Characterising parasitie gnathiid isopod species and matching life stages with ribosomal DNA ITS2 sequences

Abstract

Gnathiid isopods were collected from Heron and Lizard Islands, Great Barrier Reef, Australia. The presence of three species was inferred using ribosomal DNA internal transcribed spacer 2 (ITS2) sequences from both adult and juvenile stages. Having matched DNA sequences from all stages of one of the species' life cycles, we can now identify those individuals based purely on their morphology. The level of variation between species ranged from 38.5 to 43% compared to within-species variation levels of <1%.