A new species of Myxobolus (Myxozoa: Bivalvulida) infecting the medulla oblongata and nerve cord of brook trout Salvelinus fontinalis in southern Appalachia (New River, NC, USA)

First report of Myxobolus neurofontinalis (Bivalvulida: Myxobolidae) infecting anadromous Brook Trout from Prince Edward Island, Canada

“…Polar capsules were 7.0-9.0 μm (8.2 ± 0.7 μm; N = 80) long and 3.0-4.0 μm (3.1 ± 0.4 μm; N = 80) wide, with 7-10 polar tubule coils (Figure 1). Like the specimens of M. neurofontinalis from North Carolina (Ksepka et al 2019), an intercapsular process, iodinophilic vacuole in the sporoplasm, mucous envelope on the rounded posterior margin of the myxospore, and sutural markings were likewise present in the collected samples (Figure 1).…”

“…of NBF-fixed myxospores sourced from the central nervous system of Brook Trout from PEI were indistinguishable from those of NBF-fixed myxospores of M. neurofontinalis, suggesting that the samples collected herein are conspecific with M. neurofontinalis (see Ksepka et al 2019). The myxospores from PEI Brook Trout were 13.0-15.0 μm (mean ± SD = 14.2 ± 0.6 μm; N = 50) long, 9.0-11.0 μm (10.4 ± 0.7 μm; N = 40) wide, and 8.0-10.0 μm (8.5 ± 0.7 μm; N = 10) thick (Figure 1).…”

“…Myxobolus fryeri infects Coho Salmon in Oregon (Ferguson et al 2008). Myxobolus neurofontinalis infects Brook Trout Salvelinus fontinalis Mitchill 1814 in the New River basin, North Carolina (Ksepka et al 2019). Salmonid central nervous system-infecting species are not typically pathogenic or immunogenic.…”

“…After extraction, the concentration was measured using a NanoDrop 1000 spectrophotometer (Thermo Scientific, NanoDrop Technologies) and the sample was stored at −20°C. A fragment of a variable region of the SSU rDNA was amplified using primers M153-F (5′-CATTG GAT AAC CGT GGG AAATCT-3′) and M1480-R (5′-GTGGT GCC CTT CCG TCA ATTCC-3′; Ksepka et al 2019). Polymerase chain reaction (PCR) amplification followed Ksepka et al (2019).…”

“…A fragment of a variable region of the SSU rDNA was amplified using primers M153-F (5′-CATTG GAT AAC CGT GGG AAATCT-3′) and M1480-R (5′-GTGGT GCC CTT CCG TCA ATTCC-3′; Ksepka et al 2019). Polymerase chain reaction (PCR) amplification followed Ksepka et al (2019). The PCR products were visualized on a 1% agarose gel and purified using the QIAquick PCR Purification Kit (Qiagen) following the manufacturer's protocol, with the exception that sterile water was substituted for AE buffer for eluting DNA.…”