Coptodisca lucifluella

Morphology and recorded host plants.

Adult. External characters (Figs 2, 4). Length of forewing 1.5-1.8 mm including fringe. Head silvery grey, rest of body dark silvery grey. Basal half of forewing silvery grey, with two triangular patches present at distal thirds of costa and dorsum, white with black border on each side. Area between silvery grey basal field and tornal patch dark fuscous. Tornal patch broad, especially at base (Fig. 2).

Genitalia (Figs 7, 8). Male genitalia with five sensilla on pectinifers of both valvae (n = 2; right valva of an additional specimen lost, left valva with five teeth), elsewhere 5-7 sensilla (Bernardo et al. 2015, see fig. 7). Phallus with two rows of spines. Female genitalia with six oviscapt teeth, a pair of large ones anteriorly, posterior ones forming a wide, slightly indented apex (Fig. 8a). Corpus bursae rather pyriform, with neither scobinations nor signum (Fig. 8b).

Mine. This species prepares blotch mines visible on both sides of the leaf (Figs 9, 10). Mines are always situated between lateral veins and never traverse them. The shape of mines is rather elongate and angular (Fig. 10), average size 8 mm × 5 mm. Mines are positioned close to lateral veins, equally distributed from the midrib to the edge of the leaflet (Fig. 12). The frass of C. lucifluella is visible from both sides as it is dispersed in the mine (Fig. 9).

Larva. Mature larva 2.5 mm long, monochromatic rusty brown in colour (Fig. 14).

Case. Prepared from an oval-shaped area of the leaflet, severed from the leaf by chewing the epidermis on both sides around this piece (Fig. 19). Then the oval plates are attached with silk along the edges, forming an oval-shaped shield, which is somewhat more elongate than the original leaf pieces, 2.9 mm long and 1.3 mm wide (Fig. 18).

Pupa. Fresh pupa pale yellow, then becoming dark yellow, 2.7 mm long (Fig. 17).

Host plants. Host plants of C. lucifluella in Hungary are Juglans regia, Carya cordiformis and Pterocarya fraxinifolia (new hostplant record).

Remarks.

Genitalia images prepared by us have a resolution too low for publication, but the above-mentioned characters are still observable. We illustrate here the genitalia with images kindly sent by Erik J. van Nieukerken (Fig. 7a, b; partly from Bernardo et al. 2015).