescription based on the Bulgarian specimens

(Figs 2-4). Sexual dimorphism subtle. Head: Frons and vertex pale brown, palpus labialis yellow encircled with black scales. Antennae with beige scales. Thorax: Upperside, including patagia and tegulae, grey-brown, in some specimens scales with beige tips. Underside anterior pale grey, posterior and legs dark grey. Forewing length male 6.7-6.8 mm, female 5.7-6.5 mm, wingspan in set specimens 12.0-14.5 mm. Forewings moderately wide, without costal fold in males, with slightly convex costal edge (more convex in females than in males). Upperside wing pattern contrast, especially in females (Figs 3, 4), consisting of numerous pale and dark transverse lines. Nine pairs of creamy distinct costal strigulae. Lead refractive transversal lines (striae) emerge from pairs 3-7; line of pair 3 ill-defined and pronounced only in some specimens; line of pair 4 reaching the discal cell; lines of pairs 5 and 6 initially merged then divided forming the refractive lines of the speculum; line of pair 7 short, dot-like; lines of pairs 8 and 9 relatively short, convergent and connected with creamy terminal ( “postapical”) strigulae. All pattern elements from the wing base to the median fascia consist of black and beige ill-defined lines, forming a vestigial dorsal patch in the region of the interfascial area basad to the median fascia. Median fascia darker, with black and golden-tipped scales; these scales predominate in the distal wing pattern. Four black terminal dots are present in most specimens; in some an additional dot above the terminal strigula is present. Forewing underside beige-grey, with distinct costal and terminal strigulae and terminal dots corresponding to the same upperside elements. Cilia grey-brown with pale median line. Hindwings upperside monochrome grey-brown with beige terminal line. Underside pale grey with paler terminal line. Cilia paler than those of the forewing. Abdomen dark grey.

Male genitalia (Figs 7-9): In agreement with the preparation of the genitalia of the lectotype as well as the description by Razowski (1971). The shape of valva and phallus depends on the pressure of the coverslip. For example, the cavity at the proximal part of cucullus looks deeper or shallower depending on the pressure applied. The same is valid for the phallus: the large triangular terminal process in natural condition is pointed laterally at right (Figs 8, 9), but under a coverslip it is ventrally oriented (Fig. 7).

Female genitalia (Fig. 10): In agreement with the preparation of the genitalia of the female paralectotype and the description by Razowski (1971).

Diagnosis.

The wing pattern of Dichrorampha pentheriana resembles that of Dichrorampha distinctana ( Herrich-Schäffer, 1851) but is easily distinguished by lacking the costal fold. The male genitalia are distinctive and do not show obvious affinities to other species of the genus. The shape of the valva is relatively similar to those of some forms of Dichrorampha plumbana (Scopoli, 1763), but the phallus is strikingly different. The female genitalia are less characteristic, with antrum (sclerotised posterior part of ductus bursae) similar to some extent to those of Dichrorampha bugnionana (Duponchel, 1843).

Biology.

The species is on the wing from mid June to late July. The larval host plant in all likelihood is Achillea lingulata Waldst. & Kit., considering the fact that many Dichrorampha feed on Achillea and all specimens were swept during the florescence period of Achillea lingulata from its stems or surrounding grass vegetation. Other Achillea spp. and also other Asteraceae growing in the vicinity were searched for Dichrorampha pentheriana without a positive result, so Dichrorampha pentheriana is likely to be monophagous. The habitat is a subalpine meadow at an altitude of ca. 2000 m (Fig. 14).

Distribution.

Zljeb Massif (part of Prokletije Mts, between Montenegro and Serbia) and Vitosha Mts (Bulgaria).

Remarks.

Rebel (1917) described Dichrorampha pentheriana from three specimens (2 males, 1 female) collected in Zljeb Mountains, Montenegro, at an elevation of 1700 m, preserved in NHMW. Obraztsov (1953) did not examine the type series and erroneously claimed that it consists of only two males. Danilevsky and Kuznetzov (1968) also did not examine the specimens and similarly gave wrong information about the specimens of the type series: three males and one female. Razowski (1971) dissected a male and female syntype, designated the male as lectotype, and provided descriptions and illustrations of male and female genitalia for the first time. The subtle differences in the genitalia of the Bulgarian specimens compared to those of the type series are likely due to normal variation and/or deformation by pressure of the coverslip.

No colour illustrations of the adult can be found in literature with the exception of those in Razowski (2003) (paralectotype male; the photograph is apparently altered digitally and shows some differences with the original appearance of the specimen). The lectotype (Fig. 1) is illustrated here for comparison with some of the Bulgarian specimens. As seen in the figure, the moths from Vitosha demonstrate two differences with the types: a more contrasting forewing pattern, especially in females and the presence of pale terminal line on the hindwings.