Minoa lutea Schwingenschuss, 1954 bona sp.

Minoa murinata form/ssp? lutea Schwingenschuss, 1954: Zeitschrift der Wiener entomologischen Gesellschaft 39 (6): 219 (Ukraine: Crimea; Caucasus: Tuapse). Syntypes, 2 ♀, most possibly lost (not existing in the Schwingenschuss collection, which is deposited in Museum Niederösterreich, St. Pölten). Regarded as a synonym of the subspecies M. murinata monochroaria by Hausmann & Viidalepp (2012). Herewith we upgrade this taxon from synonymy to species level and regard it as a bona species (see below).

Diagnosis (characters of M. lutea are given in parenthesis).

Minoa lutea with wingspan 17-23 mm, forewing 11-15 mm (wingspan 16-22 mm, forewing 10-14 mm in M. murinata).

Minoa lutea with unicolorous light yellow wings in both sexes with low variation; underside of the forewings suffused with some grey scales (in M. murinata wings unicolorous, usually mouse grey with brown hue, variable from pale grey to dark grey, sometimes warm pale brown; underside of the wings like upperside; even the slightly lighter specimens from western Balkan Peninsula don’t have the same deep yellow coloration of the specimens from Caucasus, Transcaucasus and eastern Turkey) (see figs 3 ─13). In both species fringes concolorous, discal spots absent.

Clear-cut diagnostic characters could be found on the asymmetrical genitalia capsule and are strongly correlated with differences in the cornuti. Minoa lutea has a genitalia capsule with elongated sacculus; cornuti consist of a short main cornutus and 0 to 3 tiny cornuti (M. murinata has a genitalia capsule with short sacculus; cornuti consist of single cornutus dagger-shaped and long, about half size of aedeagus) (see figs 14 ─21). In female genitalia, no diagnostic character was found between both species (see figs. 22 ─25).

DNA barcoding. There is a low mean genetic distance (0.8%) between the specimens of M. lutea (from northeast Turkey, Georgia and Russia) and specimens of M. murinata (from different European countries, including Spain). Minimum pairwise distance (BOLD aligner, pairwise distance model in BOLD gap analysis) is just 0.32% between both taxa, corresponding to two base pairs (see also fig. 2). In tree reconstructions, the COI haplotypes of M. lutea falls into the strongly variable haplotype pattern of M. murinata showing maximum pairwise distances of 3.45%. However, constant diagnostic characters on wings as described above, as well as on the male genitalia strongly support the treatment of the populations in Turkey, Transcaucasus and Caucasus as bona species. Similar cases of morphologically well-defined species which are BIN-sharing or even exactly haplotype-sharing are mentioned e.g. in Hausmann et al. (2013) or Müller et al. (2019). Such cases usually occur at a rate of 1-3% of regional faunas as shown in several studies (e.g. Hebert et al. 2010; Hausmann et al. 2013; Huemer & Hebert 2016; Hausmann et al. 2020).

Bionomy. Larval stages and foodplants needs to be studied. In north-eastern Turkey, habitats are bushy, sunny and stony slopes along valleys in mountain areas at an altitude of about 1600 m. In Altai Mountains (Russia) habitats are wind-protected sites on meadows with species-rich vegetation and single trees or scrubs at an altitude of 1000- 1800 m. The species were rare in all habitats and only very few specimen could be found after extensive search.

Behaviour. Diurnal activity. After disturbance, the individuals escape quickly (much faster than M. murinata), and they fly several meters high, over the tall shrubs. Thus, it is more difficult to catch them by a net (compared to M. murinata).

Distribution. M. lutea is a pontic species, recorded in eastern Turkey, Crimea, Caucasus and Transcaucasia. Most probably this species is distributed also in north-western Iran. The populations in central and southern Russia (see Beljaev & Mironov 2019) and Central Asia need to be re-examined based on male genitalia structure. Two examined populations from the Altai belong to M. lutea (see figs 11, 20─21 & 24).