Kudoa ajurutellus

Host: Aspistor quadriscutis (Siluriformes: Ariidae).

. The sequence of the Small Subunit of the ribosomal RNA (18 S rDNA) was deposited in GenBank (Access number: MK 089553). ZooBank number for species: urna: lsid: zoobank. org: act: A 1 A 893 F 0 - 0 B 46 - 48 D 0 - 9882 - 671 B 7 A 82580 F.

Infection site: Pseudocysts in skeletal muscle. Prevalence: 77.6 % (44 % for males and 33.6 % for females).

was observed in live fish and no evidence of myoliquefaction was observed. The staining of the histological sections revealed no inflammatory response to Pseudocysts found in the musculature of the hosts (Fig. 3 A). Some discreet disorganization was also observed in the myofibrils of the musculature at the sites where the pseudocysts were observed (Fig. 3 B). Molecular Analysis. A partial sequence of 908 base pairs of the 18 S rDNA gene was obtained from the spores of Kudoa ajurutellus n. sp. recovered from the skeletal musculature of A. quadriscutis. This sequence was deposited in GenBank under access number MK 089553. The phylogenetic analysis generated a tree with a single large clade, denominated A, containing the Kudoa species, with an outgroup consisting of Gastromyxum rafii Freeman & Kristmundsson 2015 and Gastromyxum bulani Freeman & Kristmundsson 2015. Clade A was divided into two subclades, A 1 and A 2. Kudoa ajurutellus n. sp. was allocated to clade A 1, which was formed by Kudoa species that parasitise marine fish hosts. The clustering of subclade A 1 was related primarily to the tissue tropism of the host (Fig. 4), with Kudoa ajurutellus n. sp. parasitising the musculature of the marine fish, A. quadriscutis. The other species of clade A 1 parasitise the muscle, brain, intestine, esophagus, ovary, heart and systemic infection of their hosts. Kudoa ajurutellus n. sp. is phylogenetically closest to K. lethrini (Burger, Cribb & Adlard 2007) and K. neurophila (Grossel et al. 2005), which both parasitise the brain, respectively, of Gymnocranius audleyi and Latris lineata. Kudoa ajurutellus n. sp. was the basal taxon of clade A 1. Subclade A 2 is formed by Kudoa spp. parasites of the muscle and heart. The optimal evolutionary models for the maximum likelihood (ML) and Bayesian analyses were determined by W-IQ-TREE (Trifinopoulos et al. 2016) which identified the best evolutionary model as the general time reversible model (GTR + F + I). Nucleotide frequencies were estimated (A = 0.2865, C = 0.1826, G = 0.2547, T = 0.2762) and six rates of nucleotide substitution were calculated, with AC = 1.1603, AG = 3.6633, AT = 2.3450, CG = 0.6466, CT = 6.5433, GT = 1.00000. The proportion of invariable sites was 0.4451 and the alpha value of the gamma distribution parameter was 0.4865. This smallest P distance between Kudoa ajurutellus n. sp. and other Kudoa species was 4.43 % (Table 2). Kudoa ajurutellus n. sp. has the following taxonomic classification Phylum Cnidaria Hatschek, 1888 Subphylum Myxozoa Grasse, 1970 Class Myxosporea Butschli, 1881 Order Multivalvulida Shulman, 1959 Family Kudoidae Meglitsch, 1960 Genus Kudoa Meglitsch, 1947 Species Kudoa ajurutellus n. sp

Locality: Ajuruteua beach in the municipality of Bragança, in the northeastern extreme of the state of Pará, Brazil.

Etymology: The specific name ajurutellus refers to the name of a fruit (Ajuru), which is very common at the type locality, Ajuruteua, in the municipality of Bragança in the state of Pará, Brazil. The name of the locality is also derived from the fruit.

Deposit of the type specimen: Histological sections of Kudoa ajurutellus n. sp. stained with ZN (ziehl-neelsen)