37.052 Coleophora ibipennella (Forest Case-bearer)
ws: 10-14mm; Jul - Aug; oak (Quercus spp); locally common in oak woods and oak scrub in SE.England, less common in SW.England
Coleophora ibipennella §1 male
ID: Forewing with ground colour white; antennal scape with a well-developed tuft > 5 species
All these species have: head white; antenna white ringed ochreous/fuscous to apex; labial palp S2 with moderate tuft; thorax white; fw costa finely edged blackish-fuscous near base; legs white, hindleg tarsal segments ringed dark fuscous at base (whether the other legs have tarsal segments ringed fuscous is not mentioned in MBGBI3 for any species except kuehnella where the midleg tarsal segments are also said to be ringed fuscous at base).
Any fuscous scales are found along the veins in ibipenella, kuehnella and betulella, but are scattered in anatipennella and albidella.
C. ibipennella and kuehnella have white-tipped costal cilia beyond a dark basal line. C.betulella has inner costal cilia white, outer costal cilia greyish-fuscous not contrasting with a dark basal line. C.kuehnella (ws 14-17mm) is larger than C.ibipennella.
Male genitalia of these species and C.currucipennella are similar - the key features are described and illustrated at Moth Dissection.
Interpretation is seriously hampered by difficulty in getting the genitalia to lay flat - this is particularly critical for the sacculus features.
C.anatipennella: valva short (about half as long as lower/ventral edge of sacculus); uncus broad tapering to a curved point; tegumen short, not constricted, somewhat tapering towards uncus; lateral edge of sacculus forming a long parallel-sided club reaching the valva; lower/ventral margin of sacculus straight; angle between lateral and ventral margins of sacculus obtuse (when laid flat the genitalia have an angular 'W'-shaped profile).
C.ibipennella: valva long (about as long as lower/ventral edge of sacculus); uncus tear-shaped, rounded at margin; tegumen constricted to give figure-of-8 profile; sacculus with extension at ventro-lateral corner; lateral margin straight, clubbed or bluntly pointed reaching valva; ventral margin straight; angle between lateral and ventral margins of sacculus 90 deg (when laid flat genitalia have an angular oblong profile).
C.palliatella (=kuehnella): valva long (about as long as lateral edge of sacculus; uncus triangular with bands of hairs leaving a clear margin at base; tegumen parallel-sided; lateral margin of sacculus terminates in a blunt tip well below valva; lower/ventral margin of sacculus concave (when genitalia laid flat).
C.betulella: valva long (longer than lateral edge but not as long as lower/ventral edge of sacculus); uncus eliptical with dark margins; tegumen almost parallel-sided; sacculus with small extension at ventro-lateral corner; lateral margin of sacculus with a twisted club which almost reaches the valva and gives the whole lateral margin a figure of 8 appearance when flat; lower/ventral margin evenly curved (convex).
C.albidella: valva long; uncus broad, rounded with flattened lower edge; sacculus with a triangular extension at ventro-lateral angle; lateral edge with a broad, curved club that doesn't reach the valva, ventral edge smoothly curved.
C.currucipennella: valva short; uncus broad, tapering to a curved point; tegumen short (only a little longer than wide); edge of sacculus evenly curved without a ventro-lateral angulation even when laid flat; sacculus ending in a slightly curved tapering club which just reaches the valva.
All these species have: head white; antenna white ringed ochreous/fuscous to apex; labial palp S2 with moderate tuft; thorax white; fw costa finely edged blackish-fuscous near base; legs white, hindleg tarsal segments ringed dark fuscous at base (whether the other legs have tarsal segments ringed fuscous is not mentioned in MBGBI3 for any species except kuehnella where the midleg tarsal segments are also said to be ringed fuscous at base).
Any fuscous scales are found along the veins in ibipenella, kuehnella and betulella, but are scattered in anatipennella and albidella.
C. ibipennella and kuehnella have white-tipped costal cilia beyond a dark basal line. C.betulella has inner costal cilia white, outer costal cilia greyish-fuscous not contrasting with a dark basal line. C.kuehnella (ws 14-17mm) is larger than C.ibipennella.
Male genitalia of these species and C.currucipennella are similar - the key features are described and illustrated at Moth Dissection.
Interpretation is seriously hampered by difficulty in getting the genitalia to lay flat - this is particularly critical for the sacculus features.
C.anatipennella: valva short (about half as long as lower/ventral edge of sacculus); uncus broad tapering to a curved point; tegumen short, not constricted, somewhat tapering towards uncus; lateral edge of sacculus forming a long parallel-sided club reaching the valva; lower/ventral margin of sacculus straight; angle between lateral and ventral margins of sacculus obtuse (when laid flat the genitalia have an angular 'W'-shaped profile).
C.ibipennella: valva long (about as long as lower/ventral edge of sacculus); uncus tear-shaped, rounded at margin; tegumen constricted to give figure-of-8 profile; sacculus with extension at ventro-lateral corner; lateral margin straight, clubbed or bluntly pointed reaching valva; ventral margin straight; angle between lateral and ventral margins of sacculus 90 deg (when laid flat genitalia have an angular oblong profile).
C.palliatella (=kuehnella): valva long (about as long as lateral edge of sacculus; uncus triangular with bands of hairs leaving a clear margin at base; tegumen parallel-sided; lateral margin of sacculus terminates in a blunt tip well below valva; lower/ventral margin of sacculus concave (when genitalia laid flat).
C.betulella: valva long (longer than lateral edge but not as long as lower/ventral edge of sacculus); uncus eliptical with dark margins; tegumen almost parallel-sided; sacculus with small extension at ventro-lateral corner; lateral margin of sacculus with a twisted club which almost reaches the valva and gives the whole lateral margin a figure of 8 appearance when flat; lower/ventral margin evenly curved (convex).
C.albidella: valva long; uncus broad, rounded with flattened lower edge; sacculus with a triangular extension at ventro-lateral angle; lateral edge with a broad, curved club that doesn't reach the valva, ventral edge smoothly curved.
C.currucipennella: valva short; uncus broad, tapering to a curved point; tegumen short (only a little longer than wide); edge of sacculus evenly curved without a ventro-lateral angulation even when laid flat; sacculus ending in a slightly curved tapering club which just reaches the valva.
Dissection
Male genitalia
§1 New Forest, Hampshire; 29/06/2009; male; fw 6.5mm
§2 Belfairs woods, Essex; 18/07/2014; male; fw 4.6mm (worn)
All images © Chris Lewis
§2 Belfairs woods, Essex; 18/07/2014; male; fw 4.6mm (worn)
All images © Chris Lewis
Page published March 2011 (§1) | §2 added 19/01/2015 (male genitalia only)
