3.2 Pathogen identification
The moribund sea urchins exhibited symptoms of the “bald sea urchin disease” described by Clemente et al. (2014) (Figure 2b) (Tamura et al. 2011). Species identification was based on sequence homology analysis by comparing the available Paramoeba sequences in the Genbank database. No bacterial growth was observed, and all of the infected sea urchins were only positive for Paramoeba branquiphila . Despite the detection of this paramoeba, one must be cautious about concluding that the cause of the disease is the amoeba. Additional experiments using Koch’s postulate need to be performed.