37.029 Coleophora orbitella (Pale Birch Case-bearer)
ws: 10.5-14mm; May-Jun; birch (Betula spp), alder (Alnus spp); NS-B - local in birch heaths and alder carrs throughout Britain
Coleophora orbitella §1 female
ID: Plain forewing; antenna white ringed fuscous to beyond half its length and without significant thickening of its proximal segments > 21 species
Male genitalia: Sacculus without a posterior process; sacculus with ventral margin rolled to form a bar; apex of sacculus not produced into a curved point, aedeagus without a serrate or a very acute apex > 4 species
In C.potentillae and C.ahenella the antenna is ringed to or almost to the apex. In C.orbitella and C.binderella the antennae is ringed in the basal half and indistinctly ringed in the apical half. C.orbitella has a fuscous forewing with ws:10.5-14mm, C.binderella has a ferruginous-brown forewing with ws:8-12mm.
Female genitalia: Signum very large; spike <1/2 length of bursa copulatrix; short heavily scobinate section of ductus bursae from its junction with introitus vaginae; ostium opens as a pouch near anterior margin of subgenital plate; short stout spines along posterior margin of subgenital plate.
Male genitalia: Sacculus without a posterior process; sacculus with ventral margin rolled to form a bar; apex of sacculus not produced into a curved point, aedeagus without a serrate or a very acute apex > 4 species
In C.potentillae and C.ahenella the antenna is ringed to or almost to the apex. In C.orbitella and C.binderella the antennae is ringed in the basal half and indistinctly ringed in the apical half. C.orbitella has a fuscous forewing with ws:10.5-14mm, C.binderella has a ferruginous-brown forewing with ws:8-12mm.
Female genitalia: Signum very large; spike <1/2 length of bursa copulatrix; short heavily scobinate section of ductus bursae from its junction with introitus vaginae; ostium opens as a pouch near anterior margin of subgenital plate; short stout spines along posterior margin of subgenital plate.
Dissection
Female genitalia
§1 Bookham Common, Surrey; 16/07/2013; female; fw 6.3mm
All images © Chris Lewis
All images © Chris Lewis
Page published 29/11/2013 (§1)
