Caracterização do padrão atividade-repouso em Omophoita Octoguttata (Coleoptera, Chrysomelidae)

Abstract

Biological rhythms are ubiquitous to living beings, however, different animals may vary in the expression of their rhythms. Characterizing the activity-rest rhythm is important to know the biology and ecology of an animal, as well as to identify time niches. With the need to identify different resting activity patterns, studies with invertebrates such as Nematoda, Mollusca, Arachnida and some groups of insects have been known, where a sleep-like resting state has been shown. Thus, in this study Omophoita octoguttata (Fabricius, 1775) (Coleoptera, Chrysomelidae) was used as a model to investigate the activity/rest pattern. For this, seven individuals of O. octoguttata (manually collected) were used and kept in a BOD camera and filmed individually for 48 consecutive hours in a 12h light/dark pattern. Activity was assessed every hour for a period of 15 minutes. For this, a motion capture software was used where it was possible to trace the movements presented by these insects, after which the COSINOR method was used to verify the presence of a circadian rhythmicity and determination of the rhythmic parameters. Omophoita octoguttata presented an activity/rest rhythm expression period of 23.9h (F = 10.491 p = 0.0001) with a maximum activity point (acrophase) at 10:38 am. These values indicate the synchronization of these animals to the 24h light-dark cycle. The characterization of the activity/rest pattern in O. octoguttata is a very relevant study for the enrichment of information about this species and the order to which it belongs. Complementary analysis in free course protocol may determine the endogenous expression of the rhythm, as well as its endogenous period.