35.053 Isophrictis striatella (Tansy Stem-borer)
ws: 11-13mm (MBGBI4.2), fw: 6-8mm (Sterling & Parsons); Jul-Aug; tansy (Tanacetum vulgare), sneezewort (Achillea ptarmica); NS-B local south of Wash-Severn line
Isophrictis striatella §1 female (image provided by Gavin Price)
ID: Forewing brown; a white basal streak that approaches the dorsum at ⅗, often interrupted by a black mark at ~½; a black spot at ¾; a diagnoal white line from the costa at ⅘ to the termen; 2 or 3 white preapical dashes.
As far as I can see from comparison of web images, I.anthemidella (new to Britain in 2023) is indistinguishable from I.striatella on external features.
Male genitalia:
Female genitalia: I.anthemidella has an additional long straight sclerotised section in the posterior half of the ductus bursae.
As far as I can see from comparison of web images, I.anthemidella (new to Britain in 2023) is indistinguishable from I.striatella on external features.
Male genitalia:
Female genitalia: I.anthemidella has an additional long straight sclerotised section in the posterior half of the ductus bursae.
§1 Weeleyhall Wood, Essex; 25/07/2025; female; fw 6.2mm; specimen obtained by Gavin Price
All images © Chris Lewis
All images © Chris Lewis
Page published 17/09/2025 (§1)
