We provide a summary overview of the diversity of trematode parasites in freshwater fishes of the 'New World', i.e. the Americas, with emphasis on adult forms. The trematode fauna of three regions, South America, Middle America, and USA and Canada (North America north of Mexico), are considered separately. In total, 462 trematode species have been reported as adults from the Americas. The proportion of host species examined for parasites varies widely across the Americas, from a high of 45% in the Mexican region of Middle America to less than 5% in South America. North and South America share no adult species, and one exclusively freshwater genus, Creptotrema Travassos, Artigas & Pereira, 1928 in the Allocreadiidae Looss, 1902 is the most widely distributed. Metacercariae of strigeiforms maturing in fish-eating birds (e.g. species of the Diplostomidae Poirier, 1886) are common and widely distributed. The review also highlights the paucity of known life-cycles. The foreseeable future of diversity studies belongs to integrative approaches and the application of molecular ecological methods. While opportunistic sampling will remain important in describing and cataloguing the trematode fauna, a better understanding of trematode diversity and biology will also depend on strategic sampling throughout the Americas.

/pdf/trematode-diversity-in-freshwater-fishes-of-the-globe-ii-new-16ttlnhqe8.pdf

Trematode diversity in freshwater fishes of the Globe II: 'New World'

Trematodes of the family Orientocreadiidae are mostly parasites of freshwater fishes. Here, the phylogenetic position of this family is inferred based on the partial 28S rDNA sequence from a representative of the genus Orientocreadium s. str.–О. pseudobagri Yamaguti, 1934. Sequences were analysed by maximum likelihood and Bayesian inference algorithms. Both approaches placed the Orientocreadiidae within a clade corresponding to the superfamily Plagiorchioidea and supported the family Leptophallidae as a sister taxon.

Phylogenetic position of the family Orientocreadiidae within the superfamily Plagiorchioidea (Trematoda) based on partial 28S rDNA sequence.

Resolving evolutionary changes in parasite life cycle complexity: Molecular phylogeny of the trematode genus Alloglossidium indicates more than one origin of precociousness.

The systematic position of two genera of Macroderoididae McMullen, 1937, Perezitrema Barus & Moravec, 1967 and Magnivitellinum Kloss, 1966 is reviewed based on a phylogenetic analysis of the interrelationships of 15 species of the family allocated into six genera, along with 44 species of plagiorchioid trematodes, using partial sequences of the 28S rRNA gene. Sequences were analysed through parsimony, maximum likelihood and Bayesian inference. The obtained topologies show Perezitrema as the sister taxon of three species of Macroderoides Pearse, 1924; the latter genus appears to be paraphyletic since another three species are not included in this group. Instead, Magnivitellinum was placed as the sister taxon of Alloglossidium Simer, 1929. These relationships are well supported by high bootstrap and posterior probability values. The resulting trees demonstrate that the family Macroderoididae, as currently conceived in taxonomic treatments, is not monophyletic. Magnivitellinum simplex Kloss, 1966 and Alloglossidium spp. were nested as sister taxa of members of the family Leptophallidae Dayal, 1938, whereas Perezitrema bychowskii Barus & Moravec, 1967 and species of Macroderoides and Paramacroderoides Venard, 1941 were grouped with Auridistomum chelydrae (Stafford, 1900), a monotypic member of Auridistomidae Stunkard, 1924. Based on our results, a new family, Alloglossidiidae n. fam. was established to accommodate the genera Magnivitellinum and Alloglossidium.

Phylogenetic position of Magnivitellinum Kloss, 1966 and Perezitrema Baruš & Moravec, 1967 (Trematoda: Plagiorchioidea: Macroderoididae) inferred from partial 28S rDNA sequences, with the establishment of Alloglossidiidae n. fam.

/pdf/miscellaneous-fish-helminth-parasite-trematoda-cestoidea-519n6o5klv.pdf

Miscellaneous Fish Helminth Parasite (Trematoda, Cestoidea, Nematoda, Acanthocephala) Records from Arkansas

A new species of Alloglossidium is described from the intestines of 2 madtom species (Noturus leptacanthus and Noturus gyrinus) that were collected from the run of a small, unnamed spring system that drains into the Santa Fe River, Florida. Alloglossidium floridense n. sp. is morphologically very similar to other nonprecocious Alloglossidium spp. that use ictalurids as definitive hosts, but can be distinguished by a combination of its smaller overall size (length and width), large eggs in relation to its small body size, position of the vitellaria, ovary shape, and position of the ovary in relation to the cirrus sac. A comparison of nuclear rDNA sequences (spanning partial 18s, complete ITS1, 5.8s, ITS2, and partial 28s regions) showed that A. floridense n. sp. diverged by 0.70–3.17% from the other 4, nonprecocious species that infect ictalurids (Alloglossidium corti, Alloglossidium fonti, Alloglossidium geminum, and Alloglossidium kenti). The new species of Alloglossidium, described herein, is...

Thomas J. Fayton

Papers

Alloglossidium floridense n. sp. (Digenea: Macroderoididae) from a Spring Run in North Central Florida