Caryocolum arenariella (Benander, 1937)

Huemer, Peter, 2020, Integrative revision of the Caryocolum schleichi species group - a striking example of a temporally changing species concept (Lepidoptera, Gelechiidae), Alpine Entomology 4, pp. 39-63 : 39

Caryocolum arenariella (Benander, 1937)

Lita arenariella Benander 1937: 31, figs A, B. Syntypes, Sweden: Scania: Saltvik; Kivik; Borgeby, moths bred end of vii.1922 (larvae in Dianthus arenarius stems), leg. Benander [not traced].

Material examined.

Sweden: 3 ♂♂, 2 ♀♀, Sk., Tyngsjö, 4 Sep. l957, 24 Jul. 1965, leg. Svensson (ZCLU; NHM); 1 ♂, Sk., Vitemölla, 22-31 Jul. 1965, leg. Svensson ( ZMUC); 1 ♂, same data, but 8 Jul. 1988 e.l. ( Dianthus arenarius ); 3 ♂♂, same data, but 11 Jul. 1988 e.l.; 2 ♂♂, 1 ♀, same data, but 12 Aug. 1988 e.l., gen. slide GEL 1292 ♀ P. Huemer; 1 ♂, same data, but 17 Jul. 1988 e.l. (all TLMF); 1 ♂, [Schonen,] Kivik, 20 Jun. 1964, leg. Benander ( ZMUC). Latvija: 1 ♂, Mangalsala, 9 Aug. l977, leg. Sulcs ( ZMUC). North Macedonia: 2 ♂♂, NP Mavrovo, Korab, Korabska jezero, Kobilino pole, 2080-2180 m, 41°46'42"N, 20°34'55"E, 28 Jul. - 1 Aug. 2011, leg. Huemer & Tarmann, DNA Barcode TLMF Lep 05274 ( TLMF). Russia: 13 ♂♂, Altai Republic, Kosh-Agach distr., 17 km NNE Kokorya vill., Talduair Mt., valley of Sajlyugem river, 2200 m, 50°01'N, 89°14'E, 30 Jul. - 2 Aug. 2016, leg. Huemer & Wiesmair, DNA Barcodes TLMF Lep 20329, 20330, 20331, gen. slides GEL 1259 ♂ P. Huemer, GEL 1260 ♂ P. Huemer; 1 ♂, Altai Republic, Kosh-Agach distr., Northern part of Ukok plateau, 2400-2500 m, 49°30'N, 88°05'E, 4-6 Aug. 2016, leg. Huemer & Wiesmair; 11 ♂♂, 1 ♀, Altai Republic, Ulagan distr., 10 km NE Aktash vill., Kuraj Mts. Range, 2150 m, 50°19'N, 87°43'E, 6-8 Aug. 2016, leg. Huemer & Wiesmair; 8 ♂♂, Altai Republic, Ulagan distr., 11 km NNW Aktash vill., Ajgulak Mts.Range, 1900 m, 50°25'N, 87° 34'E, 28-30 Jul. 2016, leg. Huemer & Wiesmair; 1 ♂, Burytia, Barguzin valley, Djirga st., 600 m, 54°55'N, 111°14'E, 10 Jul. 1996, leg. Jalava & Kullberg (all TLMF).

Diagnosis.

C. arenariella is, besides C. lamai , the smallest and darkest species of the C. schleichi species group, with the white markings and brown scales reduced in many specimens. It differs from C. schleichi by the brown rather than cream-white head, thorax and tegulae but cannot be reliably separated from the other species of the complex by external characters. However, the male genitalia are characterized by the shape of the valva, particularly the long, pointed dorsal process, only shared with C. improvisella , C. messneri , and C. lamai . This process is more slender and longer than in C. improvisella and C. messneri whereas the male genitalia differ from C. lamai by the broader sacculus and the more slender and longer digitate medial processes of the vinculum. The female genitalia are hardly discernible from other species of the C. schleichi species group, except for the signum with a slender and long crescent-shaped base, a character only shared with C. lamai , and the particularly short apophysis posterior. However, the individual variation of this character is insufficiently documented due to lack of material.

Description.

Adult (Figs 7 , 8 ). Forewing length ♂ 4.0-5.0 mm, ♀ 3.5-4.5 mm. Head dark grey-brown, mottled with light grey, frons greyish white; labial palpus dark brown, second segment cream-white on inner surface, third segment blackish, mottled with white; antenna black, weakly ringed paler. Thorax and tegula dark grey-brown. Abdomen dark grey on ventral surface. Forewing dark brown with some light mottling, particularly on dorsum; distinct white markings: narrow transverse fascia from fold to costa at one-fifth, irregular white medial spot, separate costal and tornal spots; fringes basally dark brown, distal part lighter. Hindwing light grey.

Variation.

Specimens from Macedonia are larger (6.0 mm) and together with parts of Russian material exhibit some light mottling on the thorax and extended cream-white mottling of the forewing, particularly the dorsal area.

Male genitalia

(Figs 17 , 25 ). Uncus broadly sub-quadrangular, posterior corners rounded; lateral sclerites of gnathos distinct, medial part with large minutely spined culcitula; tegumen weakly widened anteriorly, with slightly emarginated anterior margin; transtilla sclerotized, longitudinally folded; pedunculus large, sub-triangular, with sclerotized inner edge; valva nearly straight, long, distal part moderately slender, weakly dilated with straight dorsal and ventral edges, apex with two processes, long and pointed dorsal process extended to posterior third of uncus, broadly digitate ventral process at about right-angles to dorsal process; sacculus moderately long, slender, with parallel margins, apically pointed; posterior margin of vinculum deeply incised medially, with pair of moderately short digitate processes, pair of latero-medial processes broadly projected; saccus slightly longer than valva, slender, gradually tapered to apex; phallus long, slender, nearly straight, apically with area of small cornuti.

Female genitalia

(Figs 32 , 39 , 46 ). Apophysis posterior about 3.5 times length of apophysis anterior; segment VIII without processes, smooth; ostium bursae with short lateral folds; apophysis anterior about length of segment VIII; antrum short, about one-fifth length of apophysis anterior, funnel-shaped; posterior part of ductus bursae with pair of long lateral sclerites extending to about apex of apophysis anterior, membranous part of ductus bursae about length of segment VIII including apophysis anterior; signum on right side of entrance to sub-oval corpus bursae, with slender and long crescent-shaped base and long slender hook.

Molecular data.

BIN: BOLD:AAE9479. The intraspecific average distance of the barcode region is 0.6%, the maximum distance 1.31% (p-dist) (n = 10). The minimum distance to the nearest neighbor, C. messneri , is 2.25%.

Distribution

(Fig. 1 ). Only known from scattered localities in Sweden, Finland, the Baltic countries ( Aarvik et al. 2017), North Macedonia, and from southern Siberia.

Bionomics.

The larva has been recorded in May, feeding in the stem of Dianthus arenarius L. which becomes gall-like stout and swollen ( Benander 1926). Pupation takes place outside the gall on the ground surface. However, according to Mutanen (in litt.) larvae live within the stems, without causing a conspicuous swollen gall. In the field moths have been collected from late June to early September at artificial light sources.

Remarks.

Lita arenariella was described from an unspecified number of specimens and no syntypes have been traced. However, the detailed description of the moth, genitalia and biology ( Benander 1926) leave no doubt about the identity of this species. The taxon was re-instated at species level by Aarvik et al. (2017).

Figures

Figure 1. Distribution map of successfully sequenced material of the C. schleichi species group. Map created with SimpleMappr (http: // www. simplemappr. net).

Figures 3 - 8. Adults. 3 Caryocolum schleichi, male, Syria; 4 C. dianthella, male, Spain; 5 C. improvisella, male, Austria; 6 C. improvisella, female, Austria; 7 C. arenariella, male, Sweden; 8 C. arenariella, female, Sweden.

Figures 17 - 20. Male genitalia. 17 Caryocolum arenariella, Russia, slide GEL 1260 P. Huemer; 18 C. messneri, holotype, Italy, slide GEL 1255; 19 C. lamai, paratype, Italy, slide GEL 1258 P. Huemer; 21 C. habeleri, paratype, France, slide GEL 1289 P. Huemer.

Figures 25 - 28. Male genitalia (details vinculum-valva-complex). 25 Caryocolum arenariella, Russia, slide GEL 1260 P. Huemer; 26 C. messneri, holotype, Italy, slide GEL 1255; 27 C. lamai, paratype, Italy, slide GEL 1258 P. Huemer; 28 C. habeleri, paratype, France, slide GEL 1289 P. Huemer.

Figures 31, 32. Female genitalia. 31 Caryocolum improvisella, Italy, slide GEL 1291 P. Huemer; 32 C. arenariella, Sweden, slide GEL 1292 P. Huemer.

Figures 36 - 39. Female genitalia (segment VIII). 36 Caryocolum schleichi, Syria, slide GU 86 / 277 P. Huemer; 37 C. dianthella, Spain, slide GEL 1285 P. Huemer; 38 C. improvisella, Italy, slide GEL 1291 P. Huemer; 39 C. arenariella, Sweden, slide GEL 1292 P. Huemer.

Figures 43 - 46. Female genitalia (signum). 43 Caryocolum schleichi, Syria, slide GU 86 / 277 P. Huemer; 44 C. dianthella, Spain, slide GEL 1285 P. Huemer; 45 C. improvisella, Italy, slide GEL 1291 P. Huemer; 46 C. arenariella, Sweden, slide GEL 1292 P. Huemer.