Identification ofas the current world's deepest trematode.

Abstract

The deepest recorded depth for trematodes currently stands at approximately 6200 m. This depth record was achieved solely through sequence datasets ofsp. obtained from a gastropod. Given that trematodes of this genus typically use fish as definitive hosts, the origin of the trematode sequence was thought to be larval stages. However, the specific species remained unclear owing to the absence of reported adult-stage sequences. In the present study, we definitively identified the deepest trematode asby comparing 28S ribosomal DNA sequences from adult worms from the macrourid fishwith data from the gastropod in the previous study.