Relatedness of novel species of Myxidium Bütschli, 1882, Zschokkella Auerbach, 1910 and Ellipsomyxa Køie, 2003 (Myxosporea: Bivalvulida) from the gall bladders of marine fishes (Teleostei) from Australian waters

Abstract

During a parasitological survey, Myxidium-like spores were identified in the gall bladders of marine fishes from Australian waters. This paper describes four novel species of Ellipsomyxa Køie, 2003, three novel species of Myxidium Bütschli, 1882 and six novel species of Zschokkella Auerbach, 1910 from teleosts from Australian waters using a combination of morphological, biological and molecular characters. Phylogenetic analyses showed a monophyletic relationship of all Ellipsomyxa spp. sequences with Sigmomyxa sphaerica (Thélohan, 1895) and Myxidium queenslandicus Gunter & Adlard, 2008 as sister species to the clade. The validity of genus Sigmomyxa Karlsbakk & Køie, 2012 is discussed. In phylogenetic analyses, the novel species of Myxidium fell within the 'marine' clade of Fiala (2006). However, the novel species of Zschokkella fell within the 'freshwater' clade of Fiala (2006) and formed a distinct clade with all other sequences of Zschokkella spp. from the gall bladder of marine fish and a sequence of a species of Myxobolus Bütschli 1882, also from the gall bladder of a marine fish. This is the second distinct marine lineage to emerge within the freshwater clade.