Light and Electron Microscopy of the Spore of Myxobolus heckelii n. sp. (Myxozoa), Parasite from the Brazilian Fish Centromochlus heckelii (Teleostei, Auchenipteridae)

ABSTRACT. A myxosporean parasitizing the gill filaments of the freshwater teleost fish Centromochlus heckelii collected in the Tocantins River (Lower Amazonian Region, Brazil) is described using light and electron microscopy. This parasite produces spherical to ellipsoidal cyst-like plasmodia up to 250 μm in diameter, with a thick wall strengthened by several stratified juxtaposed crossed collagen layers, whose thickness varies according to the number of the layers. Several compressed fibroblasts are observed among the collagen fibrils. Deposits of spherical dense material are scattered at the internal periphery of the cysts. Plasmodia and different developmental stages, including immature and mature spores, filled the central region of the cysts. The spore body is ellipsoidal in valvar view and biconvex in sutural view. It is formed by two equal-sized and symmetric valves measuring 12.7 μm long (12.2–13.1) ( n =50), 6.6 μm wide (6.3–6.9) ( n =25), and 4.0 μm (3.7–4.4) ( n =20) thick. A thin layer formed by fine and anastomosed microfibrils is observed at the spore surface. Two equal, elongated pyriform polar capsules measure 2.9 μm (2.7–3.3) × 1.7 μm (1.4–2.0) ( n =25), each containing four or five oblique polar filament coils. The binucleated sporoplasm contains numerous spherical sporoplasmosomes, glycogen particles, and a large vacuole with fine granular matrix. Based on the morphological and ultrastructural differences and specificity of the host, we describe this isolate as a new myxosporidian, Myxobolus heckelii n. sp. (Myxozoa, Myxosporea).     

Sphaerospora ovophila N. Sp. and Myxobolus algonquinensis N. Sp. (Myxozoa, Myxosporea), Ovarian Parasites of Fish from Algonquin Park, Ontario, Canada

ABSTRACT. Sphaerospora ovophila n. sp. and Myxobolus algonquinensis n. sp., found in the ovary of the pumpkinseed ( Lepomis gibbosus ) and the golden shiner ( Noremigonus crysoleucas ) respectively from Algonquin Park, Ontario, are described using light and electron microscopy. Ovoid cysts of S. ovophila measured up to 500 pm in length. Monosporic pseudoplasmodia were ovoid or ellipsoid in shape and measured up to 12.5 pm in length. Spores were 7.2–8.4 pm long × 6.0–7.0 pm wide (in sutural plane) × 7.4–8.2 pm thick (perpendicular to sutural plane), with two subspherical polar capsules of equal size measuring 2.7–3.2 × 2.6–3.1 pm and each of which contained a polar filament with 6–7 coils. The spore had a straight sutural ridge which protruded slightly at the anterior end and contained two uninucleate sporoplasms. The spore valve had ornate folds on the posterior end. Cysts of M. algonquinensis ranged from ovoid to elongated ellipsoid in shape and measured up to 800 pm in length. Mature spores measured 13.G15.7 pm long × 10.1–12.1 pm wide × 5.0–6.9 pm thick. with two pyriform polar capsules of equal size measuring 5.1–5.5 pm × 2.5–2.9 pm, each of which contained a polar filament with 4–6 coils. The spores of M. algonquinensis had smooth valves, a straight sutural ridge and a distinct small intercapsular appendix.     

Heterovesicula cowani N. G., N. Sp. (Heterovesiculidae N. Fam.), a Microsporidian Parasite of Mormon Crickets, Anabrus simplex Haldeman, 1852 (Orthoptera: Tettigoniidae)

ABSTRACT. Heterovesicula cowani , n. g., n. sp., is a dimorphic microsporidium described from the adipose tissue of the Mormon cricket, Anabrus simplex Haldeman. Proliferation of the microsporidium is by karyokinesis of uninucleate and binucleate cells to form binucleate and tetranucleate cells, respectively. These cells will undergo binary fission (merogony). Ultimately, the meronts undergo karyokinesis without subsequent cytokinesis producing spherical multinucleate plasmodia that are transitional to 2 types of sporogony. Transitional to disporoblastic sporogony, a fragile interfacial envelope delaminates from the plasmodium with morphogenesis to a monfiliform plasmodium consisting of fusiform binucleate diplokaryotic sporonts. These undergo karyokinesis to form tetranucleate diplokaryotic sporonts that undergo cytokinesis during disintegration of the plasmodium into isolated binucleate sporonts. Transitional to octosporoblastic sporogony, multinucleate plasmodia disintegrate into short monofiliform plasmodia of diplokaryotic sporonts which then segregate while undergoing gradual nuclear dissociation (haplosis by nuclear dissociation). These undergo two sequences of karyokinesis and subsequent multiple fission to form eight uninucleate (haploid) sporoblasts in a fusiform arrangement within a persistent envelope. Binucleate spores are ovocylindrical, about 5.4 × 1.7 μm (fresh), with an isofilar polar filament singly coiled about 11 turns. Uninucleate spores are ovoid to slightly pyriform, 4.0 × 1.7 μm (fresh), with an isofilar filament singly coiled about 9 turns. A new family, Heterovesculidae, is proposed for the new genus.     

Henneguya adherens N. Sp. (Myxozoa, Myxosporea), Parasite of the Amazonian Fish, Acestrorhynchus falcatus

ABSTRACT. A new species of myxosporean from the gill filaments of the freshwater teleost fish, Acestrorhynchus falcatus collected in the Amazon river is described from light and transmission electron microscope observations. The mature spores (total length 32.3 [30.7–35.1] μ) and all developmental stages were found in the same sporogonic plasmodium. The ellipsoidal spore body consists of 2 unequal shell valves adhering together along the suture lines. Each valve, tapering as a caudal projection, forms a long tail (length 20.5 [18.0–21.7] μm). The tail was surrounded by a homogeneous sheath on its length. The polar capsules measuring 3.1 × 1.2 μm contain 3–4 coils of the polar filament. All surfaces of the immature and mature spores were surrounded by a closely adherent homogenous structural sheath, mainly thicker around the tails. The taxonomic affinities of this parasite to other species are discussed.     

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.     

Fine Structure of a New Human Microsporidian, Encephalitozoon hellem, in Culture

Encephalitozoon hellem is a new human microsporidian isolated from corneal biopsies and conjunctival scrapings of three AIDS patients and cultured in Madin Darby canine kidney (MDCK) cells. Encephalitozoon hellem and Encephalitozoon cuniculi display different protein profiles with sodium dodecyl sulfate-polyacrylamide gel electrophoresis and unique antibody binding patterns with murine antisera against Western blots of each organism. Developmental stages of E. hellem in culture are similar to E. cuniculi. Meronts are 1.3–2.7 μm in diameter, develop within a parasitophorous vacuole adjacent to the vacuolar membrane, divide by binary fission, and contain one or two discrete nuclei. Sporonts measure 2 × 3 μm, separate from the vacuolar membrane, and have a thickened outer membrane. Sporoblasts display a tri-layered wall and possess the earliest recognized polar filaments. Mature spores measure 1 × 1.5 μm and are more electron-dense than other stages. Each spore contains a single nucleus, a polar tubule with four to nine coils, thin electron-dense exospore and thick, electron-lucent endospore. Although E. hellem and E. cuniculi differ biochemically and immunologically, their fine structure and development are indistinguishable.     

On the Cytology of Toxoglugea chironomi (Debaisieux, 1931) Jírovec 1936 (Microspora, Thelohaniidae)

ABSTRACT. The light microscopic and ultrastructural characteristics of a microsporidium provisionally identified as Toxoglugea chironomi (Debaiseux, 1931) Jírovec, 1936, is described. It was isolated from oenocytes and adipose tissue of a midge larva of the genus Dicrotendipes . Merozoites are diplokaryotic. The sporogony produces, by fragmentation, eight monokaryotic spores in a sporophorous vesicle. Mature spores are horse-shoe shaped. The total length is about 5.8 μm, the width 0.8-0.9 μm, the external height of the curve 2.3-3.5 μm, and the external width of the curve 3.5-5.2 μm. The polaroplast has lamellar compartments of two types: narrow and closely packed anteriorly, and wider and more loosely arranged posteriorly. The isofilar polar filament is arranged in 8–10 coils in the posterior fourth of the spore. The external nuclear membrane is sometimes continuous with the endoplasmic reticulum. Lamellar and tubular material of exospore construction are present in the episporontal space from the beginning of sporogony. Teratological and normal spores sometimes occur together in the sporophorous vesicle. The identification of the species is discussed and the ultrastructure is compared to Toxoglugea variabilis , the only further species of the genus with known ultrastructural cytology.     

Sphaerospora epinepheli N. Sp. (Myxosporea: Sphaerosporidae) Observed in Grouper (Epinephelus malabaricus)

Sphaerospora epinepheli n. sp. is described from grouper, Epinephelus malabaricus , in cage-cultured and wild fish collected from both coastal lines of southern Thailand. Subspherical to spherical spores and mono- or disporous pseudoplasmodia were observed in the lumen of kidney tubules. Pseudoplasmodia were round to elongate, size range 15.6–22.9 μm (length) × 8.4–21.6 μm (width). Spores were 7.8–10.0 μm (length) × 12.3–14.5 μm (thickness), and 7.0–9.5 μm (width) with two spherical polar capsules of equal size measuring 2.9–4.4 μm in diameter and containing polar filaments with six or seven windings. Two uninucleate sporoplasms showed iodine vacuoles. Blood stages, similar to C-blood protozoans observed from freshwater fish in Europe, were found from peripheral blood smears of grouper. Ultrastructural studies of blood stages showed a similar structure to unidentified mobile protozoans from the blood of carp. Electron dense bodies were observed in the cytoplasm of the primary cell blood stages. Infected proximal-tubular epithelial cells showed highly vacuolated cytoplasm and pycnotic nuclei.     

Nadelspora canceri N. G., N. Sp., an Unusual Microsporidian Parasite of the Dungeness Crab, Cancer Magister

ABSTRACT. The microsporidium Nadelspora canceri n. g., n. sp., is described from the striated musculature of the Dungeness crab ( Cancer magister ) in Oregon, USA. The needle-shaped spores were rounded anteriorly, tapered to a posterior point and measured 7.1–11.8 × 0.2–0.3 μm in fixed preparations. The extremely narrow spore diameter prevented observation of morphological details at the light microscopic level and ultrastructural details of mature spores were difficult to resolve. Meronts were not observed and the monokaryotic merozoites and sporonts were not contained within either parasitophorous or sporophorous vesicles. Sporonts were disporoblastic and gave rise to monokaryotic sporoblasts that became narrow and elongate as they developed into immature spores with a developing polar filament. The nucleus was not clearly resolved in mature spores and may have been surrounded by the lamellar polaroplast. The polar filament was of nearly uniform diameter throughout most of its length and ended abruptly about three-fourths of the distance from the anterior end of the spore. Unusual spherical non-membrane bound granules surrounded the polar filament in a spiral arrangement. The new microsporidium resembles members of the family Mrazekiidiae, but differs in lacking a diplokaryon at any stage. It is probably most closely related to Baculea daphniae from which it differs primarily by spore shape and size. The familial relationships of the genus Baculea have not been determined and it is proposed to include it with Nadelspora in the new family Nadelsporidae.     

Coccidian Parasites (Apicomplexa: Eimeriidae) of Nerodia spp. (Serpentes: Colubridae), with a Description of a New Species of Eimeria

Eimeria conanli n. sp. (Apicomplexa: Eimeriidae) is described from intestinal contents and feces of Nerodia erythrogaster transversa and N harteri harteri from northcentral Texas. Oocysts of the new species are ellipsoid in shape. 17.9 × 13.0(15–21 × 12–15) μm, with a smooth, thin, single-layered wall; shape index 1.4 (1.2–1.5). One to several (usually 2) polar granule(s) and an oocyst residuum are present, but a micropyie is absent. Sporocysts are elongate, 12.9 × 5.2 (13–15 × 5–6) -m, apparently without a true Stieda body structure. Each sporoeyst contains an ellipsoid residuum, 3.9 × 3.2 (3–6 × 2–4) μm, and elongate sporozoites, 11.4 × 2.5 (10–14 × 2–3) μm in situ, each with a spherical or subspherical anterior refractile body and spherical to ellipsoid posterior refractile body. In addition to the new species, oocysts of 4 previously described eimerians from colubrid snakes were found in these hosts.     

Description of the Oocysts of Two New Species of Eimeria (Apicomplexa: Eimerüdae) from the Florida Manatee, Trichechus manatus (Sirenia: Trichechidae)

Two new species of Eimeria (Apicomplexa: Eimerüdae) are described from the feces of the Florida manatee, Trichechus manatus latirostrts (Sirenia: Trichechidae). Oocysts of Eimeria manatus n. sp. are spherical to subsphencal, 11.8 × 10.7 (10.5–13.5 × 9.0–13.5) μ m , with a smooth, thin, bilayered wall; shape index (length/width) 1.1 (1.0–1.3). Micropyle and oocyst residuum absent; polar granule(s) usually present. Sporocysts are ovoid, 8.6 × 5.1 (8.0–9.5 × 5.0–5.5) μm, with thin, membrane–like walls and a knoblike Stieda body; shape index 1.7 (1.4–1.8). Sporozoites elongate, each with a large posterior refractile body. The sporocyst residuum consists of a small cluster or row of few to many small granules. Oocysts of Eimeria nodulosa n. sp. are spherical to subspherical, 15.6 × 14.7 (14.5–17.5 × 13.0–16.0) μm, with a distinctly bilayered wall; shape index 1.1 (1.0–1.2). Unsporulated and freshly sporulated oocysts often possess large, knob–like structures on the external surface of the oocyst wall that support a thin membrane or filament. Micropyle, oocyst residuum and polar granule absent. Sporocysts are ovoid, 10.6 × 5.9 (9.5–12.0 × 5.0–6.5) μm, with a smooth, thin wall and knob–like Stieda body; shape index 1.8 (1.5–2.1). Sporozoites granular and elongate, each with a large posterior refractile body. The sporocyst residuum consists of a loose aggregate or scattered mass of moderately sized granules.     

Ultrastructure of Tricornia muhezae N. G., N. Sp. (Microspora, Thelohaniidae), a Parasite of Mansonia africana (Diptera: Culicidae) from Tanzania

ABSTRACT. Collections of Mansonia africana mosquito larvae were made at one site in N.E. Tanzania in 1985 and 1987 and from two additional sites, both within about 2 mi of the original one in 1987. An octosporous microsporidian, present at all three sites, was found in both years infecting from 7 to 22% of larvae. Spores (stained in Giemsa) measured 3.0 μ m × 0.25 μ m × 2.25 μ m × 0.26 μ m. Ultrastructurally, spores were seen to have an anterior rim surrounding a depressed area where the endospore was at its thinnest. In transmission electron microscopy section, the rim appeared as two processes into which all layers of the wall extended. At the posterior end all layers of the wall extended into a simple knob-like structure which could be interpreted as a section through a crest running longitudinally around the spore. The polar filament was anisofilar, with two anterior coils of greater diameter than the three posterior coils. Although most closely resembling the genera Amblyspora and Parathelohania in the family Thelohaniidae, the species in M. africana differs from the former, which has oval spores, broadly rounded at the ends, and from the latter, which has a prominent, ridged posterior extension to the spores. The new species has been placed in a new genus and the name Tricornia muhezae proposed.     

The Light and Electron Microscopic Cytology of Janacekia adipophila N. Sp. (Microspora, Tuzetiidae), a Microsporidian Parasite of Ptychoptera paludosa (Diptera, Ptychopteridae)

ABSTRACT. The microsporidium Janacekia adipophila n. sp., a parasite of Ptychoptera paludosa larvae in Sweden, is described based on light microscopic and ultrastructural characteristics. Merogonial stages and sporonts are diplokaryotic. Merozoites are formed by rosette-like division. Sporonts develop into sporogonial plasmodia with isolated nuclei. These plasmodia give rise to 8–16 sporoblasts by rosette-like budding. A sporophorous vesicle is initiated by the sporogonial plasmodium. Sporoblasts and spores are enclosed in individual sporophorous vesicles. Granular inclusions of the vesicles, visible using light microscopy, discriminate sporogonial stages from stages of the merogony. The monokaryotic, fresh spores are oval with blunt ends, measuring 4.2-6.3 × 9.1-11.2 μm. Macrospores are formed in small numbers. The spore wall has three subdivisions and the exospore is electron-dense. The polaroplast has two parts: closely arranged lamellae anteriorly, wider sac-like compartments posteriorly. The isofilar polar filament, 191–264 nm wide, has 12-13 coils, which are arranged in one layer in the posterior half of the spore. The electron-dense inclusions of the sporophorous vesicle are modified during sporogony, and vesicles with mature spores are traversed by 21–27 nm wide tubules, which connect the exospore with the envelope of the vesicle. The walls of the tubules, the envelope of the vesicles, and the surface layer of the exospore are all identical double-layered structures. The microsporidium is compared to microsporidia of Ptychopteridae and Tipulidae and to related microsporidia of the family Tuzetiidae.     

Myxobolus albi n. sp. (Myxozoa) from the Gills of the Common Goby Pomatoschistus microps Krøyer (Teleostei: Gobiidae)

ABSTRACT. A recent investigation into the myxozoan fauna of common gobies, Pomatoschistus microps , from the Forth Estuary in Scotland, revealed numerous myxosporean cysts within the gill cartilage. They were composed of polysporous plasmodia containing myxobolid spores that were morphologically different from the other known species of Myxobolus and from the myxosporeans previously recorded from this host (i.e. the ceratomyxid Ellipsomyxa gobii , infecting the gall bladder, and the kudoid Kudoa camarguensis , infecting the muscle tissues). Spores were ovoid, 9.4 × 9.1 μm with a thickness of 6.6 μm, with two pyriform polar capsules, the polar filaments of which had four to five turns. Molecular analysis of the parasite's small subunit rDNA region, based upon a contiguous sequence of 1,558 base pairs, discriminated it from other myxosporean species that have been characterized so far. A comparison of the spore morphology and the molecular sequences determined for this new isolate with other myxozoans described to date, confirmed its identity as a previously unknown myxobolid supporting the proposal that this isolate be elevated to the species level as a new species within the genus Myxobolus . A phylogenetic analysis places this new myxobolid, Myxobolus albi n. sp., in a basal position of a clade containing the majority of Henneguya spp. sequenced to date and various Myxobolus spp.     

Myxobolus dahomeyensis infection in ovaries of Tilapia species from Benin (West Africa)

The prevalence of Myxobolus dahomeyensis in ovaries of Tilapia zillii was 31·6% and 18·3% in Sarotherodon melanotheron melanotheron . The parasite induced destruction of the oocytes and host castration. Its ovoid spore was 6·5–12·0 × 6·0–8·0 μm and the polar capsules averaged 3·6 × 2·2 μm ( n = 30).     

Encephalitozoon-Like Organisms in Patients with Alveolar Hydatid Disease: Cell Culture, Ultrastructure, Histoimmunochemical Localization and Seroprevalence

ABSTRACT. We found Encephalitozoon -like organisms in an in vitro culture of a human liver lesion which was due to larval Echinococcus multilocularis. The organisms developed in the same fashion as an Encephalitozoon cunculi. The spores that developed in parasitophorous vacuoles were 2.0–2.6 × 1.1–1.5 μm: each contained a single nucleus and 4–5 polar tubule coils, closely resembling E. cuniculi in its ultrastructure. Mature spores were collected from the supernatants by the use of Percoll centrifugation resulting in the banding of the spores on continuous gradients. We prepared three sorts of spores which were different in buoyant density in 0.15 M NaCl: 1.05–1.07 g/ml spores, 1.12 g/ml spores, and spores of over 1.14 g/ml. Polyclonal antibodies to a pool of each spore preparation were produced in a rabbit and applied to the detection of microsporidian antigen in situ. The histoimmunoperoxidase (HIP) procedure was used to detect the microsporidian antigen in echinococcal liver lesions from patients with alveolar hydatid disease (AHD). Ten echinococcal liver lesions from different AHD patients were examined and four were found to be positive in the HIP test. The Percoll-separated spores were also used as an antigen to detect for antibodies in the sera from the patients with AHD by Western blotting. Antibodies were detected in 62 (52%) of the 119 AHD patients and in only 8 (5%) of the 159 normal healthy individuals.     

Tuzetia boeckella sp. nov. (protozoa: Microsporida), a parasite of Boeckella triarticulata (Copepoda: Calanoidea) in Australia

A hitherto undescribed microsporidan has been found in the Australian freshwater copepod, Boeckella triarticulata, collected from Lake Burley Griffin, Canberra. We name this protozoan Tuzetia boeckella n. sp. and describe it in this paper. Large numbers of spores were found in the muscle of both sexes and all stages of the animals. The pyriform spores measured 5.1 × 2.7 μm with the extruded polar filament measuring 102 μm. Ultrastructural studies revealed the presence of a pansporoblastic membrane around each spore. The polar filament was arranged in a single row of 13–14 turns and decreased in diameter toward the posterior end. Few details of the life cycle were elucidated; however, evidence is presented for each sporont forming eight spores. Differentiating characters to distinguish this species from the six other known members of the genus are given.     

Ultrastructural and molecular characterization of a new microsporidium parasite from the Amazonian fish, Gymnorhamphichthys rondoni (Rhamphichthyidae)

A new species of a microsporidium found in the freshwater teleost Gymnorhamphichthys rondoni, collected on the lower Amazon River, is described based on light, ultrastructural, and phylogenetic studies. This parasite develops in the skeletal muscle of the abdominal cavity, forming whitish cyst-like structures containing numerous spores. Mature spores, lightly pyriform to ellipsoidal with rounded ends and measuring 4.25 ± 0.38 × 2.37 ± 0.42 μm (n = 30), were observed. The spore wall, which measured about 102 nm, was composed of 2 layers with approximately the same thickness. The isofilar polar filament was coiled, with 9-10 (rarely 8) turns. The posterior vacuole appeared as a pale area, occupying about 1/3 of the spore length, and contained a spherical posterosome composed of granular material that was denser at the periphery. The myofibrils located near the spores appeared to be in advanced degradation. Molecular analysis of the rRNA genes, including the ITS region, and phylogenetic analyses using maximum parsimony, maximum likelihood, and Baysesian inference were performed. The ultrastructural characteristics of the spores and the phylogenetic data strongly suggested that it is a new species related to Kabatana, Microgemma, Potaspora, Spraguea, and Tetramicra. We named this new microsporidian from Amazonian fauna as Kabatana rondoni n. sp.     

Six new species of microsporidia of the genus Amblyospora (Microspora: Amblyosporidae) from blood sucking mosquitoes (Diptera: Culicidae) from the west Siberia

Microsporidia of the genus Amblyospora parasiting the adipose body of mosquito larvae of the genus Aedes and Culex has been studied with both light and electron microscopy. Six new species of microsporidia are described based on ultrastructural characteristics of spores and sporogony stages. Amblyospora flavescens sp. n. Mature spores are egg-shaped. The spore wall with three layers, about 165 nm. Exospore is two-membranous. Subexospore is absent. Endospore is electron-translucent. Polaroplast consists of three parts: lamellar, large vesicular, lamellar. The anisofilar polar filament with 10--11 coils (3 1/2 + 2 1/2 + 4-5). Fixed spores are 6.3 +/- 0.1 x 4.24 +/- 0.1 microm. Amblyospora kolarovi sp. n. Mature spores are egg-shaped. The spore wall with three layers, about 265-315 nm. Exospore shapes tucks on the surface of spore. It is two-membranous. Subexospore is quagge, structural. Endospore is electron-translucent. Polaroplast consists of two parts: lamellar and large vesicular. The anisofilar polar filament with 11-13 coils (3 + 8-10). Fixed spores are 5.4-5.6 x 3.5-4.2 microm. Amblyospora orbiculata sp. n. Mature spores are widely egg-shaped. On a back pole there is a small concavity. The spore wall with three layers, about 155 nm. Exospore is shapes tucks on a surface of spore. It is two-membranous. Subexospore is absent. Endospore is electron-translucent. Polaroplast consists of three parts: lamellar, vesicular, lamellar. Polar filament is anisofilar, with 11 1/2 coils (4 1/2 + 1 + 6). Fixed spores are 6.3 +/- 0.1 x x 4.0 +/- 0.1 microm. Amblyospora rugosa sp. n. Mature spores are egg-shaped. On a back pole there is a small concavity. The spore wall with three layers, about 225 nm. Exospore is shapes tucks on a surface of spore. It is two-membranous. Subexospore is quaggy, structural. Endospore is electron-translucent. Polaroplast lamellate. Polar filament is anisofilar, with 17 1/2 coils (3 1/2 + 1 + 13). Fixed spores are 5.3 +/- 0.1 x 3.7 +/- 0.1 microm. Amblyospora undata sp. n. Mature spores are egg-shaped. The spore wall is three-layered, about 220 nm. Exospore is shapes tucks on a surface of spore. It is two-membranous. Subexospore is quaggy, structural. Endospore is electron-translucent. Polaroplast lamellate. The anisofilar polar filament with 8 coils (3 + 5). Fixed spores are 5.0 +/- 0.1 x 3.0 +/- 0.1 microm. Amblyospora urski sp. n. Mature spores have widely oval form. The back pole is concave. The spore wall with three layers, about 280 nm. Exospore is shapes tucks on a surface of spore. It is two-membranous. Subexospore is quaggy, structural. Endospore is electron-translucent. Polaroplast lamellate. Polar filament is anisofilar, with 6 coils (2 + 4). Fixed spores are 4.4 +/- 0.1 x 2.9 +/- 0.1 microm.     

Eimeria procyonis sp. n., an Isospora sp., and a Redescription of E. nuttalli Yakimoff and Matikaschwili, 1932 (Protozoa: Eimeriidae) from the American Raccoon (Procyon lotor)

SYNOPSIS. Thirty-two of 48 raccoons examined were infected with a previously undescribed species of Eimeria which is herein named E. procyonis. Of the 32 infected animals, 10 also harbored E. nuttalli and 1 had Isospora sp. oocysts.
The ellipsoid to ovoid oocysts of E. procyonis measured 23.4 × 18.0 (16–29 × 13–24) μm; its sporocysts measured 12.1 × 9.3 (11.5–15 × 7–10) μm, each containing a slightly flattened substiedal body. The sporocyst residuum consisted of numerous scattered granules each ∼1 μm in diameter. The oocyst wall was double-layered. The outer layer appeared rough and pitted, measuring 1.5 μm, except at the micropyle where it was 1 μm thick.
The oocysts of the Isospora sp. measured 16.8 × 13.7 (16–18.5 × 12.5–15.5) μm. The wall consisted of a single layer ∼0.5 μm thick. The sporocysts measured 11.2 × 9.1 (9.5–11.5 × 8–10) μm, and each contained 4 elongate sporozoites. The oocysts of E. nuttalli measured 17.5 × 13.6 (12-21 × 11-15) μm, with a smooth single-layered wall approximately 0.7 μm thick. The sporocysts measured 12.2 × 7.1 (9-13 × 5.5–11) μm. Each sporocyst had a thin, dark, Stieda body and the sporocyst residuum consisted of many fine granules.