A new nematode species, Comephoronema multipapillatum sp. n. (Cystidicolidae), is described from the anterior intestine and caecum of the squirrelfish Holocentrus adscensionis (Osbeck) (Beryciformes: Holocentridae) collected in Angra dos Reis, State of Rio de Janeiro, offshore Brazil. The new species was placed in Comephoronema Layman, 1933 by having an oval oral aperture, four submedian labia, four bilobed submedian sublabia, two narrow lateral pseudolabia and four single cephalic papillae, but mainly by numerous precloacal papillae in males (more than six pairs), in which it differs from species of the otherwise morphologically similar genus Ascarophis van Beneden, 1871. Comephoronema multipapillatum sp. n. can be easily distinguished from other congeners based on the high number of precloacal papillae in males (18 pairs + one unpaired) and also by the bidentate plate structure on the inner margin of pseudolabia, mature eggs with two long filaments on a single pole, body length of male (9.4-11.5 mm) and female (10.2-19.9 mm), left spicule size (222-278 µm) and length ratio of spicules (1 : 2.2-2.8). This is the fifth nominal species of Comephoronema, the first nematode registered parasitizing H. adscensionis and the first species of the genus in the Neotropical part of the Atlantic Ocean.
A new species of the cyclopoid copepod genus Ergasilus von Nordmann, 1832 is described based on adult female specimens removed from the gills of the yellow snapper Lutjanus argentiventris (Peters) and the yellowfin snook Centropomus robalito Jordan et Gilbert from a Pacific coastal system of Mexico. The new species Ergasilus davidi sp. n. has a combination of characters that includes a two-segmented first leg endopod, a three-segmented fourth leg endopod, and the presence of a single seta on the first antennular segment. These characters are shared with 14 other congeners known mainly from Brazil and North America. It differs from these other species in the armature and ornamentation of legs 1 and 4, the shape of the body, and the structure and ornamentation of the antennae. Additional characters include a maxillar basis armed with blunt teeth, distally bent maxillular setae, and naked margins of first exopodal segments of legs 2-4. Previous regional records of Ergasilus sp. from both fish species are probably assignable to E. davidi. The prevalence and intensity of infection was estimated for both teleost species and agrees to previous data. Based on other records of the genus from several other teleost species in the surveyed area and adjacent zones of the Eastern Pacific, it is presumed that the new species could have a wider range of hosts. The new species represents the first Ergasilus described from Mexican waters of the Pacific. Overall, the genus remains poorly known in Central America and Mexico.
Fianoniella stenognatha sp. n. from the Columbretes Islands (Castellón, Spain) is described and illustrated. The new species is distinguished by its longer and narrower mandibles with parallel or divergent rims in the apical half, wider clypeus, hind ocelli more separated and closer to the eyes, and longer flagellar segments. Additional notes to complete the original description of the closest species, F. laeviscutum (Horstmann), are given. A key to the European species of Fianoniella is provided.
A new species of Chondracanthidae (Copepoda: Cyclopoida), Heterochondria orientalis sp. n., is described based on specimens of both sexes collected from the gill rakers and the inner side of the operculum of the many-banded sole, Zebrias fasciatus (Basilewsky), from the Yellow Sea, Korea. The new species resembles most closely H. zebriae (Ho, Kim et Kuman, 2000), but can be distinguished from this species and other congeners by the shape of the trunk and length of the antenna, the number of teeth on the mandible and the terminal process of the maxilla, and the structure of the male antennule and maxilliped. Heterochondria orientalis is the first copepod species reported from Z. fasciatus and the first heterochondrid species reported from sole fishes in the Northwest Pacific. A key to distinguish all 10 nominal species of the genus is provided.
Lernanthropus cynoscicola sp.n. (Copepoda: Lernanthropidae), a parasite of sciaenid fish Cynoscion striatus Cuvier from the coast of Argentina, is described and illustrated. The new species resembles five other species of Lernanthropus in general body shape, but it can be distinguished from them by the relatively short and tapered dorsal plate of the 4th leg-bearing segment, the length of the 4th legs being approximately equal to the rest of the body, and other differences. L. trachuri Brian, 1903 is reported for the first time in Argentina on Trachurus lathami from the coast of the Buenos Aires province.
The onchocercid filaria Litomosoides taylori sp. n. is described from the sigmodontine cricetid Nectomys palmipes Allen et Chapman in northeast Venezuela. A voucher specimen of the new species was used for molecular analysis of the coxI and 12S rDNA genes, and screened for the presence of the endobacterium Wolbachia pipientis. Litomosoides taylori belongs to the ''sigmodontis group'' of Litomosoides and a combination of characters can be used to distinguish it from the remaining 18 species forming this group. Among the five Nectomys species, all living near running water, N. squamipes also harbours Litomosoides species, L. khonae in Brazil and L. navonae in Argentina. These three Litomosoides species of the ''sigmodontis group'' do not share any particular characters. Gene sequences of L. taylori differ from those of the five Litomosoides species available, the three of the ''carinii group'' being the most distant. The new species harbours W. pipientis, which is concurrent with the great majority of Litomosoides species screened to date.
Mymarothecium boegeri sp. n. (Monogenea: Dactylogyridae) is described from the gills of Colossoma macropomum Cuvier (Characidae), collected from the aquaria of the ''Centro de Pesquisas em Aquicultura, Departamento Nacional de Obras Contra as Secas (DNOCS)'', Pentecoste City, State of Ceará, Brazil. Mymarothecium viatorum Boeger, Piasecki et Sobecka, 2002 is reported from the type host, Piaractus brachypomus (Cuvier) (Characidae) and from a new host, P. mesopotamicus (Holmberg) (Characidae), confirming the occurrence of M. viatorum in the Neotropical Region. The new species differs from the congeneric species in the structure of male copulatory complex; it is more closely related to M. viatorum by the presence of a posteromedial projection on ventral bar.
The sicklefin redhorse, Moxostoma sp. (Cypriniformes: Catostomidae), is an innominate imperiled catostomid endemic to the Hiwassee and Little Tennessee river basins, which has been restricted to a few tributaries of these systems by impoundments. During collections to propagate sicklefin redhorse for reintroduction, a myxozoan, described herein, was observed infecting sicklefin redhorse in the Little Tennessee River Basin, North Carolina. Myxobolus naylori Ksepka et Bullard sp. n. infects the stratum spongiosum covering the scales of sicklefin redhorse. Myxospores of the new species differ from all congeners by the combination of having a mucous envelope, intercapsular process, and sutural markings as well as lacking an iodinophilic vacuole in the sporoplasm. and A phylogenetic analysis of the 18S rDNA gene recovered the new species in a polytomy with Myxobolus marumotoi Li et Sato, 2014 and a clade comprised of species of Myxobolus Bütschli, 1882; Thelohanellus Kudo, 1933, and Dicauda Hoffman et Walker, 1973. Histological sections of infected sicklefin redhorse skin revealed myxospores within a plasmodium in the stratum spongiosum dorsal to scales, encapsulated in collagen fibres, and associated with focal erosion of scales directly beneath the plasmodium; in some instances, the scale was perforated by the plasmodium. The specificity of the new species to sicklefin redhorse may make it a useful biological tag to differentiate sicklefin redhorse from morphologically similar species. The new species is the first parasite reported from sicklefin redhorse, a species of concern to the United States Fish and Wildlife Service. No species of Myxobolus has been reported from species of Moxostoma in the Southeast United States. As it was observed that Myxobolus minutus Rosser, Griffin, Quiniou, Alberson, Woodyard, Mischker, Greenway, Wise et Pote, 2016 is a primary junior homonym of Myxobolus minutus Nemeczek, 1911, we propose the replacement name Myxobolus diminutus (Rosser, Griffin, Quiniou, Alberson, Woodyard, Mischker, Greenway, Wise et Pote, 2016).
A new nematode species (Neoascarophis mariae n. sp.) is described based on specimens collected from the Argentine goatfish Mullus argentinae (Hubbs et Marini) from coastal waters off the state of Rio de Janeiro, Brazil. In the genus, the new species belongs to the group of species with females that have the vulva near the posterior end of the body. Only males of Neoascarophis longispicula Moravec et Klimpel, 2009 are known and can be distinguished from those of the new species by their larger body, developed and somewhat dorsoventrally expanded flat inner part of the pseudolabia, bifurcate deirids and larger spicules (the left one with a rounded tip) with a different length ratio. Other species with females that have the vulva near the equatorial region are N. yarihige Machida, 1976 and N. bathygadi Machida, 1976. Both males and females of N. yarihige are longer than those of the new species and have a shorter vestibule; males have shorter spicules with a different length ratio. Neoascarophis bathygadi is the only member of the genus that shares the presence of a cephalic vesicle with the new species, which, however, is shorter and arises at 40 µm from the anterior end instead from the deirids, as in the new species. Both males and females of N. bathygadi are also longer than those of the new species and have a shorter vestibule; males have a larger left spicule, but shorter right spicule and a different length ratio. Ascarophis upeneichthys Johnston et Mawson, 1945, a parasite of a mullid host, is transferred to Neoascarophis Machida, 1976 and is distinguished from the new species by having a shorter vestibule in females and shorter spicules (left spicule with a pointed tip) with a different length ratio in males.
Nothobomolochus cresseyi sp. n. (Copepoda: Bomolochidae), a parasite from gills of the engraulid fish Engraulis anchoita Hubbs et Marini (Pisces: Engraulidae) from the coast of Argentina, is described and illustrated. The new species can be distinguished from other species of Nothobomolochus Vervoort, 1962 by the following combination of characters: three modified setae on the base of the antennule similar in length to the plumose setae, the nature of the armature of the third segment of the fourth endopod and the length and width of the thoracic somites 2 to 4 decreasing gradually. The new species represents the first record of this genus for Argentina.