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Three species of Saturniidae (Hemileucinae), all belonging to Periga Walker, 1855, are recognized as new and are described as: P. paranapiacaba sp. nov., P. faustinoi sp. nov., and P. intervales sp. nov. The Periga gueneei species-group is proposed to accommodate P. gueneei (Lemaire, 1973) and the new species P. intervales sp. n. described here. The status of another Saturniidae species is revised: Automeris intermedius (Bouvier, 1929), stat. rev., which is removed from the synonymy with A . nubila Walker, 1855. Habitus and illustrations of male genitalia are provided for all new species and both Automeris species. All holotypes are deposited in the Entomological Collection of the Oswaldo Cruz Institute, Rio de Janeiro, Rio de Janeiro, Brazil.

Biodiversity of tropical Saturniidae, as measured through traditionally described and catalogued species, strongly risks pooling cryptic species under one name. We examined the DNA barcodes, morphology, habitus and ecology of 32 ‘well known’ species of dry forest saturniid moths from Area de Conservacion Guanacaste (ACG) in north-western Costa Rica and found that they contain as many as 49 biological entities that are probably separate species. The most prominent splitting of traditional species – Eacles imperialis, Automeris zugana, Automeris tridens, Othorene verana, Hylesia dalina, Dirphia avia, Syssphinx molina, Syssphinx colla, and Syssphinx quadrilineata – is where one species was believed to breed in dry forest and rain forest, but is found to be two biological entities variously distinguishable by DNA barcodes and morphology, habitus, and/or microecological distribution. This implies that ‘standard’ biological information about each traditional species may be an unconscious mix of interspecific information, and begs renewed DNA barcoding, closer attention to so-called intraspecific variation, and increased museum collection and curation of specimens from more individual and ecologically characterised sites – as well as eventually more species descriptions. Simultaneously, this inclusion of sibling species as individual entities in biodiversity studies, rather than pooled under one traditional name, reduces the degree of ecological and evolutionary generalisation perceived by the observer.

The present study is concerned with the sequences of behaviour shown by a common Brazilian Saturniid moth, Automeris aurantiaca Weym, on emergence from the pupa (post-eclosion sequences) and in a simple experimental situation, in which display was induced repeatedly (display sequences). The sequences appear to have relatively little dependence on external stimuli, and in comparison with such material as the Salticid spiders studied by PRECHT (I952) and DREES (I952), whose behaviouriscontinuallydependent on and modified by constantly changing exteroceptive influences, their analysis is simple. The adult moths do not feed, and sexual responses may be inhibited by strong illumination; thus the number of interacting tendencies is limited. It was therefore hoped that an analysis of the relationships between the activities composing these sequences would make possible a hypothesis regarding their underlying organisation.

THE rhythmic rocking responses of Hemileucine moths may be released from insects which have been subjected to quite drastic surgical procedures1, but they have never been observed in decapitated preparations2. An attempt has now been made to investigate the role of the brain in mediating this response and in determining its quantitative strength, using the techniques of pupal surgery described by Williams3. One hundred female pupae of Automeris cinerea were chilled at 6°C. for eight weeks immediately following their reception from Argentina, and were then transferred daily (at 25° C.) in batches of five in order to break diapause. On the fifth to eighth day after transfer, they were chilled at 4° C. for 1 hr., anaesthetized in carbon dioxide for 30 min. while packed round with melting ice, and subjected to gross brain surgery through a window cut in the facial cuticle. After surgery, the pupae were sealed with the usual precautions3 and returned to 25°C. The yield in terms of histologically acceptable lesions was approximately 50 per cent. The surgical procedures, which were previously rehearsed on the large Indian Antherea mylitta, are summarized in Fig. 1. It may be noted that while procedure 1 results in blind moths the optic glomeruli II and III of which remain intact, procedure 2 ablates the entire optic complex, while sparing the medial lobes of the protocerebrum. Procedure 5 permits the development of a recognizable subœsophageal unit in isolation; while the resulting neuropil shows evidence of condensation, the normal features of its intrinsic organization may readily be recognized in favourably oriented sections, and moths so treated differ characteristically in their behaviour from those from which the subœsophageal ganglion has been extirpated.

PREVIOUS publications have described the relation between precurrent flight performance and the strength of a subsequent rhythmic settling response (‘rocking’) in the neotropical saturniid moth Automeris aurantiaca Weymer (Hemileucinae1)2. The strength of the rocking response, measured as the number of complete oscillations of the rhythm, increases linearly with duration of flight, and in the absence of further flight responses is stable to retesting for periods of at least 90 min. The mechanism by which flight performance is thus registered and expressed in the subsequent settling behaviour is of particular interest, for the relationship is similar to that between the flight activity of foraging honey-bees, and the rhythmic distance-specific components of the communication dance2

MOTHS of the neotropical Saturnioid family Hemileucidae perform a special movement on assuming the resting position from any preceding activity, which has been termed ‘rocking’1. It is rigidly co-ordinated, and consists of fast, rhythmic side-to-side oscillations of the entire animal. This movement is unique to the Hemileucidae, and appears to be a highly conservative character within that family, for it occurs in all species so far examined, irrespective of either size or mode of protective coloration2. Its function, if any, is unknown, but it is not concerned with the sexual responses of either sex, nor do the moths possess any known non-sexual social behaviour. The strength of this response may be scored as the number of complete oscillations performed; an analysis has shown that the strength of rocking executed by unconstrained moths of the Brazilian species Automeris aurantiaca Weym. is related to the nature of the sequence of acts preceding it1.