Introduction
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 are dark brown, with the veins picked out in black.
Castilia castilla occurs as 2 subspecies – castilla from the central valley and eastern Andes, and occidentalis from the western Andes. It is a mimic of toxic Altinote species.
This butterfly is widespread in the Andes mountains of Colombia, and probably also occurs in Ecuador and Venezuela.
Habitats
Castilia castilla is found in cloudforests at elevations between about 600-2000m.
Lifecycle
The eggs of Castilia species are laid in batches of between 30-80 on the underside of leaves of the foodplants. They are laid in layers, a defence strategy that ensures that the bottom layer cannot be parasitised by Trichogrammatid wasps. The topmost eggs hatch first. The larvae then immediately eat their egg-shells, allowing those from the lower layers to hatch.
Castilia larvae feed gregariously on Acanthaceae, spinning a thin silk web over the leaves. In the early instars they eat only the leaf tissue, and skeletonise the leaves so that only the midrib, veins and cuticle remain. They are described by DeVries as being covered with dense bristles and with each segment bearing fleshy protuberances.
Adult behaviour
Males are usually seen singly flying in forest edge habitats, or imbibing mineralised moisture from road surfaces. They usually keep their wings fully outspread when feeding. Both sexes nectar at the flowers of Justicia and other Acanthaceae.