Reproductive pattern of the neotropical terrestrial isopod Benthana cairensis (Isopoda: Philosciidae)

Abstract

Population studies on terrestrial isopods, particularly those examining temperate and certain tropical species, are often performed through an investigation of life history traits, such as size at sexual maturity, fecundity and life span. In this study, some of the life history traits of Benthana cairensis Sokolowicz, Araujo, and Boelter, 2008, a neotropical species, were evaluated and tested against the hypothesis that this species has an iteroparous mode of reproduction, with females' reproduction occurring year-round. Samples were collected over an 18-month period from a small area in southern Brazil. Reproduction of B. cairensis peaked in the spring, females' mean fecundity was 10.4 ± 2.73 eggs (Mean ± SD) and mean reproductive allocation was 17% ± 4.08 (Mean ± SD). Females attain sexual maturity when they are approximately five months old and live over one and a half year. Males grow faster, reach smaller sizes and live approximately 13 months. We determined that a female only reproduces for one season, although it is capable of having more than one brood during this season; this result confirms that B. cairensis exhibits an iteroparous mode of reproduction and that reproduction is concentrated in the warmer months. © The Crustacean Society, 2013. Published by Brill NV, Leiden.