Immature stages of Stegosatyrus ocelloides (Nymphalidae: Euptychiina), a grassland specialist butterfly

Abstract

The immature stages are described for Stegosatyrus ocelloides (Schaus, 1902), a butterfly species associated with open vegetation formations, such as grasslands and savannas, in the southern Neotropics, and additional information on the eggs and first and second instars of Stegosatyrus periphas (Godart, [1824]) are provided. In both species the eggs are barrel-shaped, with the chorion poorly marked with small concavities giving it a “golf ball” appearance, and light cream, with conspicuous broad darker stripes that turn to bright red after few days. The first instars are light cream with reddish longitudinal stripes and the head is black bearing a pair of very short scoli. The caterpillars of S. ocelloides pass through four instars, and occasionally show an additional fifth instar. The last instars are slender with a pair of short caudal filaments on the last segment, laterally striped with white and dark and light brown longitudinal lines and a dark brown head with a pair of short scoli. The pupae are elongated, rusty brown with silvery patches on the dorsal and lateral abdomen, with pointed projections on the head and insertion of the alar caps and marked dorsal carinae on the first abdominal segments. In general, the immature stages are distinct from all other species of the “Megisto clade”, of which the genus Stegosatyrus Zacca, Mielke & Pyrcz, 2013 is part.