Two New Species of Plistophora (Microsporidea) from North American Fish with a Synopsis of Microsporidea of Freshwater and Euryhaline Fishes

SYNOPSIS. Two new species of Microsporidea, Plistophora salmonae from steelhead and rainbow trout (Salmo gairdntri) and Plistophora crpedianar from gizzard shad ( Dorosoma cepedianum) are described. Schizonts to spores of P. cepedianae were found at one time within the same cyst, while only sporonts and spores of P. salmonae were found within the cyst.
An illustrated synopsis of the known Microsporidea of freshwater and euryhaline fishes is given.     

Myxosoma pendula n. sp. (Protozoa,Myxosporida) from the Creek Chub Semotilus atromaculatus*

SYNOPSIS. A new species, Myxosoma pendula, was found surrounded by tissue fluid with granulocytes in pedunculated cysts formed from the mucous membrane of the gill arches of Semotilus atromaculatus collected in the Kewaunee River in Wisconsin. This species has a spherical vegetative stage with 2-layered ectoplasm composed of an outer homogeneous layer and an inner layer with canaliculi, and avoid spores that differentiate in the central area of the endoplasm.     

Myxosoma microspora n. sp. (Myxosporidia: Protozoa) parasitic in the gills of Mugil cephalus L.

A new histozoic species of myxosporidian, Myxosoma microspora n.sp., infecting the gill filaments of Mugil cephalus is described. Cysts measuring 0.5–1.0 mm in diameter were found attached to the gill filaments. Spherical or slightly oval, spores 4.8–5.2 μm in diameter, were present and possessed a thin outer mucous envelope which appeared as small conical protuberances at the ends of the equatorial axis. Polar capsules were pyriform in shape, equal in size and measured 1.6–2.0 × 1.0–1.2 μm; the polar filaments were 22–28 μm in length. There was a bean-shaped sporoplasm measuring 3.5 × 1.5 μm. No iodine vacuole was detected when the parasite was stained with Lugol's iodine.     

Myxidium macrocheili n. sp. (Cnidospora: Myxidiidae) from the Largescale Sucker Catostomus macrocheilus Girard,and a Synopsis of the Myxidium of North American Freshwater Vertebrates*

SYNOPSIS. Myxidium macrocheili n. sp. is described from the gall bladder, bile and pancreatic ducts of Catostomus macrocheilus Girard (largescale sucker) in western Montana. This parasite is markedly host specific; the trophozoite is nonmotile, polysporous, spheroidal, elongated or irregular, often arched and rolled at the edges, and up to 2.5 mm in greatest length; the ecto- and endoplasm are distinct; the sporonts are disporoblastic. The bipolar spore is longitudinally striated, usually ellipsoidal in front view, slightly S-shaped in side view, and averages 11.7 × 6.6 × 6.3 μ; the suture line and ridge are distinct; the polar filaments are coiled 4–6 times. An illustrated synopsis and a key of the 19 species and 10 unnamed forms of Myxidium of North American freshwater vertebrates are presented. At present members of the genus are known to infect fishes, amphibians and a single species of reptile on this continent.     

Sphaeromyxa maiyai sp. n. (Protozoa: Myxosporidea), Coelozoic Parasite of the Pacific Tomcod,Microgadus proxiimus*

SYNOPSIS. Sphaeromyxa maiyai sp. n. (Myxosporidea: Myxiidae) is described from the gall bladder of the Pacific tomcod Microgadus proximus Girard, from Newport, Oregon. The plasmodial stage is discoid averaging between 1 and 2 cm. The spore averages 27.6 × 5.6 μm in breadth, with pyriform polar capsules measuring 9.3 × 3.7 μm. Scanning electron microscopy reveals the presence of numerous longitudinal striations.     

Eimeria aurati n. sp. (Protozoa:Eimeriidae) from Goldfish (Carassius auratus) in North America

SYNOPSIS. Eimeria aurati n. sp. is described from the intestine of the goldfish, Carassius auratus , from Pennsylvania, U.S.A. Oocysts were very numerous in long, whitish, opaque fecal casts. They were 16 to 24 by 14 to 17 μ (mean, 20.1 by 16.3) and were non-sporulated when passed but sporulated 2 to 5 days later.     

Eimeria reedi sp. n. and E. chobotari sp. n. (Protozoa: Eimeriidae) from Heteromyid Rodents

SYNOPSIS The oocysts of 2 new species of Eimeria are described from heteromyid rodents. The subspherical to ellipsoidal cocysts of Eimeria reedi from Perognathus formosus averaged 22.6 by 20.8 μ. An ellipsoidal polar granule was present. The oocyst residuum was a single globule about 8 μ in diameter. The ovoid sporocysts averaged 10.9 by 7.7 μ and had a residuum of 6-12 granules. A Stieda body and substiedal body were present in the sporocysts. Eimeria chobotari oocysts, from Dipodomys merriami and D. microps , were ellipsoidal to ovoid and averaged 47.7 by 35.2 μ. No polar granule was seen. The large oocyst residuum consisted of several granules of various sizes. The ovoid sporocysts averaged 15.8 by 11.3 μ and had a residuum of many small granules. A Stieda body and substiedal body were present in the sporocysts.     

Seven New Eimeria spp. (Protozoa,Coccidia) from Freshwater Fishes of Canada*

Seven new species of Eimeria are described and figured from the freshwater fishes of Ontario and Quebec, Canada. They are Eimeria catostomi sp. n. and E. fernandoae sp. n. from Catostomus commersoni (Lacépède), E. etheostomae sp. n. from Etheostoma exile (Girard), E. hoffmani sp. n. from Umbra limi (Kirtland), E. micropteri sp. n. from Micropterus dolomieui Lacépède E. pungitii sp. n. from Pungitius pungitius (Linnaeus), and E. salvelini sp. n. from Salvelinus fontinalis (Mitchill). Furthermore, 2 new host records and 2 new distribution records for North America are reported for E. anguillae Léger & Hollande, 1922 and E. truttae Léger & Hesse, 1919 respectively. Finally, morphologically similar oocysts found in various cyprinids are regarded as belonging to E. iroquoina Molnar & Fernando, 1974.     

Sarcocystis lindsayi n. sp. (Protozoa: Sarcocystidae) from the South American opossum, Didelphis albiventris from Brazil

A new species, Sarcocystis lindsayi n. sp., is proposed for a parasite resembling Sarcocystis falcatula. It was obtained from the lungs and muscles of budgerigars (Melopsittacus undulatus) fed sporocysts from a naturally-infected South American opossum, Didelphis albiventris, from Jaboticabal, Brazil. Sarcocysts of S. lindsayi n. sp. in budgerigars are microscopic, up to 600 microm long and up to 50 microm wide. The cyst wall is up to 2 microm thick. Ultrastructurally, the sarcocyst wall consists of numerous slender villar protrusions (up to 2.0 microm long and up to 0.3 microm wide), each with a stylet at its tip. Schizonts in cell culture divide by endopolygeny leaving a residual body. Sporocysts are approximately 12 x 7 microm. The parasite is genetically distinct from other organisms that also cycle between opossums and avian species and resemble S. falcatula. Diagnostic genetic variation has been observed in the nuclear large subunit ribosomal RNA gene, the internal transcribed spacer (ITS-1), and each of two other genetic loci. Although the structure of the sarcocyst wall may not provide sufficient grounds for differential diagnosis, several other attributes including schizont morphology and genetic variation at each of these genetic loci permit identification of S. lindsayi n. sp.. Natural intermediate hosts for S. lindsayi n. sp. are not known, and fuller characterization of these and other Sarcocystis species would benefit from experimental avian hosts that are more permissive to the maturation of sarcocysts.     

Trichodinid Protozoa (Ciliophora: Peritrichida) from Freshwater Fishes of Rybinsk Reservoir,USSR1

During the spring of 1981, trichodinid protozoa were collected from the gills or urinary bladder of the following species of fishes of Rybinsk Reservoir, USSR, located on the upper reaches of the Volga River system: Esox lucius, Rutilus rutilus, Leuciscus idus, Blicca bjoerkna, Abramis ballerus, Pelecus cultratus, Lota lota, and Perca fluviatilis. A total of 13 species of Trichodinidae was recovered from Rybinsk fishes, among which are three new species of the genus Trichodina: T. izyumovae n. sp. from the gills of L. idus, T. borokensis n. sp. from the gills of P. cultratus, and T. kupermani n. sp. from the gills of A. ballerus. Other species of trichodinids reported are T. modesta Lom, 1980; T. nigra Lom, 1969; T. pediculus (O. F. Müller, 1786); T. prowazeki Grupcheva & Lom, 1980; T. rostrata Kulemina, 1968; T. urinaria Dogiel, 1940; T. ophiocephalus Kostenko & Karaev, 1976; Paratrichodina incisa (Lom, 1959); Trichodinella epizootica (Raabe, 1950); and Tripartiella copiosa Lom, 1959. Photomicrographs and morphometric data are presented for each species and aspects of their host and geographic distribution discussed. Trichodina algonquinensis Li & Desser, 1983 is considered a synonym of T. urinaria Dogiel, 1940.     

Eimeria macusaniensis n. sp. (Protozoa: Eimeriidae) of the Alpaca Lama pacos

SYNOPSIS. A new species of coccidium, Eimeria macusaniensis n. sp., is described from the alpaca Lama pacos in Macusani, Peru. The oocysts are ovoid to piriform, 81–107 by 61–80 μ (mean 93.6 by 67.4 μ) with a micropylar cap and elongate ovoid sporocysts 33–40 by 16–20 μ (mean 36.3 by 18.3 μ).     

Sarcocystis dubeyella n. sp. and Sarcocystis phacochoeri n. sp. (Protozoa: Sarcocystidae) from the Warthog (Phacochoerus aethiopicus) in South Africa

ABSTRACT Sarcocystis dubeyella n. sp. and S. phacochoeri n. sp. from muscle fibers of the skeletal musculature of two warthogs in South Africa are described by light and and electron microscopy. Sarcocystis dubeyella sarcocysts are macroscopic (up to 12 mm long and 1 mm wide), with a parasite-induced encapsulation of the host muscle fiber in which the plasma membrane of the latter remained unaltered. The sarcocyst wall is characterized by evenly arranged, irregularly semicircular or rectangular villar protrusions (5.0 T. 2.8-11.0 μm) with indented margins and no specific content. Sarcocystis phacochoeri formed filiform microcysts (up to 4 mm long and 0.13 mm wide). Its cyst wall is provided with tightly packed, molarlike villar protrusions (1.6-3.3 T. 1.7-3.3 μm), with smooth margins, hollow on one side, and with longitudinal condensations of the fine granular matrix at various locations in the interior.     

Henneguya cartilaginis n. sp. (Myxozoa: Myxosporea) in the head cartilage of masu salmon Oncorhynchus masou masou

Henneguya cartilaginis n. sp. (Myxozoa: Myxosporea) is described from wild masu salmon Oncorhynchus masou masou in Hokkaido, Japan. H. cartilaginis n. sp. produced white cysts, up to 3mm in size, in the head of masu salmon. Infected fish exhibited cranial protrusion due to the cysts. Spores (11.4 × 8.6μm) of H. cartilaginis n. sp. were egg-shaped with the posterior end more pointed and possessed two caudal appendages (34.2μm average length). Histological observations revealed that large plasmodia possessing fine fibrous pseudopodia on the surface developed in the head cartilage. H. cartilaginis n. sp. resembles H. cerebralis, which was described from the cranial cartilage of Kosogol grayling Thymallus nigrescens in Mongolia. However, they were distinguishable by spore morphology. Molecular analysis of the 18S rDNA sequences indicated that H. cartilaginis n. sp. was most closely related to Henneguya zschokkei, H. nuesslini and H. salminicola of salmonid fish, with genetic similarities of 95.3%, 95.1% and 93.9%, respectively. Based on these differences in spore morphology, molecular data, the site of infection and geographical distribution, the present species is considered to be a new species.