Gyrodactylus crysoleucas

Rahmouni, Chahrazed, Seifertová, Mária, Bean, Megan G. & Šimková, Andrea, 2024, Intraspecific variation in Gyrodactylus mediotorus and G. crysoleucas (Gyrodactylidae) from Nearctic shiners (Leuciscidae): evidence for ongoing speciation, host-switching, and parasite translocation, Parasite (Paris, France) 31 (29), pp. 1-14 : 7

Gyrodactylus crysoleucas

Two fragments, the first covering the 18S rDNA (442 bp) and the second covering the ITS regions (1,207 bp), were successfully sequenced for two gyrodactylid specimens from Texas, and the newly obtained sequences were found to be identical. nBLAST search indicated G. crysoleucas KT 149283 [ 55] from the farmed golden shiner N. crysoleucas in Minnesota ( USA) as an identical match to our specimens according to sequences of 18S rDNA (100% similarity, 100% coverage), while G. crysoleucas KT 149287 [ 55] was recovered as the closest match to the specimens studied herein according to the sequences of the ITS regions (99.17% similarity, 99% coverage, p -distance = 0.3%; 3 bp). In accordance with the morphological identification, our specimens were genetically assigned to G. crysoleucas following the delimitation by Ziȩtara and Lumme [ 112] and the recent findings of Rahmouni et al. [ 82]. Sequences of 18S rDNA further indicated Gyrodactylus salmonis (Yin and Sproston, 1948) from the non-native rainbow trout Oncorhynchus mykiss (Walbaum, 1792) from Veracruz ( Mexico) (JN230350, [ 92]) and Washington ( USA) (JF836097, [ 33]) as the closest match to our G. crysoleucas specimens from Texas (for both G. salmonis genetic variants; 99.55% similarity, 100% coverage, p -distance = 0.5%; 2 bp). Phylogenetically, G. crysoleucas parasitizing herein C. venusta from Texas together with its congener parasitizing N. crysoleucas from Minnesota formed a highly supported basal clade ( PP = 1, BS = 100) in relation to a large clade of Nearctic Gyrodactylus spp. ( Figure 3 ).

Figures

Figure 3. Bayesian inference (BI) phylogram of Gyrodactylus spp. parasitizing Nearctic Cypriniformes based on sequences of the ITS regions (927 bp). Values above branches indicate posterior probabilities (PP) from BI analyses and bootstrap support (BS) from ML. Values below 0.80 (BI) and 70 (ML) are shown as dashes.