An evaluation of Allonais inaequalis Stephenson, 1911 (Oligochaeta: Naididae) as a toxicity test organism

Abstract

Oligochaeta are suitable for assessing the effects of contaminants on the environment, but in Brazil, few studies have been developed for the use of native species in toxicity bioassays. Given the increasing interest in this research area by the environmental agencies for the usage of species of aquatic Oligochaeta in ecotoxicological studies, in addition to the need for greater biological knowledge of native species, the present work aimed to establish a protocol to be used in ecotoxicological bioassays using the native species Allonais inaequalis. The Naididae A. inaequalis (Stephenson, 1911) was first described as Nais pectinata var. inaequalis Stephenson, 1911. The distribution of this species has been mentioned for several environments in Brazil. This paper presents results from tests on the sensitivity of the species to KCl (LC50) and to zinc chloride (LC50), the general characteristics of the species and laboratory breeding methods. Laboratory rearing, the collection and identification of the organism are easy when compared to other organisms such as Chironomus xanthus, a species commonly used in toxicity bioassays. It is expected that this work will assist in the use of A. inaequalis species for routine water monitoring protocols for tropical environments.