North American crayfish harbour diverse members of the Nudiviridae

Three novel crayfish-infecting nudiviruses from crayfish in North America represent the first genomic confirmation of nudiviruses in crayfish: Faxonius propinquus nudivirus (FpNV), Faxonius rusticus nudivirus (FrNV),
and Faxonius virilis nudivirus (FvNV). Histopathology and electron microscopy revealed nuclear infections,
including nuclear hypertrophy in hepatopancreatic epithelial cells and the presence of membrane-bound bacilliform virions. Metagenomic sequencing resulted in complete circular genome assembly, and phylogenetic analyses (based on nudivirus core genes) placed these viruses within the unofficial Epsilonnudivirus genus. One of
the nudiviruses was detected in the antennal gland of its host, and another is correlated with invasive crayfish
decline in one infected lake ecosystem - suggesting a potential route for viral transmission through water, and
possible population level impact. This study highlights the importance of genomic and ecological data in
elucidating the diversity and evolutionary relationships of the Nudiviridae, while expanding their known diversity
and range of host species.