Anarsia lineatella Zeller, 1839

Gregersen, Keld & Karsholt, Ole, 2017, Taxonomic confusion around the Peach Twig Borer, Anarsialineatella Zeller, 1839, with description of a new species (Lepidoptera, Gelechiidae), Nota Lepidopterologica 40 (1), pp. 65-85 : 74-78

Anarsia lineatella Zeller, 1839

Anarsia lineatella Zeller, 1839: 190 (nomen protectum)

Tinea pullatella Hübner, 1796: 63, pl. 17, fig. 118 (nomen oblitum)

Anarsia? pruniella Clemens, 1860: 169.

Anarsia lineatella heratella Amsel, 1967: 20. Subspecies.

Anarsia lineatella tauricella Amsel, 1967: 20. Subspecies.

Type material.

A. lineatella , holotype, ♀, with 9 labels (Fig. 1).

A. lineatella heratella, holotype, ♂: "AFGHANISTAN Herat 970 m 5.5.1956 H. G. Amsel leg." "Holotypus ♂ leg H. Amsel Anarsia lineatella heratella " | "Gen. præp. nr. 5296♂, O. Karsholt". Paratypes. 3♀, same data as holotype but genitalia slide 5295, 5297 (LNK).

A. lineatella tauricella, holotype, ♂: "Syr. sept. Taurus D Marasch VI 29" | "Holotypus ♂ leg. H. Amsel Anarsia lineatella tauricella " | "Gen. præp. nr. 5300♂, O. Karsholt" | "Coll. Osthelder" (ZSM). Paratypes. 1♀, "Syria sept. Taurus Marasch 1200 m 19.V.1928 L. Osthelder leg." | "AlloTypus ♀ leg. H. Amsel Anarsia lineatella tauricella " | "Gen. præp. nr. 5301♀, O. Karsholt" | “561” (ZSM); 1♂, same data as holotype, but genitalia slide 3868 (LNK).

Other material studied. Bulgaria (3♂, 7♀), Cyprus (1♂, 1♀), Denmark (4♀) (introduced), Germany (4♂, 10♀), Greece (4♂, 7♀), Hungary (5♂, 1♀), Israel (1♂), Libya (2♂, 1♀), Morocco (3♂, 4♀), Romania (1♂), Spain (7♂, 2♀), Spain, Canary Islands (1♀), Turkey (2♂, 1♀), Ukraine (1♂).

Diagnosis.

Anarsia lineatella is characterized by its fuscous grey forewing with only a little white and with indistinct black streaks; it appears darker than A. innoxiella and has a less fractured pattern of the forewings. For separation from A. innoxiella see under that species.

The male genitalia are characterized by 1) the flatly rounded shape of the sub-apical lobe of the left valva, 2) the rather slender shape of the uncus, and 3) the comparatively broad tegumen with its distinctly sinuous margins. These characters separate A. lineatella from A. innoxiella . The female genitalia differ from those of A. innoxiella by having two or three distinct ridges articulating distad from the middle of a sclerotised arch of the tergum.

Description.

Adult (Fig. 5e, f). Male. Wingspan 11-15 mm. Segment 2 of labial palpus with sub-rectangular scale tuft, black, mottled with whitish grey on upper and inner surface; segment 3 reduced. Antenna light grey, indistinctly ringed with blackish grey. Head light grey mottled with dark grey; frons lighter; thorax and tegula dark grey. Forewing fuscous grey, mottled with some light grey; costa with five small blackish spots separated by whitish grey, the spot at 1/2 most distinct; a broadly elongate black spot in middle of wing followed by white; veins with interrupted black scales; fringe whitish grey at base, darker grey beyond black fringe line. Hindwing grey with grey fringe. Female. Segment 2 of labial palpus with a distinct ventral brush; segment 3 longer than segment 2, thin, whitish grey with broad, black ring in middle and some black at base and tip. Otherwise similar to male.

Variation. The nominotypical subspecies is rather uniform, showing only slight variation. Segment 3 of the labial palpi in females can have more or less black. The wingspan of a series of specimens of both sexes from Morocco is smaller than average (11-12 mm), but otherwise similar to European specimens. Specimens from Afghanistan ( A. lineatella subsp. heratella) are characterized by having head, thorax, and basal half of the antennae whitish. The wing markings are similar to those of typical A. lineatella , but the forewings are somewhat bi-coloured, having a lighter costal third and a darker dorsal two-thirds. Specimens from southern Turkey are relatively small (about 11 mm) and generally paler grey compared with typical A. lineatella . Such specimens have been described as A. lineatella subsp. tauricella. See also under ‘Remarks’ below for these two subspecies.

Male genitalia (Figs 11a, b, 12a). Tergum IX-X truncate, rather broad, lateral margin distinctly sinuous; uncus conical, comparatively slender, with tiny distal tip; gnathos and culcitula absent; parategminal sclerites almost round, without coremata; sternum IX strongly asymmetrical, left valva truncate, sub-apical lobe flatly rounded, bearing long, slender, pointed tubular process; right valva large, broadly sub-triangular, bearing very long, pointed, moderately curved, tubular process; single small, sub-triangular, slightly setose lobe near vinculum on left side, juxta lobes small, setose; phallus ankylosed to juxta, without coecum, phallic trunk flat, bent dorsally, apex rounded.

Female genitalia (Figs 7b, 9c, d). Papillae anales elongate, apophyses posteriores moderate in length; apophyses anteriores very short; segment VIII cylindrical, evenly sclerotised, laterally slightly elevated; strongly sclerotised concave arch at anterior margin of tergum medially notched; two or three distinct ridges articulate distad from middle of arch at tergum, extended to middle of segment; antrum tilted, funnel-shaped; ostium bursae with ventral part crescent-shaped, sharply defined, dorsal part wrinkled, widely extended caudad; ductus bursae slender, straight; colliculum absent; ductus seminalis arising from transition between ductus and corpus bursae; signum sub-rectangular plate with strongly serrate margins; sac-like formation in segment IX anteriad of papillae anales - and similar formation distad of segment VII.

Bionomics.

The larva has (the rather small) head and prothoracic plate glistening black; the body is honey-brown or chestnut brown, with intersegmental divisions whitish; pinacula small, black, each with one whitish hair; anal plate glistening black; prolegs concolorous with body (Fischer von Röslerstamm 1842; Heckford 1992).

The species feeds on a number of Rosaceae , especially Prunus L. species. CABI (2016) lists Prunus armeniaca L., P. domestica L., P. dulcis (Mill.) D.A. Webb, P. persica (L.) Batsch and P. salicina Lind. as main host plants, and additionally Malus domestica Borkh. and Pyrus communis L. Piskunov (1990: 974) adds Prunus cerasus L. and P. spinosa L. He also lists Diospyros ( Ebenaceae ), which is an unlikely host plant of A. lineatella , and Acer tataricum L., which is probably a host plant of A. innoxiella . According to Piskunov (1990: 974, 899, fig. 611.3) the larvae of A. lineatella have also been reported to consume galls of the plum gall mite ( Eriophyes phloecoptes Nal.).

In early spring the young larva of the first brood bores into a shoot from below the pith and hollows it out causing exudation of some sap; the shoot withers and the larva moves to a new one. Larvae of the second brood bore into the pulp of the fruit, causing serious damage; the entrance hole is inconspicuous, but the fruit becomes discoloured and matures too early. The larva pupates in a light web on the ground or between leaves; from the latter most often hymenopterous parasitoids emerge (Fischer von Röslerstamm 1842: 283). A. lineatella is a serious pest on cultivated Prunus in subtropical areas of western Eurasia and North America. In Central Europe the adults fly in two generations a year, from May to July and again during August and September ( Kocourek et al. 1996). Further to the south and in the western USA there are 3-4 generations a year (Damos and Savopoulou-Soultani 2008: 467).

Distribution.

Widespread in Central and southern Europe and North Africa, eastwards through the Middle East and Turkey to Central Asia and China (Li and Zheng 1997: 122). A. lineatella has been introduced with its host plants to North America where it was present already in the middle of the 19th century ( Clemens 1860). It now occurs all over the USA and southern Canada. Records from other areas need confirmation because of confusion with similar looking species. In Europe the northernmost occurrence seems to be in northern central Germany (Niedersachsen, Nordrhein-Westfalen, and Brandenburg). Records from further north in Europe - and from other parts of the world - are either the result of introductions of fruits or - in most cases - misidentifications of A. innoxiella .

Remarks.

Anarsia lineatella was described from one male from Austria, Wien, in the collection of Fischer von Röslerstamm (" Lineatella FR"). Whereas the original description by Zeller was very short, Fischer von Röslerstamm (1842: 282-284, pls 95-96) gave a detailed and for that time very good illustrated description of adult, larva, pupa, and life history. It leaves no doubt that he was dealing with the species which is injurious to Prunus spp.

Tinea pullatella was described from an unstated number of specimens from Austria. The type material is probably lost. Hübner’s colour painting of pullatella is small, dark, and schematic, and not clearly associated with any species. Hübner (1825: 415) placed pullatella in his genus Gelechia , together with notatella, rhombella, proximella, and mulinella. The first author to deal with pullatella was Treitschke (1833: 95), who gave a re-description which matches A. lineatella . Additionally, he wrote that Geyer (1831: pl. 491) - in the continuation of Hübner’s works - figured "eine kleine, haarige, braunschwarze Raupe aus Spartium " (a small, hairy, blackish brown larva on broom) (Treitschke 1835: 199, 299). The larva figured by Geyer (who misspelled its name “pulatella”) probably belongs to Anarsia spartiella (Schrank, 1802) and is a misidentification as figure 188 in the above mentioned work by Hübner does not fit A. spartiella or any other Anarsia species.

Treitschke’s interpretation of Tinea pullatella Hübner was not followed by his contemporaries Zeller and Fischer von Röslerstamm, who did not even discuss that species in connection with their description of Anarsia lineatella .

Later Herrich-Schäffer (1855: 153) wrote under Anarsia lineatella : " Pullatella H. 118 stellt diese Art ziemlich kenntlich dar" ( Pullatella H.[ übner, fig.] 188 depicts this species quite recognizably rather well"). After that time Anarsia pullatella was to our knowledge only used as a valid name by Mann (1861: 190, 1862: 400), who later (e.g., Mann 1866: 355) used A. lineatella for this species.

Tinea pullatella has been out of use for over 150 years (nomen oblitum), and therefore we herewith propose to conserve the name Anarsia lineatella (nomen protectum) and suppress T. pullatella according to the provisions of Article 23.9 ( ICZN 1999). Appendix 1 lists 28 references by more than ten different authors that have used A. lineatella in the last 50 years.

Anarsia pruniella was described from an unstated number of specimens bred from larvae found 16th June 1860 on Prunus ( “plum”) at Philadelphia, USA ( Clemens 1860: 170).

Anarsia lineatella heratella was described from a series of 9 males and 21 females from Herat in Afghanistan, plus one further female from the Paghman Mts (also in Afghanistan), and two worn specimens from the Muk Pass in Iran. Herat is situated at an altitude of 923 m, but the two other localities are at about 3000 m altitude, and Amsel (1967: 20) referred the specimens from Iran to his subsp. heratella with some reservation.

We have examined the holotype and three female paratypes from Herat (see Figs 5g, h, 12b) and compared them with material from south-east Europe and the Middle East. They look admittedly different from other specimens of Anarsia from that region, but it has not been possible to observe any clear difference in the genitalia between the type material of subsp. heratella and A. lineatella sensu stricto. As we have no sufficient basis for changing the taxonomic status of subsp. heratella we retain it as a subspecies of A. lineatella .

In his description of A. lineatella heratella, Amsel (op cit.) refers to figures of its male and female genitalia ("Taf. 7 Fig. 9" and "Taf. 10 Fig. 26"). That reference has been copied into later literature, e.g., Ponomarenko (2009: 341), but the figures are based on German specimens and not of the Afghan subspecies.

Anarsia lineatella tauricella was described from three males and one female from Marasch (now Kahramanmaraş) in Turkey. The country of origin was given as Syria by Amsel (1967: 20), apparently because Marasch was part of Syria when the specimens were collected. We have examined the holotype and two paratypes. The three specimens are similar in external appearance (Fig. 5i, j), with the head and thorax whitish grey, mottled with dark grey, and the ground colour of the forewing light grey overlaid with darker grey. Whereas the genitalia of the allotype are similar to those of other females studied by us, the male genitalia of the two studied specimens (Fig. 12c,d) show some variation. In the holotype the lobe of the left valva is evenly convex (as in typical A. lineatella ) whilst the paratype has a larger, somewhat rectangular lobe. A similarly shaped lobe is present in Anarsia specimens examined from Israel and south-easternmost Europe examined by us. We find it possible that it represents a further, undescribed species, but due to insufficient material we refrain from describing it here.

Leraut (1980: 80) listed Lampros (Eupleuris) albilineella Bruand d’Uzelle, 1859 as a synonym of Anarsia lineatella . It is, however, an unnecessary replacement name of Isophrictis lineatellus (Zeller, 1850).