ABSTRACT
This study aims to verify the relevance of Brachidontes pharaonis to assess the ecotoxicological status of polluted sites. For this, the levels of some heavy metals (i.e. Zn, Cu, Pb, and Cd) and a battery of biomarkers including metallothionein (MT), malondialdehyde (MDA), reduced glutathione (GSH), glutathione peroxidase (GPx), superoxide dismutase (SOD), and catalase (CAT) were assessed in mussels collected from the harbor of Rades (North), and the harbor of Zarzis (South). Moreover, abiotic parameters including temperature, salinity, pH, and dissolved oxygen were assessed. Results from the ICP-OES showed that the southern population exhibited a higher metal pollution index with significantly higher Zn, Cu, and Pb concentrations. Moreover, the specimens from Zarzis displayed significantly higher levels of MDA, MT, GSH, GPx, SOD, and CAT reflecting higher levels of oxidative and chemical stress. These results emphasize the potential utility of B. pharaonis for the monitoring of heavily impacted sites.
Subject(s)
Bivalvia , Metals, Heavy , Mytilidae , Water Pollutants, Chemical , Animals , Environmental Biomarkers , Bioaccumulation , Lead , Metals, Heavy/toxicity , Metals, Heavy/analysis , Bivalvia/metabolism , Oxidative Stress , Catalase/metabolism , Metallothionein/metabolism , Glutathione Peroxidase/metabolism , Superoxide Dismutase/metabolism , Biomarkers/metabolism , Water Pollutants, Chemical/toxicity , Water Pollutants, Chemical/analysisABSTRACT
The family Flabelligeridae was previously represented in Tunisia by four genera including four species: Bradabyssa villosa (Rathke, 1843), Therochaeta flabellata (M. Sars in G.O. Sars, 1872), Pherusa plumosa (Müller, 1776), and Piromis eruca (Claparède, 1869). In this paper we report a fifth genus, Trophoniella, for the first time in Tunisia. The specimens were collected in Radés Station, Gulf of Tunis (Central Mediterranean) and belong to a new species, namely Trophoniella radesiensis n. sp., which is characterized by having: (1) a very smooth tunic, body covered dorsally, ventrally, and laterally by sediment grains (except in the posterior region), and (2) well-developed parapodia showing short neurohooks from chaetiger 6 to 19 and anchylosed neurohooks from chaetiger 20. Based on the 16S, the new species belongs to a low supported Piromis/Trophoniella clade and shows a 16.1% of genetic distance from Trophoniella hephaistos Jimi Fujiwara, 2016, the single known species of the genus sequenced to date. [Zoobank lsid: urn:lsid:zoobank.org:act:D7C85C70-87FF-4AF4-8599-A8462B3FB8B1].
