Stigmella eberhardi

Diagnostic description: 

Diagnosis. Males usually easy to recognise by the pale head and dark bronzy brown androconials; faded specimens may somewhat resemble S. roborella or pale headed S. samiatella (particularly in Spain). Sicilian S. roborella has androconials very similar to those of eberhardi. S. dorsiguttella has paler brown or orange-yellow androconials and also a clear androconial patch on basal 2/3 of forewing underside. Female very similar to S. roborella, but ovipositor not pointed.
Male genitalia resemble S. roborella, but valva with rounded inner lobe and aedeagus with broader anterior part and more clearly contorted vesica Female genitalia with accessory sac very distinctly contorted, unmistakeable.

Morphology: 

Description. Male. Forewing length 2.3-3.1 mm, wingspan 5.0-6.8 mm. Frontal tuft yellowish white, ochreous or occasionally mixed white and brown, scape and collar white, antenna with 33-40 segments. Thorax and forewings dark bronze brown with faint bronze reflections; underside bluish black. Hindwing covered with almost bluish black androconial scales; underside bluish black. Abdomen brown, anal tufts yellowish, inserted on well sclerotized plates.
Female. Forewing length 2.1-2.6 mm; wingspan 4.9-5.6 mm. Antenna with 25-31 segments. As male, but hindwings and underside of wings grey; abdomen without pointed tip.
Male genitalia. Vinculum anteriorly slightly bilobed. Uncus with triangular, widely separated horns. Gnathos with long and thin, widely separate processes. Valva with pointed distal process of about 1/3 valval length, inner lobe gradually rounded; sublateral processes about 1/3 transtilla length. Aedeagus long, basally widened; vesica coiled, forming almost a complete coil, with several groups of cornuti, anteriorly a group of long ones, more posteriorly the cornuti becoming shorter; manica not very conspicuous, only covering distalmost part of aedeagus.
Female genitalia. Accessory sac distinctly coiled, forming up to four coils, covered with many spines, except in anteriormost part. Ductus spermathecae with about 5 convolutions.

Associations: 

Hostplants. Quercus ilex, Q. petraea, Q. pubescens, Q. pyrenaica, Q. robur, Q. suber. Rare on the evergreen oaks (Q. ilex and suber), and only on teneral leaves of these.
Leafmine. A gallery with thin frass throughout. Egg usually on leaf upperside. Larva yellow. Mine almost indistinguishable from that of S. atricapitella or roborella.

Distribution: 

A southern species, widespread in Mediterranean region and reaching southern Central Europe. Positively recorded from Czech Republic and Slovakia (A. & Z. Laštuvka1990), Austria (Kasy 1979), Hungary, south-eastern France, Spain (Vives Moreno 1991), Portugal, Italy, Sardinia, Slovenia (new record), Croatia (new record), Macedonia (new record), Greece (Van Nieukerken 1996), Turkey (new record). The record from northern France (Gibeaux 1999) is not accepted, as it may have been S. samiatella. Surprisingly as yet not recorded from Sicily, where it seems to be replaced by a form of S. roborella with hindwings as in eberhardi. Not yet found in North Africa. Highest altitude: 1500 m in Turkey.

Life cycle: 

Life-history. Bivoltine, or possibly continuously brooded in south, larvae found in February (Andalusia: on Q. suber) and late May to December (on deciduous oaks), adults taken in April-September.

Citation: 

This taxonomic description is based on Van Nieukerken (2003).

Scratchpads developed and conceived by (alphabetical): Ed Baker, Katherine Bouton Alice Heaton Dimitris Koureas, Laurence Livermore, Dave Roberts, Simon Rycroft, Ben Scott, Vince Smith