35.0531 Isophrictis anthemidella (Wocke, 1871)
Status and Distribution
Two females were attracted to MV light between 0100 and 0400hrs on 26 June 2020 at Sandwich Bay, Kent. Although recent immigration could not be excluded, reasons are given that suggest, on balance, these two moths form part of a resident population in this area (Sterling, Sattler & Lees, 2022).
At that time, searches in collections, including that of the NHMUK, failed to locate any further British specimens.
The species was subsequently recorded at light in Westleton, Suffolk on 19 June 2023.
In light of these records, the possibility of this species being encountered, in at least East and South-East England, and possibly more widely, should be borne in mind when identifying Isophrictis specimens. Sterling, Sattler & Lees (2022) recommend that external diagnosis of Isophrictis anthemidella and I. striatella needs confirmation by dissection or DNA barcoding.
Provisional map
Foodplant and Larval Feeding Signs
Foodplant not recorded in Britain. In Europe, it has been noted on Anthemis tinctoria, Tanacetum corymbosum, Anthemis cotula and Achillea ptarmica (Gregersen & Karsholt, 2022).
Searches of the abundant, related, Achillea millefolium for larvae at the Kent site, proved unsuccessful (Sterling, Sattler and Lees, 2022).
Habitat
Possibly established on coastal links at a site in Kent.
Finding the Moth
Larva: not known in Britain. In Europe, can be found in flower/seedheads where it hibernates overwinter.
Similar Species
Externally, very similar to I. striatella, but on average slightly larger (wingspan 12-15mm as opposed to 11-13, occasionally 14mm). I. striatella has a reddish-brown ground colour compared to a paler greyish-brown in I. anthemidella. Additionally, I. anthemidella usually has a elongate patch of paler grey scaling above the silver medio-basal streak, not observed to be present in I. striatella. The black first line in the cilia of I. anthemidella curves outward medially whereas the corresponding line in I. striatella is straighter. The ventral tuft on the second segment of the labial palp is white mixed with pale brown in I. anthemidella whereas it is white mixed with dark brown is I. striatella (Sterling, Sattler and Lees, 2022). Genitalia features to separate the two are easiest in females.