General comments:
Ubiquitous resident.

Separation of this species from Dark-barred Twin-spot Carpet can be extremely difficult and has been discussed by Plant (2005). The Red-twin-spot usually has a red median band on the forewing, but in some forms this band can be very dark or almost black. The Dark-barred Twin-spot, as the common name implies, has the median band of the forewing dark - often black. However, there is a form that has a reddish band (actually the typical form - those with black bands being referable to ab. unidentaria). A very widely used character for the separation of the two has been the presence (in Dark-barred) or absence (in the Red) of a notch on the inner edge of the median fascia of the forewing at the costa. However, this character has now been proven to be unreliable and should not be used. In many cases it will be necessary to rub away the scales from the tip of the abdomen of male specimens in order to look at the genitalia with a hand lens. The two species are immediately and easily separated by the length and shape of the costal process that arises from the inner face of each valva. In X. spadicearia each process is long and narrow, produced from the tip of the valva and then turning inwards at 90 degrees so that the two often touch or even overlap. In X. ferrugata the costal process is short and stout, produced to a short point that scarcely extends beyond the tip of the valva. Both species have an exceptionally long, narrow and curved uncus which should not be confused with the costal processes of the valvae.

Recorded in 34 (83%) of 41 10k Squares. First Recorded in 1887. Last Recorded in 2024. Additional Stats

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