Stemmatostoma cribbi n. sp. (Digenea: Cryptogonimidae) from Freshwater Fishes in the Wet Tropics Bioregion of Queensland, Australia.

Abstract

A survey of the parasite fauna of freshwater fishes from the Wet Tropics Bioregion in Queensland, Australia, revealed the presence of a new species of Stemmatostoma Cribb, 1986 (Digenea: Cryptogonimidae). Stemmatostoma cribbi n. sp. is described from the intestine and pyloric caeca of 2 species of grunter (Terapontidae), Hephaestus fuliginosus (Macleay) and Hephaestus tulliensis (De Vis), and the Jungle perch (Kuhliidae), Kuhlia rupestris (Lacepède), collected from the Barron and Mulgrave-Russell River drainage divisions in tropical north Queensland, Australia. Stemmatostoma cribbi is primarily distinguished morphologically from the type and only other species in the genus, Stemmatostoma pearsoni Cribb, 1986, in having consistently fewer oral spines (14 in S. cribbi vs. 16 in S. pearsoni). Alignment of novel molecular data for S. cribbi and S. pearsoni revealed that they differ genetically by 26 nucleotides (2.1%) over the 1,258 bp partial large subunit (LSU) region, 1 nucleotide (0.8%) over the 121 bp partial 5.8S region, and 23 nucleotides (7.2%) over the entire 318 bp ITS2 rDNA region. Bayesian inference and maximum likelihood phylogenetic analyses of the partial LSU region for the species of Stemmatostoma sequenced here were used to explore the relationships of these species to other cryptogonimid species reported from freshwater ecosystems.