Stigmella mespilicola Klimesch 1948

Stigmella mespilicola (Frey, 1856) Figs 9, 10, 28, 29, 31, 42, 43, 46, 47–51, 52 Nepticula mespilicola Frey, 1856: 392. Holotype ♂ Switzerland, Zürich, Uetliberg (ca. 47.35°N, 8.49°E), mines on Amelanchier, emerged 1856, Frey collection, Genitalia slide BM 21825 (NHMUK. Illustrated in watercolour by R. Johansson in Johansson and Nielsen (1990) and van Nieukerken et al. (2016). Nepticula ariella Herrich-Schäffer, 1860: 60. Syntypes Germany: [Regensburg], “ Raupe im Herbste in den Blättern von Sorbus aria ”. Depository unknown, types probably lost. Synonymised by Frey (1880: 422) under the name “ Ariae H. - S. ”. [colour plate published later, Herrich-Schäffer (1861: 32, f. 168)]. Stigmella ariella (Herrich-Schäffer, 1860) Klimesch 1948: 57, new combination, male genitalia. [Stigmella mespilicola (Frey, 1856) Klimesch 1948: 57, new combination. Misidentification for S. hybnerella (Hübner, 1796)]. Stigmella cotoneastri sensu Klimesch, 1948: 60. Stigmella mespilicola; important citations: Johansson and Nielsen 1990; Laštůvka and Laštůvka 1997; Robrecht et al. 2024. Recognition. Adult (Figs 9, 10, 51). Forewing length ♂ 1.7–2.2 mm (2.0 ± 0.2, n = 6), ♀ 2.3 mm (n = 2), wingspan ♂ 3.9–4.8 mm (n = 6), ♀ 5.0–5.3 (n = 2); antennae ♂ with 23–29 articles (26.7 ± 2.3, n = 6), ♀ with 22–24 (n = 2). Stigmella mespilicola is most similar to S. hybnerella (Hübner, 1796), but differs by darker, strongly shining copper brown forewing, purple along costa and black head in all specimens. Several S. hybnerella specimens, especially females, have a brown or yellowish hair tuft. In doubt genitalia should be examined. From S. torminalis it differs by the narrower, more distal and silver fascia and in the male by the presence of black androconial scales on the hindwing. Male genitalia (Figs 42, 43). Very different from most Stigmella species, except S. hybnerella, see figures. In comparison with S. hybnerella (Fig. 44), the valvae are shorter and do not reach the tip of the uncus in ventral view (they do reach that tip in S. hybnerella), the phallus is somewhat shorter, without the 3–4 large cornuti at the apex. Female genitalia (Fig. 46). As those of S. hybnerella with a strongly coiled accessory sac, with about four convolutions (6–7 in S. hybnerella, Fig. 45). Leafmines (Figs 28, 29, 31, 47–50). Egg more often on leaf upperside than underside, in ca 100 mines 28 % was on underside, but for mines in Torminalis this percentage is 40 % (n = 73); usually not on or near a vein, but upperside eggs may be sometimes deposited on top of a vein. Mine starts as an often rather contorted gallery, sometimes later following a vein for a short stretch, black frass line rather wide, in early mine often about half mine width in middle; frass often broken in several places, often distinctly zigzagging, in later mine usually not more than 1 / 3 mine width. Some mines have frass as narrow as in S. torminalis, but then more broken and less continuous. Margins of mine irregular, often bulged. Larva: pale whitish yellow, prothoracic sclerite pale brown to almost invisible, paired brains pale brown and well visible, larva with dorsum upwards. Cocoon: dark brown. Distribution (Fig. 52). Albania (new record, https://observation.org/observation/291620627/), Austria, Belgium (Wullaert 2017), Bosnia (new record), Bulgaria (new record), Croatia, Czechia, France (van Nieukerken et al. 2006) (new for departments 05, 06, 21, 31, 53, 55, 72), Germany (new for Niedersachsen, https://observation.org/observation/296867262/), Hungary, Italy, Luxemburg (new record, https://observation.org/observation/325644295/), Serbia, Slovakia, Slovenia (Maček 1999), Spain (van Nieukerken et al. 2004), Switzerland, Turkey (Klimesch 1978) and United Kingdom (England) (Emmet 1988; Agassiz 1992) (general references for distribution (Johansson and Nielsen 1990; Laštůvka and Laštůvka 1997; van Nieukerken 2018). Hostplants. Reared from Amelanchier ovalis, Aria edulis, Cormus domestica (L.) Spach (= Sorbus domestica), Cotoneaster integerrimus Medik., and Torminalis glaberrima. Records from Crataegus are certainly wrong (e. g. by Hering 1957; Maček 1999). Leafmines on Cotoneaster racemiflorus (Desf.) K. Koch (Klimesch 1978), Hedlundia mougeotii (Soy. - Will. & Godr.) Sennikov & Kurtto, Karpatiosorbus degenii (Ellis 2024), K. latifolia (Lam.) Sennikov & Kurtto and K. semiincisa (Borbás) Sennikov & Kurtto (the last four published as species in Sorbus) probably also belong to S. mespilicola. Szőcs (1981 b) recorded Sorbus aucuparia as host of Stigmella torminalis (specimen and leafmine cited below from Rupphegy). This represents a double misidentification, the reared moth being S. mespilicola and the host Cormus domestica. Another herbarium sample (Harshegy, 19. vii. 1958) was similarly identified, but no reared adult was available. Although the mine could belong to S. mespilicola, the identity of the host is uncertain, as Sorbus aucuparia is very rare to almost absent in Hungary (Räty et al. 2016), and leaves cannot be reliably separated from C. domestica. Life history. Bivoltine. Larvae are found from early June to July and from late August to October. Adults emerged respectively from late June to July, and from March to May. DNA barcoding (Fig. 53). We have ten DNA barcodes, seven from our own projects, three from the “ Lepidoptera of the Alps ” projects, eight of which have all BIN BOLD: ABW 6508, and two incomplete barcodes. The Maximum distance between these is 2.16 %, the average distance 1.29 %, nearest neighbour is the not closely related Stigmella fasciata van Nieukerken & Johansson, 2003, at a distance of 4.9 %. Remarks. On the basis of the genitalia figures in Klimesch (1948), the species feeding on Amelanchier was considered to be S. hybnerella, with exceptions (van Nieukerken 1986). Also a male reared from Amelanchier by Axel Scholz (collection Stuttgart) proved to be a S. hybnerella, but the holotype of S. mespilicola was also reared from Amelanchier. Apparently both species feed on Amelanchier, and we have no indication whether one of these is commoner than the other one. Rearing larvae or obtaining DNA barcodes is necessary to obtain a better idea of the distribution of both species on this host. Probably the mines of S. hybnerella on Amelanchier are more a linear-blotch type mine, and those of mespilicola linear, as on other hosts, but we have seen insufficient mines with a certain identification. Many records of this species on Torminalis were originally misidentified as Stigmella torminalis, see discussion above. Otherwise most literature references are reliable, with the exception of records on Aria (and hybrids) in the north of the British Isles (e. g. on GBIF) and Scandinavia, where S. magdalenae is often found feeding on these. The record from Turkey by Klimesch (1978) is also uncertain, as it is based on a single record of vacated mines on Cotoneaster Medik. and a female reared from Amelanchier, of which the genitalia have not been checked, and which could also belong to S. hybnerella. In fact the illustrated leafmines on Amelanchier (Klimesch 1978: figs 3 a, 3 b), linear-blotch mines, resemble more those of S. hybnerella, whereas that on Cotoneaster (Fig. 4) could well be a S. mespilicola mine. Material examined. Specimens cited from France and Spain earlier by van Nieukerken et al. (2004, 2006) are not repeated. Adults. – FRANCE • 1 ♂ 1 ♀; Alpes de Hautes-Provence, Digne; [44.09°N, 6.23°E]; 10 Sep. 1967; J. Klimesch leg.; Host: Cormus domestica; emerged 17 Mar. – 01 Apr. 1968; EventId: Zucht No. 931; ZSM .. – GERMANY • 2 ♀; Baden-Württemberg, Bad Ditzenbach, Leimbg., Kreuzkp. [Leimberg, Kreuzkapelle]; [48.584°N, 9.673°E]; alt. 700 m; 09 Sep. 1989; A. Scholz leg.; Host: Aria edulis; SMNS. • 2 ♂; Baden-Württemberg, Affalterbach, “ Lemberg ”; [48.82°N, 9.14°E]; alt. 360 m; 19 Sep. 1995; A. Scholz leg.; Host: Torminalis glaberrima; SMNS. • 1 ♂ 1 ♀; Baden-Württemberg, Urach Umg., Hohenwittlingen; [48.47°N, 9.423°E]; 01 Sep. 1989; A. Scholz leg.; Host: Cotoneaster integerrimus; SMNS. Genitalia slide: EvN 5468 ♀; DNA extract RMNH.INS.25468; SMNS. • 1 ♂; Baden-Württemberg, Lemberg Zuffh.; [48.82°N, 9.14°E]; [20 Sep. 1936]; A. Wörz leg.; Host: T. glaberrima; emerged 07 Mar. 1937; Genitalia slide: SMNS 3452; SMNS. • 1 ♀; same locality data; [05 Jun. 1937]; A. Wörz leg.; Host: T. glaberrima; emerged 22 Jun. 1937; SMNS [both identified and published by Wörz as Nepticula torminalis]. • 1 ♂; Baden-Württemberg, Lemberg-Horn; [48.817°N, 9.131°E]; A. Wörz leg.; Host: T. glaberrima; emerged 13 Jul. 1944; Genitalia slide: on pin; SMNS [identified and published by Wörz as Nepticula torminalis]. • 1 ♀; Thüringen, Bad Blankenburg; [50.68°N, 11.27°E]; H. Steuer leg.; Host: T. glaberrima; emerged 13 Jun. 1969; Genitalia slide: EvN 3145; Steuer collection, MfN [as Stigmella torminalis in Steuer 1984, corrected by Steuer 1991]. – HUNGARY • 1 ♂ 1 ♀; Budapest, Normafa; 47.504°N, 18.965°E; 09 Jun. 1973; J. Szőcs leg.; Host: T. glaberrima; emerged 02–03 Jul. 1973; EventId: Zucht: 79 / 73; Genitalia slides: VU 1755, VU 1756; HNHM [as Nepticula torminalis in Szőcs 1981 a] .. – ITALY • 1 ♂; Cuneo, Entracque-S. Giacomo, Vallone della Barra: Gias della Siula; [44.146°N, 7.376°E]; alt. 1600 m; 25 Jul. 2000; G. Baldizzone leg.; Genitalia slide: EvN 3359; Baldizzone, G., personal collection. • 1 ♂; Savona, Conna; [43.98°N, 8.11°E]; E. Jäckh leg.; emerged 04 May 1970; Genitalia slide: RJ 1134; ZMUC. • 1 ♂ (Fig. 9) 1 ♀; Savona, Noli; [44.21°N, 8.41°E]; 20 Sep. 1952; J. Klimesch leg.; Host: Cormus domestica; emerged 10–27 Mar. 1953; Genitalia slide: EvN 4240; DNA extract RMNH.INS.24240; ZSM. – SWITZERLAND • 1 ♀; Zürich, Zürich, [Uetliberg]; [47.351°N, 8.491°E]; Frey leg.; Host: A. edulis; Genitalia slide: BM 21826; NHMUK. – UNITED KINGDOM • 1 ♀; England, Lord’s Wood; [51.83°N, 2.65°W]; A. N. B. Simpson leg.; Host: T. glaberrima; emerged 1984; Genitalia slide: BM 24099; NHMUK. Leafmines and larvae. – AUSTRIA