First characterization of the behavioral repertory in a ricinulid: Cryptocellus narino Platnick & Paz 1979 (Arachnida, Ricinulei, Ricinoididae)

Abstract

Ricinuleids are considered one of the most enigmatic and neglected arachnid orders. The low diversity and poor local abundance of several species, makes the study of most aspects related to biology and behavior of this group very difficult. Most of the current knowledge related to ricinuleid biology relies on anecdotal observations. So far, no published studies exist that describe in detail ricinuleid behavior. Here we present the behavioral repertory of a ricinuleid, the Neotropical species Cryptocellus narino. Eighteen individuals (six males, six females and six immatures) were examined under laboratory conditions to describe and quantify their behavioral repertory and its variation along the day. The behavioral repertory in males exhibited a higher number of behavioral acts when compared to females and immatures. The most frequent behavioral categories were “resting”, “exploring” and “feeding”. “Resting” was the most common behavior during the photophase, while “feeding” and “exploring” were the most common during scotophase, suggesting this species is predominantly nocturnal. This study also provides behaviors previously not known for this group as well as a description of the daily schedule. We expect this work will become a baseline study for further research on ricinuleid ethology.