Micropterix gaudiella Zeller & Huemer, sp. n. is described from the southern part of the Orobian Alps (Piedmont, Italy) and compared with its likely closest relatives Micropterix isobasella Staudinger, 1871 and Micropterix stuebneri Zeller, Werno & Kurz, 2013. The new species is well characterized by its wing pattern and colour and by structures of the male genitalia. The species status is furthermore supported by molecular data of the DNA barcode region. The distance to its nearest neighbour Micropterix schaefferi Heath, 1975 is 2.65%. M. gaudiella is the seventh species of the genus Micropterix Hübner, 1825 probably endemic to the Alps.

The European fauna of Micropterigidae has recently gained increasing attention, reflected by faunistic reviews and several taxonomic papers (Corley 2007; Zeller-Lukashort et al. 2007; Thierry and Nel 2012; Zeller-Lukashort et al. 2013). The actual species inventory now seems well advanced as new species are rarely found and usually originate from insufficiently explored Mediterranean countries, with only two remarkable exceptions from the Central European Alps within the last four decades (Heath and Kaltenbach 1984; Kurz et al. 2004). Sampling of an unidentified Micropterix in the Italian Alps (Pizzo Arero, Orobian Alps, Piedmont, Italy) by PH and colleagues in June and July 2013 and 2014 thus came as a surprise. Although only few females were available in first hand, phenotypic appearance and the DNA barcode did not match any hitherto described species from the region. It was therefore decided to search for additional samples and we finally succeeded in collecting a large series of the species in summer 2014 including the male sex. Subsequent analysis of male genitalic characters supported the recognition of a new species, which is described here.

Our study is based on almost 277 specimens of the new Micropterix species and uncounted material of all European congeners. The type material is only partially set whereas several samples were only spread and dried immediately after collecting to ensure sufficient quality of DNA samples. Genitalia preparations followed standard techniques used for the family Micropterigidae (Zeller-Lukashort et al. 2007). Photographs of the adults were taken with an Olympus SZX 10 binocular microscope and an Olympus E-3 digital camera and developed using the software HELICON FOCUS 4.3, ADOBE PHOTOSHOP CS4 and LIGHTROOM 2.3. DNA barcode sequences are based on a 658 base-pair long segment of the mitochondrial COI gene (cytochrome c oxidase 1). DNA samples (dried legs) were prepared according to the prescribed standards (deWaard et al. 2008). Present authors and associated colleagues tried to obtain DNA barcodes of the majority of European Micropterigidae. Legs from 379 specimens belonging to 57 species of Micropterix have so far been processed at the Canadian Centre for DNA Barcoding (CCDB, Biodiversity Institute of Ontario, University of Guelph) to obtain DNA barcodes (BOLD 2015) using the standard high-throughput protocol described in Ivanova et al. (2006) and deWaard et al. (2008). DNA sequencing resulted in a barcode fragment of 658 bp for a total of 149 specimens and 29 species (BOLD 2015), partially published earlier by Lees et al. (2010). Ninety-one sequences belonging to 25 species are treated in this study and enable delimitation of the new species. Details of successfully sequenced voucher specimens including complete voucher data and images can be accessed in the Barcode of Life Data Systems: public dataset “Lepidoptera of the Alps - Micropterix [DS-LEALMIC]” (BOLD 2015; Ratnasingham and Hebert 2007). Degrees of intra- and interspecific variation in the DNA barcode fragment were calculated under Kimura 2-parameter (K2P) model of nucleotide substitution using analytical tools in BOLD Systems v3.0 (BOLD 2015). A neighbour-joining tree of DNA barcode data of European taxa was constructed using MEGA 5 (Tamura et al. 2011) under the K2P model for nucleotide substitutions.

The morphology of the new species is compared with similar species from the Alps and also from other regions of Europe (Kurz and Kurz 2015). We consequently build on the important identification treatments by Heath (1987), Kozlov (1989, 1990a, b) and Zeller-Lukashort et al. (2007). For more information about collection sites, preparation techniques and data archive of Micropterix spp. see Zeller-Lukashort et al. (2007).

Abbreviations of private and institutional collections:

MBCG Italy, Bergamo, Museo di Scienze Naturali “Enrico Caffi”;

RCTM Research Collection Toni Mayr, Feldkirch, Austria;

RCCZ Research Collection Christof Zeller, Thalgau, Austria;

RCNP Research Collection Norbert Pöll, Bad Ischl, Austria;

RCSO Research Collection Siegfried Ortner, Bad Ischl, Austria;

TLMFTiroler Landesmuseum Ferdinandeum, Innsbruck, Austria.

Alpha-taxonomy of European Micropterix seems quite well established with relatively few taxa described during the last decades, so it is striking to find a new species in Central Europe. By contrast, the distribution of the majority of Micropterix species is only moderately well documented with few faunistic studies, particularly as concerns the Mediterranean region. Despite this shortcoming, it already appears evident from published sources that Micropterix exhibits remarkable levels of narrow range endemicity. Indeed about three-quarters of the European taxa can be clustered into the following disjunct endemism groups (Karsholt 2015; Zeller-Lukashort et al. 2013; Kurz and Kurz 2015).

Apennines: 9 out of 20 species are endemic.

Alps: 7 out of 19 species are endemic.

Balkan Peninsula: 9 out of 17 species are endemic.

Iberian Peninsula: 5 out of 8 species are endemic.

Mediterranean islands: 8 species are endemic.

Black Sea area: 1 species is endemic.

Also, only 12 species (about one-quarter of European Micropterix) are widely distributed across Europe, and only one species (M. aureatella) reaches Japan (Kurz and Kurz 2015). M. aruncella, M. aureatella, M. calthella, M. mansuetella and M. tunbergella are known to range across from the mainland to geographically well separated islands (although a few micropterigids occur within an island group, such as Sabatinca occurring in both North and South Island of New Zealand: Gibbs 1983; Gibbs and Lees 2014; see also Imada et al. 2011). Endemism in the Lepidoptera fauna of the Alps in general and Micropterix in particular probably largely results from the history of glaciation, which is reflected in nine biogeographic zones defined by vegetation (Ozenda 1988). These zones have been partially considered as areas of endemism for Lepidoptera (Huemer, 1988). The majority of endemic Micropterix occur in the Western Alps and are restricted to the so-called “Inner Alps” (i.e. M. isobasella, M. paykullella, M. trifasciella and M. fenestrellensis) whereas M. huemeri is restricted to the adjacent “Pre-Ligurian” biogeographic zone. However, the highest diversity of endemic Lepidoptera in general is present in the so-called “Gardesan-Illyrian zone” of the south-eastern Alps which is defined by limestone massifs at the southern border of the Alps reaching from Lake Como in the west to the Karawanks in the east. More than 30 endemic Lepidoptera species are known from this area (Huemer 1998). M. gaudiella is the first species of the genus Micropterix probably endemic to this zone, while a further species, M. rablensis, is more widespread and also occurs in the northern part of the Eastern Alps. The Orobian Alps in particular seem to have attracted insufficient attention among lepidopterists so far and still host a considerable number of cryptic species belonging to various groups. A new species of Kessleria (Huemer & Mutanen, 2015) and a distinct subspecies of Colostygia (Huemer & Mayr, 2015) are striking examples. It seems not unlikely that further undescribed endemic Micropterix may be found in other remote and undercollected areas of Europe, e.g. on the Balkan and Iberian Peninsulas. Outside Europe, despite the efforts of John Heath, there are probably a number of undetected species in North Africa, while the Himalayas as far as China are virtually unexplored for the genus (but see Lees et al. 2010).

We are particularly grateful to Paul Hebert and his team at the Canadian Centre for DNA Barcoding (Guelph, Canada), whose sequencing work was enabled by funding from the Government of Canada to Genome Canada through the Ontario Genomics Institute. We are also grateful to the Ontario Ministry of Research and Innovation and to NSERC for their support of the BOLD informatics platform. We are furthermore indebted to the Promotion of Educational Policies, University and Research Department of the Autonomous Province of Bolzano – South Tyrol for helping to fund the project “Genetic biodiversity archive – DNA barcoding of Lepidoptera of the central Alpine region (South, East and North Tyrol)”, and to the Austrian Federal Ministry of Science, Research and Economics for funds received in the framework of ABOL (Austrian Barcode of Life).

Dr. Marko Mutanen (Oulu) and Dr. Andreas Segerer (Munich) kindly gave us access to unpublished barcode sequences. We are furthermore grateful to Toni Mayr, Siegfried Ortner and Norbert Pöll for the loan of their material and provision of useful photos, to Mag. Michael Kurz for help regarding the preparation of the female genitalia. Dr. David Lees (London) and Martin Corley (Faringdon, Oxford) kindly improved our English and gave us useful hints. Stefan Heim (Tiroler Landesmuseen, Innsbruck) kindly developed figures of set adults and genitalia. Finally we acknowledge the kind support received from Dr. Marco Valle, Dr. Paolo Pantini and Dr. Melania Massaro (Museo Civico di Science Naturali “E. Caffi”, Bergamo) during our stay in Italy and supplementing samples of the new species.