Dahlica (Brevantennia) triglavensis (Rebel, 1919)

Rekelj, Jurij, Predovnik, Zeljko, Huemer, Peter & Lopez-Vaamonde, Carlos, 2022, Systematics of Slovenian Dahlica Enderlein, 1912, subgenus Brevantennia Sieder, 1953 (Lepidoptera, Psychidae), Nota Lepidopterologica 45, pp. 207-232 : 207

Dahlica (Brevantennia) triglavensis (Rebel, 1919)

Figs 6 a-c , 7 , 8c, d , 9 , 10 , 11

Solenobia triglavensis Rebel, 1919: 111.

References for Slovenia.

Rebel 1919: 110; Kusdas 1944: 247; Sieder 1953: 120; Meier 1955; Sieder 1956 b: 225; Forster and Wohlfahrt 1960: 201; Sieder 1972: 297; Carnelutti 1978, Carnelutti 1992: 79; Sauter and Hättenschwiler 1996: 40; Weidlich 1996: 166; Verovnik 2003: 444 [ »Julijci«]; Lesar and Govedič 2010: 49; Sobczyk 2011: 78; Arnscheid and Weidlich 2017: 71.

Material examined.

Paratype. Slovenia • 1♂; Julijske Alpe , Triglav; 2400 m; 17.vii.1912; leg. R. Spitz; coll. NHMW [Hauptsammlung - Psychidae ] .

Other material.

Slovenia • 3♂♂; Julijske Alpe , Kanin, Podi; 2250 m; 19-20.vii.2009; leg. J. Rekelj ; DNA barcode sample: 1♂ TIPSY164-12); coll. PCJR • 6♂♂, 13♀♀, with larval cases; same locality; 26.vi.2010 (e.p. 26-28.vi.2010); leg. J. Rekelj ; DNA barcode sample: 1♂ TIPSY162-12; coll. PCJR • 9♂♂, 7♀♀, with larval cases; same locality; 26.6.2010 (e.p. 26.6- 4.7.2010); leg. Ž. Predovnik ; DNA barcode sample: 1♂ TIPSY293-12; genit. prep. №:356, 329, T. Sobczyk; coll. PCŽP • 7♂♂; same locality; 16-18.vi.2012; leg. J. Rekelj ; 5♂♂ genit. prep. №: 204-207, 297, 299; coll. PCJR • 59♂♂, 35♀♀, with larval cases; same locality; 16-18.iv.2012 (e.p. 23-25.iv.2012); leg. J. Rekelj ; 1♂ genit. prep. №: 208; coll. PCJR • 14♂♂; same locality; 10-11.iv.2017; leg. J. Rekelj ; 1♂ genit. prep. №: 208; coll. PCJR • 3♂♂; with larval cases; same locality; 10-11.iv.2017 (e.p. 15-20.iv.2017); leg. J. Rekelj ; coll. PCJR • 6 ♂♂, 4 ♀♀, with larval cases; Julijske Alpe , Mangart; 2050 m; 26.vi.2016 (e.p. 1-3.vii.2016); leg. J. Rekelj ; 5♂♂ genit. prep. №: 244-248, Rekelj; coll. PCJR • 19♂♂, 12♀♀, with larval cases; Mojstrana - Belca ; 900 m; 15.4.2004 (e.p. 18-25.iv.2004); leg. M. Lasan ; coll. PCML • Several old larval cases; Karavanke , Belca, Jurčkov vrh; 840-907 m; 25.ix.2009, leg. Ž. Predovnik ; coll. PCŽP • 7♂♂, 10♀♀, with larval cases; same locality; 28.iii.2010 (e.p. 4-9.iv.2010); leg. Ž. Predovnik ; DNA barcode sample: 1♂ TIPSY294-12, 1♂ TIPSY295-12, 1♂ TIPSY296-12; coll. PCŽP • 21♂♂, 18♀♀, with larval cases; same locality; 25.iii.2011 (e.p. 8.iv.2011); leg J. Rekelj; DNA barcode sample : 1♂ TIPSY156-12, 1♂ TIPSY157-12, 1♂ TIPSY158-12, 1♂ TIPSY159-12; coll. PCJR • 8♂♂, 8♀♀, with larval cases; same locality; 24.iii.2012 (e.p. 25-30.iii.2012), leg J. Rekelj; coll. PCJR • 21♂♂, 10♀♀, with larval cases; same locality; 21.iv.2013 (e.p. 22-25.iv.2013), leg J. Rekelj ; 5♂♂ genit. prep. №: 219-223, Rekelj; coll. PCJR • 3♂♂; Karavanke , Stol; 2140 m; 22.vi.2014, leg J. Rekelj ; 1♂ genit. prep. №:124, Rekelj; coll. PCJR • 9♂♂, 6♀♀, with larval cases; same locality; 22.vi.2014 (e.p. 22-25.vi.2014); leg J. Rekelj; DNA barcode sample : 1♂ TIPSY748-15; 5♂♂ genit. prep. №: 209-213, Rekelj; coll. PCJR • 5♂♂; 21.vi.2014, same locality; leg. Ž. Predovnik ; coll. PCŽP • 19♂♂, 1♀, with larval cases; same locality; 21.vi.2014 (e.p. 21-22.vi.2014); leg. Ž. Predovnik ; coll. PCŽP • 10♂♂, 2♀♀, with larval cases, same locality; 4.vi.2017 (e.p. 5-14.vi.2017); leg J. Rekelj; coll. PCJR .

Distribution.

D. triglavensis is distributed westwards to the Carnian Alps of Austria and Italy ( Sobczyk 2011, Arnscheid and Weidlich 2017). In Slovenia, the species is restricted to alpine areas in Julijske Alpe, and Karavanke. All localities are illustrated in Fig. 11 .

Biology.

D. triglavensis is a characteristic montane-alpine species. It is restricted to rocky habitats where the subsoil consists of limestone at an elevation from 800-2500 m. Observations in the natural habitat were carried out particularly on Mt. Kanin (Fig. 6c ), where we found them in the southern and south-eastern facing rocky slopes at an elevation from 2000-2300 m. The species inhabits slightly elevated areas of slopes that are sparsely covered with alpine vegetation such as Dryas octopetala L., Potentilla nitida L. and Carex sp. In the early spring, those areas become snow-free and later obtain less moisture and quickly heat up. The larval cases were fixed to the underside of small stones or gravel, individually also on the sides of the stones, or in cracks. D. triglavensis uses a mixed voltinism strategy (see below) which helps populations to persist in high alpine areas where the weather can be poor towards the end of the season. We found on the same stone old empty larval cases from previous years and new fresh cases with pupae from the current season as well as young larvae of different sizes. This behaviour at this elevation indicates that the species is semivoltine, likely with a two-year cycle ( Sieder 1953: 122).

Adults emerge from the beginning of June to mid-July, about three weeks after snow melt. They are active in the morning, when the habitat is illuminated by the first sunlight. D. triglavensis in Kanin locality cohabits with the following species of bagworms: Dahlica klimeschi (Sieder, 1953); Dahlica (Siederia) meierella ; Proutia raiblensis (Mann, 1870) and Leptopterix hirsutella (Denis & Schiffermüller, 1775).

On the Karavanke mountains we found this species on two localities at very different elevations. The first locality Jurčkov vrh, Belca lies on the south-eastern steep, rocky slope of entry Belca creek in a Genisto januensis - Pinetum zonal forest community, from 840-907 m. The vegetation is dominated by Pinus sylvestris L., Fraxinus ornus L., and Ostrya carpinifolia Scop. The larval cases were found on the underside of stones or gravel, also on the low areas of larger rocks or cliffs. The larvae are quite hidden throughout the season and feed on mosses, decomposing plants and lichens. At this elevation the species is univoltine. This behaviour has already been observed for D. triglavensis by Sieder (1953: 122). Larvae begin pupation in mid March to early April. The flight period of adults is in April and depends on the duration of the winter and the amount of snow cover.

At the Jurčkov vrh locality, D. triglavensis cohabits with the following bagworms: Dahlica triquetrella f. parth; Dahlica (Siederia) meierella ; Taleporia tubulosa ; Typhonia sp.; Psyche casta; Bijugis bombycella (Denis & Schiffermüller, 1775); Rebelia sp.; Canephora hirsuta (Poda, 1761); Leptopterix plumistrella ( Hübner, 1793); Megalophanes viciella (Denis & Schiffermüller, 1775) and Sterrhopterix sp.

The second Karavanke locality lies on the rocky slope of eastern ridge of Mt. Stol, just below the summit at an elevation of 2140 m in the alpine zone. The subsoil consists of limestone. The larval cases were found there in a microhabitat where rocks are in contact with soil, on the underside of stones or gravel and on the lower parts of larger rocks. Among the collected larval cases were also found a few active young larvae which indicate that the species is semivoltine, likely with a two-year cycle. At this locality we observed activity of adults as early as the end of June.

In Stol this species cohabits with the following species of bagworms: Dahlica goltella Rekelj & Predovnik, 2014; Dahlica klimeschi (Sieder, 1953); Proutia raiblensis and Epichnopterix ardua Mann, 1867.

Remarks.

Subendemic, type species of the subgenus Dahlica Brevantennia (Sieder, 1953: 120), with type locality in Slovenia: Julijske Alpe, Triglav, 2400 m ( Rebel 1919: 111).

Our DNA barcoding study revealed two distinct genetic lineages within the D. triglavensis group, representing different BINs (Suppl. material 1: Table S1). The first lineage consists of specimens from Julijske Alpe (BOLD:ABU8640), and a second one from Karavanke mountains (BOLD:ABU8641). Morphologically, these lineages are remarkably similar and despite precise studies of adults and immature stages of many specimens, no tangible morphological differences could be found that would exceed the normal range of variation of each population.

However, the morphology-based taxonomy and the distribution boundaries of these groups remain poorly defined, so we have decided to keep the same name for both populations.

Figures

Figure 6. D. triglavensis. a. Adult male resting on rock, Kanin; b. Female on the larval case in attracting mode, Kanin; c. Rocky slope with alpine vegetation, natural habitat of D. triglavensis, Kanin, 2250 m.

Figure 7. Graphical representation of genital indexes on different localities of D. triglavensis.

Figure 8. Heads, colouration of vertex and frons dense hairs. a. D. santicensis, Gozd Martuljek; b. D. santicensis, Retje, Ribnica; c. D. triglavensis, Jurckov vrh, Belca; d. D. triglavensis, Kanin; e. D. adriatica, Potok Mrzlek; f. D. styriaca, Haeuslberg bei Leoben.

Figure 9. Graphical representation of genital indexes and classes of cloaking scales of all species in subgenus Dahlica Brevantennia (after Arnscheid and Weidlich 2017, enriched by our own investigations).

Figure 10. Comparison of patterns and cloaking scales of male forewings: Slovenian and surrounding subgenus Dahlica Brevantennia species.

Figure 11. Distribution map of subgenus Dahlica Brevantennia species in Slovenia. 1. Prelovce, Vremscica; 2. Potok Mrzlek, Ribnica; 3. Zlebovi, Koritnice; 4. Devin, Zupnica; 5. Slavnik; 6. Mislice, Brkini; 7. Pregarje, Huje; 8. Obrov, Brkini (Weidlich 2012); 9. Gozd Martuljek; 10. Ratece, Gorenjska; 11. Mala Mojstrovka; 12. Mlinarica, Zg. Trenta; 13. Strmec na Predelu; 14. Kladje, Cerkno; 15. Zgornja Sorica; 16. Gradisce, Naklo; 17. Crnivec pod Plesivcem; 18. Strmec, Raduha; 19. Cezlak, Oplotnica; 20. Tolsti vrh, Mislinja; 21. Paski Kozjak; 22. Mrzlo Polje, Gracnica; 23. Lanise, Hrusica; 24. Nanos; 25. Kurescek, Zelimlje; 26. Mala Slevica, Velike Lasce; 27. Ravni vrh, Sodrazica; 28. Retje, Ribnica; 29. Breg pri Ribnici na Dolenjskem; 30. Trava, Podplanina; 31. Triglav, Julijske Alpe; 32. Kanin, Julijske Alpe; 33. Mangart, Julijske Alpe; 34. Stol, Karavanke; 35. Belca, Karavanke.