Coleophora nepetellae Baldizzone & Nel

Baldizzone, Giorgio, Nel, Jacques & Landry, Jean-Francois, 2014, Coleophoranepetellae Baldizzone & Nel, a new species of the C. lixella group (Lepidoptera, Coleophoridae) from France and Italy, ZooKeys 459, pp. 119-135 : 120-124

Taxon classification Animalia Lepidoptera Coleophoridae

Coleophora nepetellae Baldizzone & Nel sp. n.

Type material.

Holotype ♂ (genitalia slide Bldz 15711): [Italy] "PIEMONTE |V.[alle] Varaita | Pontechianale (CN) | Grangia del Rio 2000 m | 30-VII-2012 | G. Baldizzone leg."; "Database # | CNCLEP | 00110051"; "Barcode of Life Project | Leg(s) removed | DNA extracted" [blue]. In coll. Baldizzone, Asti.

Paratypes: Italy: 14 ♂, 12 ♀, Piemonte, same locality and date as holotype, coll. Baldizzone, barcoded specimens # CNCLEP00110052-CNCLEP00110060; 14 ♂♂ (genitalia slide Bldz 15535), 12 ♀ (genitalia slide Bldz 15536, 15712), ibidem, 2-VIII-2012, coll. Baldizzone; 4 ♂, 8 ♀, ibidem, 22.VII.2013, coll. Baldizzone; 1 ♂, ibidem, 2.VIII.1986, G. Bassi leg., coll. Bassi.

France: 1 ♀, Alpes-Maritimes, Le Pra sur Tinée, 1700 m, 44.3227°N, 6.8849°E, ex Nepeta nepetella , 23.VII.2000, J. Nel leg., coll. J. Nel, La Ciotat; 1 ♀, Alpes Maritimes, Roubion, 44.093°N, 7.0511°E, 1630 m, 9.VII.2011, Th. Varenne leg., coll. Th. Varenne, Nice; 1 ♂, Alpes-Maritimes, Tende, col de Tende, 44.15°N, 7.5667°E, 1830 m, 21.VII.1995, Th. Varenne leg., coll. Th. Varenne; 1 ♀, Alpes-Maritimes, Casterino, 44.0986°N, 7.5059°E, 2000 m, 13.VIII.2013, ex Nepeta nepetella , J. Nel leg., coll. J. Nel; 1 ♂, Alpes-de-Haute-Provence, St-Ours near Meyronnes, 44.4805°N, 6.8086°E, 15.VII.2005, 1800 m, leg. Jacques Nel, specimen # CNCLEP00033958, genitalia slide MIC 6834, barcoded, Canadian National Collection, Ottawa; 1 ♀, Alpes-de-Haute-Provence, 2 km E Meyronnes, 44.4711°N, 6.8086°E, 1575 m, 2.VII.2005, leg. C & FK Gielis, specimen # CNCLEP00029208, genitalia slide MIC 6835, barcoded, coll. H. van der Wolf, Netherlands.

Diagnosis.

Coleophora nepetellae is a relatively large Coleophora , whose forewings are predominantly yellow with fine silvery striae. It belongs to the Coleophora lixella species group and is most similar to Coleophora nevadella , both externally and in genitalia. The latter species was formerly known only from Spain (Vives Moreno 1991) but is here reported from France for the first time based on material collected by JN (see below).

Externally the adult of Coleophora nevadella from the Sierra Nevada (the type locality in Spain) (Fig. 2) is on average smaller than that of Coleophora nepetellae , its forewings are devoid of brown scales, and the silvery striae are inconspicuous or nearly absent. In male genitalia (Figs 6, 11), Coleophora nevadella has the valvula smaller with its outer margin more oblique and its ventral margin barely reaches the dorsal edge of the sacculus, whereas in Coleophora nepetellae the ventral margin of the valvula is extended nearly to the ventral edge of the sacculus. The apex of sacculus is more prominently bulged in Coleophora nepetellae than in Coleophora nevadella .

In female genitalia, Coleophora nepetellae is easily distinguished from Coleophora nevadella by the following differences: in Coleophora nevadella the colliculum is more elongate and has two long and thin lateral bars that are extended nearly to the distal margin of the sterigma (Fig. 12); these bars are very short in Coleophora nepetellae (Fig. 13); in Coleophora nevadella the median lamina in the ostium bursae is long, thin, and extended posterad of the ostium whereas in Coleophora nepetellae it is more robust, irregularly delineated and with sclerotized lateral extensions; finally the paired longitudinal bars of the sterigma are narrow with the inner margins smooth in Coleophora nevadella , whereas they are rough-edged with small, spinulose protuberances in Coleophora nepetellae .

Description.

Adult. Wingspan 22-26 mm. Head white shaded with yellow on vertex. Antenna with scape cream yellow, with thick tuft of erect, concolorous scales; flagellum white annulated with pale ochreous yellow, nearly indistinctly so on upper surface, dark brown on lower surface; basal third with elongate cream-coloured scales. Labial palp white, third article about as long as second; second article with long tuft of erect scales on ventral surface. Thorax white with a median cream yellow line; tegula cream with thin white border.

Forewing with apex falcate, curvature variable; ground colour cream yellow, paler in dorsal half, costal half slightly darker from scattering of brown scales, mainly in area between median line and costa; apical portion with 4-5 short, oblique silvery striae; one fine silvery stria in subcostal area near base, widening to quarter of wing and lined with brown on costal side; second silvery stria in median area from basal third to margin; third silvery stria along anal fold and interrupted before margin; fourth silvery stria along dorsal margin, very short and inconspicuous. Fringe dark cream-coloured along costal margin and around falcate apex; on dorsal margin, fringe pale grey with a line of pale cream basally. Hindwing grey, sometimes with brownish hue, fringe coloured as in forewing. Abdomen pale dirty white.

Abdominal apodemes (Fig. 8): Latero-anterior bars about twice as long as latero-posterior ones. Transverse bar long, proximal edge straight and thin, distal edge slightly convex around tergal sclerites. Tergal sclerites covered with conical spines, about 5 –6× longer than wide (on T3).

Male genitalia (Figs 6, 7, 11): Gnathos knob large, globose. Tegumen narrow, elongate, pedunculi slightly outwardly flared. Transtilla thin, linear. Valvula wide with rounded ventral margin. Cucullus large, markedly sclerotized, wider basally, obliquely oriented, dorsal side slightly convex and apex rounded. Phallotheca elongate-conical, ventral portion less sclerotized. Cornuti (Fig. 7) thin, tightly arranged in elongate bundle.

Female genitalia (Figs 9, 13): Papillae anales markedly sclerotized, elongate. Posterior apophysis twice as long as anterior one. Sterigma conical laterally with pair of longitudinal sclerotized, outcurved bars, curvature more pronounced on outer side, distal portion of bars parallel to each other. Ostium bursae calix-shaped. Widest distal section of colliculum with small conical spines, proximal section narrowed with lateral edges more sclerotized, median lamina extended from smooth, looped section of ductus bursae to widened portion of colliculum. Ductus bursae lined with short conical spinules from anterior end of colliculum to first loop (about 4 × length of sterigma); second loop without spinules (about 2 × length of sterigma); anteriormost section of ductus transparent, without ornamentation. Corpus bursae ovoid with distal half tapered, signum leaf-like.

L5 larva (Fig. 1): Length 9 mm. Body brown with faint brown dorsal line interrupted at segment junctions. Head shiny black. Thoracic shields shiny black; prothoracic shield wide, very finely cracked along median axis from middle to posterior edge; mesothoracic shield made up of two wide figs irregular in shape, separated by a median gap except thinly and narrowly joined anteriorly; metathoracic shield made up of two smaller figs separated by a gap, irregular in shape with denticulate inner edges. Spiracular sclerites shiny black, present on all thoracic segments: oblong on prothorax, oval on mesothorax and metathorax, largest in size on mesothorax. Thoracic legs entirely shiny black. Prolegs on A3-A6 with 5-7 crochets in two uniordinal rows. Anal fig shiny black. Anal proleg half-moon-shaped, each with 15-18 crochets. (Description based on larva from France, Alpes-de-Haute-Provence, Montagne de Lure, 1519 m, 31.V.2013, found on grass beside Nepeta nepetella , J. Nel leg.).

Derivation of specific epithet.

The species epithet is derived from the species name of its larval host, Nepeta nepetella .

Biology.

The host plant of Coleophora nepetellae is Nepeta nepetella L. ( Lamiaceae ). This plant has narrow, dentate, whitish green leaves, and large white, hairy corollas with the pistils extended beyond the chalices. This is a mountain plant that occurs throughout the southern Alps, in France mainly in the most sun-exposed parts of the foothills, between 1000 and 2000 m in elevation, along roads, at the base of screes, or near sheepfolds. It blooms between mid-June and late August, depending on elevation and exposure. Nepeta nepetella is the initial food plant from which the larva makes its first case. The second host plant which serves to construct the final case is a unidentified Poaceae .

Oviposition and larval development between late summer and overwintering was not observed directly but it can be inferred with much certainty that the eggs are deposited on or in the chalices, and that the young larvae build a case from a seed, as do all the other species of the lixella group for which the biology is known. Overwintering probably takes place on the ground or in the litter. In the spring, it was observed that the young larva lives in a case made from a hollowed-out piece of grass. Grasses used for case-making are species with broad leaves that grow in close proximity to Nepeta plants which become the larval host. This habit of using different host plants before and after overwintering is exceptional among leaf-mining Lepidoptera and occurs among all the species of the lixella group for which the biology is known. The case is not enlarged during larval development (as in Coleophora ornatipennella , for example) but is abandoned for a new, larger one at each instar. The final case (Fig. 5) is constructed from a piece of mined grass leaf which is hollowed out. It is 13-15 mm long, about 3 mm at its widest girth, straw-coloured, slightly darkened, with longitudinal ridges made by the veins from the leaf used in its construction; the oral opening is rounded, at 30°; the anal end has the terminal 3 mm dorso-ventrally flattened; the median portion is slightly broader, fusiform.

Phenology.

The species has one generation per year, with the adults emerging between July 20 and the first week of August in the Valle Varaita in Italy. In France at higher elevations adult emergence extends into the middle of August. In all locations adult flight coincides with the flowering of the host plant, Nepeta nepetella . The adults fly in bright sunshine, especially during the afternoon and take short flights among the flowering stems. The new species coexists with Coleophora lixella which flies among Thymus cf. serpyllum L. ( Lamiaceae ), its host plant.

Type locality.

Italy, Piemonte, Valle Varaita, Pontechianale, Grangia del Rio, 2000 m, 44.6625°N, 6.9939°E. The Grangia del Rio is a side valley of the Valle Varaita through which runs a tributary of the Varaita River. It is situated in the Cottian group of the Western Alps in northwestern Italy. The host plant, Nepeta nepetella , from which type material was obtained grows there within 30-40 feet of a pastoral trail and at the base of a rock slide.

Geographical distribution.

In Italy the species is known only from the type locality in the Piemont Region. In France, it is recorded from the Alpes-Maritimes, Upper Var, Alpes-de-Haute-Provence, Hautes-Alpes, Isère, the Drôme, and further to the west from the Vaucluse where it is common on the slopes of Mont Ventoux wherever Nepeta nepetella grows.

Records of Coleophora nevadella from France

In his Atlas of Coleophoridae of France, Nel (2001) recorded a species of the lixella group from the Eastern Pyrénées (Cerdagne area). He labelled it " Coleophora lixella ( Eupista ) cf. nevadella Baldizzone, 1985" (under his entry no 140c) and indicated that the identification was tentative. Coleophora nevadella was formerly known only from Spain (Vives Moreno 1991). Nel reported finding adults among Nepeta latifolia DC., a Lamiaceae distributed in the Iberian Peninsula which reaches its northern limit in southwestern France. We confirm here that Coleophora nevadella is indeed the species tentatively reported from France by Nel (2001). The adults occur in July on blooming Nepeta latifolia plants, which is the likely oviposition host plant.

Record details. 3 ♂, 2 ♀,: France, Pyrénées-Orientales, Mont-Louis, route D10 to Sauto 11.VII.1990, imagos on Nepeta latifolia , J. Nel leg.; 2 ♂, ditto, 28.VII.1993. 6 ♂, Pyrénées-Orientales, Védrignans, 1400 m, 16.VII.1992, imagos on Nepeta latifolia , J. Nel leg.; 1 ♀, ditto, 30.VII.1993 (Jacques Nel Collection and Tyroler Landemuseen, Innsbruck). 1 ♂, Porté-Puymorens, vallon de Passet, 1650 m, 17.VII.2004, T Varenne leg. (Thierry Varenne Collection, Nice).