22-8-2021 SPACE MUSEUM, CUENCA - CHECKERSPOT BUTTERFLY (Castilia perilla)

The tribe Melitaeini is of worldwide distribution. It includes the Crescents and Checkerspots of North America, and many familiar European species such as the Marsh, Spotted and Heath Fritillaries.

Castilia are very closely related to Eresia, Anthanassa and Janatella, so closely in fact that these genera can only be distinguished by microscopic examination of the male genitalia.

The 13 Castilia species fall into 2 distinct groups. The first group includes ofella, myia and angusta, all of which have whitish spots on the forewings and a broad white or creamy median band on the hindwings. These markings are repeated on the underside which is yellowish and has a series of crescents around the hindwing margins. The second group includes castilla, northbrundii, neria and perilla, all of which have blackish wings marked with patches of orange. The under surface of their hindwings is dark brown, with the veins  picked out in black. These butterflies are very convincing Batesian mimics of Altinote species. The latter are toxic / unpalatable to birds, so the similarity of markings undoubtedly provides the Castilia species with a degree of protection against predation.

Castilia perilla occurs in several different colour forms, and it is quite common to find two or more forms of this species flying at any given site. Each form mimics a different Altinote or Abananote species, e.g. acraeina is a mimic of Altinote negra euclia, and aricilla mimics Abananote erinome.

The butterfly is common and widely distributed in Ecuador, Bolivia, Brazil and Peru.