Correlative light and electron microscopy of wall formation in Eimeria nieschulzi

Coccidian parasites possess complex life cycles involving asexual proliferation followed by sexual development leading to the production of oocysts. Coccidian oocysts are persistent stages which are secreted by the feces and transmitted from host to host guaranteeing life cycle progression and disease transmission. The robust bilayered oocyst wall is formed from the contents of two organelles, the wall-forming bodies type I and II (WFBI, WFBII), located exclusively in the macrogametocyte. Eimeria nieschulzi has been used as a model parasite to study and follow gametocyte and oocyst development. In this study, the gametocyte and oocyst wall formation of E. nieschulzi was analyzed by electron microscopy and immuno-histology. A monoclonal antibody raised against the macrogametocytes of E. nieschulzi identified a tyrosine-rich glycoprotein (EnGAM82) located in WFBII. Correlative light and electron microscopy was used to examine the vesicle-specific localization and spatial distribution of GAM82-proteins during macrogametocyte maturation by this monoclonal antibody. In early and mid-stages, the GAM82-protein is ubiquitously distributed in WFBII. Few hours later, the protein is arranged in subvesicular structures. It was possible to show that the substructure of WFBII and the spatial distribution of GAM82-proteins probably represent pre-synthesized cross-linked materials prior to the inner oocyst wall formation. Dityrosine-cross-linked gametocyte proteins can also be confirmed and visualized by fluorescence microscopy (UV light, autofluorescence of WFBII).

Epidemiological survey and risk factor analysis on Eimeria infections in calves and young cattle up to 1 year old in Colombia

A large-scale cross-sectional epidemiological study was conducted to evaluate prevalence, species diversity, and associated risk factors of Eimeria infections in 55 cattle farms across seven states of Colombia, including subtropical and tropical regions. In total, 1333 fecal samples from young animals (< 1 year of age) were examined at a single sampling date from August 2016 to December 2016. Flotation and McMaster techniques were conducted for parasitological investigation. Excreted Eimeria oocysts were allowed to sporulate in vitro and thereafter identified to species level based on morphological and morphometric characteristics. The overall Eimeria prevalence was 75.5% (1006/1333), with no difference observed between age categories. In total, 13 different Eimeria species were identified. The most prevalent species was E. bovis (33.5%), followed by E. auburnensis (12.5%) and E. zuernii (11.9%). Analysis of extrinsic associated risk factors revealed the floor type, feeding system, watering system, and herd size as significant (p < 0.05) risk factors for Eimeria spp. infections. Based on these data, it can be assumed that bovine coccidiosis infections occur ubiquitously in the country and might play an important role especially in its subclinical form by affecting production parameters in conventional cattle management systems.

Eimeria aegoliusia n. sp. (Sporozoa: Eimeriidae) from the northern saw-whet owl Aegolius acadicus (Gmelin) (Strigiformes: Strigidae) in Mexico

A new coccidian species (Chromista: Sporozoa: Eimeriidae) collected from the northern saw-whet owl Aegolius acadicus (Gmelin) is reported from Mexico. Eimeria aegoliusia n. sp. has subspherical oöcysts, with smooth, bi-layered wall. Micropyle and oöcyst residuum are both absent and a polar granule is present. To date, eight species of Eimeria Schneider, 1875 have been described from strigiform birds. Mean dimensions of sporulated oöcysts (23.7 × 22.4 µm) and sporocysts (12.8 × 8.3 µm) appear to be considerably smaller than those from other Eimeria spp. with owl definitive hosts: E. atheni Chauhan & Jain, 1979; E. megabubonis Upton, Campbell, Weigel & McKown, 1990; E. spenotytoi Carini, 1939; E. strigis Kutzer, 1963; and E. varia Upton, Campbell, Weigel & McKown. Dimensions of these sporulated oöcysts appear to be larger than those in E. bemricki Averbeck, Cooney, Guarnera, Redig & Stromberg, 1998. The presence of polar granules and their number allowed differentiation from E. bubonis Cawthorn & Stockdale, 1981 and E. nycteae Volf, Koudela & Modry, 1999. This is the first description of an eimeriid coccidian infecting A. acadicus.

Helminth (Cestoda, Nematoda) and coccidian (Apicomplexa: Eimeriidae) parasites of the eastern small-footed myotis, Myotis leibii (Chiroptera: Vespertilionidae) from Arkansas, with a description of a new species of Eimeria

During May and July 2016, 32 eastern small-footed myotis (Myotis leibii) were collected from five counties of northwestern Arkansas and their faeces examined for coccidian parasites. Four of 32 (13%) M. leibii harboured an eimerian that we describe here as new. Oocysts of Eimeria sassei sp. n. were ovoidal to ellipsoidal with a bi-layered wall and measured (length × width, L × W) 18.3 × 15.2 µm, with an L/W ratio of 1.2. A micropyle and oocyst residuum were absent but 1-2 polar granules were present. Sporocysts were ovoidal, 9.6 × 6.3 µm, with an L/W ratio of 1.5. A pronounced, button-like Stieda body was present but substieda and parastieda bodies were absent. A sporocyst residuum was present as distinct aligned or dispersed granules. One bat that we found dead was examined for helminth parasites. It harbored the tapeworm, Vampirolepis sp. and a nematode, Seuratum cancellatum. This is the first coccidian as well as the second helminths reported from M. leibii. In addition, this is the seventh species of coccidian parasite documented from Arkansas bats.

Two new species of Eimeria Schneider, 1875 (Apicomplexa: Eimeriidae) from emerald tree skinks, Lamprolepis smaragdina (Lesson) (Sauria: Scincidae) from Papua New Guinea and the Philippines

Two new species of Eimeria Schneider, 1875, from emerald tree skinks, Lamprolepis smaragdina (Lesson) are described from specimens collected in Papua New Guinea (PNG) and the Philippines. Oöcysts of Eimeria nuiailan n. sp. from the only L. smaragdina from PNG are ovoidal, with a smooth, colourless, bi-layered wall, measure 23.7 × 19.1 μm, and have a length/width (L/W) ratio of 1.3; both micropyle and oöcyst residuum are absent, but a fragmented polar granule is present. Sporocysts are ovoidal to ellipsoidal, 11.9 × 7.0 μm, L/W 1.7, and the wall is composed of two valves joined by a longitudinal suture; neither Stieda nor sub-Stieda bodies are present; a sporocyst residuum is present as a compact mass of granules. Sporozoites are elongate, 14.6 × 2.6 μm, and contain anterior and posterior refractile bodies with a nucleus between them. Oöcysts of Eimeria auffenbergi n. sp. from L. smaragdina collected in the Philippines are ovoidal, with a smooth, colourless, bi-layered wall, measure 19.9 × 15.8 μm, L/W 1.3; both micropyle and oöcyst residuum are absent, but one to four polar granules are present. Sporocysts are ovoidal to ellipsoidal, 10.3 × 5.8 μm, L/W 1.8, and the wall is composed of two valves joined by a longitudinal suture; neither Stieda nor sub-Stieda bodies are present; a sporocyst residuum is composed of dispersed granules.

Prevalence, infectivity and oocyst sporulation time of rabbit-coccidia in Taiwan

Prevalence of Eimeria species parasitizing rabbits (Oryctolagus cuniculus) in Taiwan were investigated. Six Eimeria species, namely: Eimeria media (prevalence, 158/642; 24.6%), Eimeria magna (101/642; 15.7%), Eimeria perforans (58/642; 9.0%), Eimeria coecicola (46/642; 7.2%), Eimeria piriformis (16/642; 2.5%), and Eimeria exigua (9/642; 1.4%) were observed. The overall prevalence of these coccidial infections in rabbits from pet shops and farms was 46.2% and 41.7%, respectively. Concurrent infections involving 2 or 3 species were often observed, while quadruple-infection was rare. Significant differences (p < 0.005) in prevalence were observed between the adult and juvenile rabbits. The minimum time required for oocyst sporulation of E. media, E. piriformis, E. magna, E. perforans, E. exigua, E. coecicola were 10, 20, 32, 12, 16, and 36 hr, respectively. This is the first report on the prevalence of Eimeria intestinal infection in commercial domestic rabbits in Taiwan. We demonstrated that these rabbit-infecting Eimeria species have high biopotential in that the ingestion of a single sporulated oocyst could successfully produce patent infection in a rabbit. In addition, they also possess high host specificity in that they could not infect mice, golden hamsters, Mongolian gerbils, rats, and guinea pigs.

Light microscopic study on Eimeria species infecting Japanese quails reared in Saudi Arabian farms

Japanese quails Coturnix coturnix japonica reared in economic farms were individually investigated for coccidian infections. The results indicated the absence of infections in birds younger than 1 month. An Eimeria infection rate of up to 80% was detected in birds 7-9 weeks old with a general infection rate of 29%. The infection rate decreased to 21.42% in birds older than 10 weeks. Morphometric characteristics of freshly shed, unsporulated oocysts were taken. These oocysts appeared pale yellow in color, were oval to subspherical in shape being limited by a bilayered oocyst wall of 1.2 microm. The unsporulated oocysts measured 17.73 +/- 12.92 x 12.79 +/- 1.69 microm (mean of 100) and possessed a polar granule, a micropyle and an oocyst residuum. The sporulation took 72 h and resulted in the formation of four elongated sporocysts containing two sporozoites, in addition to a stieda body and a sporocyst residuum. The life cycle of this Eimeria species was followed in experimentally infected quails. Three asexual generations (at 60, 78, and 96 h p.i.) were detected in the epithelium of the small intestine before the sexual cycle started at 84 h p.i. The prepatent period was 5 days, while the patent period covered 6-7 days. Besides this well-defined species, another Eimeria species occurred, the oocysts of which were excreted in low numbers and were characterized by the absence of a micropyle and an oocyst residuum. These oocysts measured 15.73 +/- 2.22 x 14.18 +/- 1.89 microm (mean of 100) and sporulated already within 60 h.

Endogenous development, pathogenicity and host specificity of Eimeria cahirinensis Couch, Blaustein, Duszynski, Shenbrot and Nevo, 1997 (Apicomplexa: Eimeriidae) from Acomys dimidiatus (Cretzschmar 1826) (Rodentia: Muridae) from the Near East

Eimeria cahirinensis Couch et al. 1997 was found in faecal samples of Acomys dimidiatus from three different localities in the Near East. Twenty-two of 104 (21%) A. dimidiatus trapped on both the south- and north-facing slopes of "Evolution Canyon", Lower Nahal Oren, Mt. Carmel, Israel in August 2001 and 2002 were infected with E. cahirinensis. Oocysts were also obtained from a single individual of A. dimidiatus trapped in Wadi Ramm, Jordan in the summer of 1999. Laboratory-reared spiny mice (Acomys spp.) were inoculated to determine the prepatent and patent period, sporulation time, site of infection, immunogenicity, pathogenicity, pathology and morphology of endogenous stages of E. cahirinensis. Both asexual and sexual stages were localised in the apical part of duodenal and jejunal villi. An experimental inoculation of representatives of several rodent genera revealed the host range of E. cahirinensis to be limited to the genus Acomys.

[Coccidia (eimeriidae) of fishes (Cypriniformes) in the continental waters of Russia]

Thorough data on 67 coccidian species of the genera Eimeria, Goussia, and Isospora parasitizing fishes in the continental waters of Russia are given. Authors, year of description, synonyms, morphofunctional organization, and list of the hosts are reported for each species. The paper is supplied with figures of the exogenic stages of coccidia (oocysts).

Life cycle of Eimeria krijgsmanni-like coccidium in the mouse (Mus musculus)

Life cycle of Eimeria krijgsmanni-like coccidium isolated from the feces of naturally infected mice purchased from commercial sources was examined. The parasite was purified by single oocyst isolation and maintained by passage in the mice before experiments. The sporulated oocysts were ovoid or ellipsoid, measuring 19.3 x 14.8 microm on average. One or two small polar granules were present. Micropyle and oocyst residuum were absent. Sporocysts were ellipsoid, measuring 11.6 x 7.2 microm on average with a small Stieda body and sporocyst residuum. Six groups of respective 5 mice (4-week-old) were inoculated with doses varying from 2.0 x 10(1) to 10(6) oocysts. All the mice examined began to shed oocysts from 7 day postinoculation (PI) and their maximum number of oocysts per gram of feces were 10(6) on day 8 PI. Patency was 6 or 7 days. This parasite had severe virulence to the mice that is, the mice given 10(6) oocysts showed anorexia, diarrhoea and rough hair from 1 day and all of them died on day 3 PI. The mice given 10(3) or more oocysts showed the clinical signs described above from day 5 and 4 of them received 10(5) died on day 9 or 10 PI. The parasites occurred within the epithelial cells of cecum, colon and rectum of infected mice. Sporozoites, 13.9 x 3.0 microm, with two large refractil bodies on side of the nucleus located subcentrally were observed on day 1 and 2 PI. Merozoites were first observed at 24 hr PI, and sexual stages were found from 4 day PI. No parasites were detected in the small intestine and mecenteric lymph nodes.

Eimeria lokuma n. sp. (Apicomplexa: Eimeriidae), a new coccidium from the African helmeted turtle Pelomedusa subrufa (Lacépède) (Testudines: Pelomedusidae)

Coprological examination of nine African helmeted turtles Pelomedusa subrufa from Kenya revealed the presence of a new coccidium belonging to Eimeria Schneider, 1875. Oöcysts of Eimeria lokuma n. sp. are spherical to sub-spherical, 13.6 (13-14.5) x 13 (12-14) microm, lack a micropyle and a polar granule, but possess a granular oöcyst residuum. The sporocysts are elongate, oval to spindle-shaped and 8.3 (7.5-9.5) x 4.4 (4-5) microm. The Stieda body is relatively low, flat and wide, and covered with a membranous, highly flexible, scarf-like structure which protrudes from its strengthened margins. The sporozoites possess two refractile bodies. Based on the presence of a Stieda body, the described species is classified as Eimeria (sensu stricto).

The third newly discovered Eimeria species (Protozoa: Eimeriidae) described from wild reindeer, Rangifer tarandus, in Iceland

Fecal samples from 56 adult reindeer from eastern Iceland were examined for coccidian parasites. One Eimeria species was found in an 8-year-old male. Prevalence of infection was 1.8%; oocyst per gram (opg) value was 150. The coccidium was identified and described as a new species. The sporulated oocysts are ellipsoidal and average size is 30.0 x 21.1 microm. The oocyst has two distinct walls. Wall thickness is approximately 1.0 microm, and the outer wall, approximately four-fifths of total thickness, is generally smooth and appears bicoloured. The outermost portion is light blue, and the innermost portion, yellow to pale brown. The inner wall is dark brown. Oocysts contain a prominent polar granule but are devoid of a micropyle. Oocysts enclose four spindle-shaped sporocysts with a rounded end opposite to the Stieda body. The average size of sporocysts is 15.3 x 6.5 microm. Sporocysts contain a granular sporocyst residuum that usually forms a cluster between the sporozoites and one large refractile body in each sporozoite.

Seven new species of Eimeria Schneider, 1875 (Apicomplexa: Eimeriidae) from colubrid snakes of Guatemala and a discussion of what to call ellipsoid tetrasporocystic, dizoic coccidia of reptiles

During a survey of Guatemalan herpetofauna in the summers of 1998-2000, 29 presumed new species of Eimeria Schneider, 1875 were found, seven of which have a distinct elongate-ellipsoidal shape (L/W ratio >or= 1.7) and are described herein. Six of the seven new species are similar in oöcyst length, width and L/W ratio and sporocyst length, width and L/W ratio, lack a micropyle, oöcyst residuum, Stieda body, sub-- and parastieda bodies, have a polar granule and sporocyst residuum, and their sporocysts appear to have dehiscence sutures. The seventh is slightly smaller and has sporocysts with a Stieda body. The new species are: E. coniophanes n. sp - whose sporulated oöcysts from Coniophanes fissidens are 29.2x14.9 (27-31x13-16) microm, with sporocysts 10.0 x 7.8 microm; E. coniophis n. sp. -from Conophis lineatus are 32.0x16.5 (30-34x14-18) microm, with sporocysts 10.2 x 8.9microm; E. dryomarchoni n. sp. - from Drymarchon corais are 32.2x17.7 (31-34x17-19) microm, with sporocysts 10.7 x 8.6 microm; E. leptophis n. sp. - from Leptophis mexicanus are 29.5x17.0 (28-31x16-18) microm, with sporocysts 10.0 x 9.1 microm; E. oxybelis n. sp. - from Oxybelis aeneus are 31.8x16.5 (29-33x15-18) microm, with sporocysts 10.3 x 8.8 microm; and E. scaphiodontophis n. sp. - from Scaphiodontophis annulatus are 30.0x15.3 (28-33x14-16) microm, with sporocysts 9.9 x 7.9 microm. Sporulated oöcysts of E. siboni n. sp. from Sibon nebulata are 24.3x14.2 (21-27x13-16) microm, with sporocysts 10.0 x 7.1 microm and with a Stieda body. We conclude that until all aspects of each life-cycle are known, it is prudent at this time to name all tetrasporocystic dizoic coccidia from snakes as members of Eimeria rather than place some of them in Choleoeimeria Paperna & Landsberg, 1989.

Two new species of Eimeria Schneider 1875 (Apicomplexa: Eimeriidae) from the broad-toothed field mouse, Apodemus mystacinus Danford and Alston 1877 (Rodentia: Muridae) from Jordan

Coprological examination of 40 Apodemus mystacinus Danford and Alston 1877 from Jordan revealed oocysts of three species of genus Eimeria. Two species are described as new. Eimeria zuhairamri sp. n. has broadly ellipsoidal oocysts 29.6 (27.0-34.0) x 23.3 (22.0-25.0) mum with distinctly granulated wall and oocyst residuum. Endogenous development occurs in jejunum and ileum. Eimeria alorani sp. n. has oocysts 26.9 (23.0-29.0) x 19.3 (18.0-22.0) mum with smooth wall and absent residuum. Endogenous development is confined to the caecum. The third species, developing in jejunum, has oocysts morphologically indistinguishable from Eimeria uptoni. The identity of E. uptoni and the taxonomy of Eimeria of Apodemus are discussed.

[New species of coccidia Eimeria stizostedioni sp. n. (Sporozoa: Coccidea) from the pike perch Stizostedion lucioperca (Perciformes)]

A new coccidia species Eimeria stizostedioni from the pikeperch Stizostedion lucioperca (Perciformes) is described. Localities: Neva river. Prevalence: 20% (1/5). Intensity of infection weak. Oocysts 7.5-8.0 x 10.0-12.5 microns. The form varies from oval up to ovoid; a wall is sleek, colourless, single-layer two-planimetric, micropyle, the polar granules and residual body are absent. Sporocysts 3.5 x 6.5 microns, with Stieda body and residual body represented by few small granules. Sporogony is endogenous.

Intestinal coccidia (Apicomplexa: Eimeriidae) of Brazilian lizards. Eimeria carmelinoi n.sp., from Kentropyx calcarata and Acroeimeria paraensis n.sp. from Cnemidophorus lemniscatus lemniscatus (Lacertilia: Teiidae)

Eimeria carmelinoi n.sp., is described in the teiid lizard Kentropyx calcarata Spix, 1825 from north Brazil. Oocysts subspherical to spherical, averaging 21.25 x 20.15 micro m. Oocyst wall smooth, colourless and devoid of striae or micropyle. No polar body or conspicuous oocystic residuum, but frequently a small number of fine granules in Brownian movement. Sporocysts, averaging 10.1 x 9 microm, are without a Stieda body. Endogenous stages characteristic of the genus: intra-cytoplasmic, within the epithelial cells of the ileum and above the host cell nucleus. A re-description is given of a parasite previously described as Eimeria cnemidophori, in the teiid lizard Cnemidophorus lemniscatus lemniscatus. A study of the endogenous stages in the ileum necessitates renaming this coccidian as Acroeimeria cnemidophori (Carini, 1941) nov.comb., and suggests that Acroeimeria pintoi Lainson & Paperna, 1999 in the teiid Ameiva ameiva is a synonym of A. cnemidophori. A further intestinal coccidian, Acroeimeria paraensis n.sp. is described in C. l. lemniscatus, frequently as a mixed infection with A. cnemidophori. Mature oocysts, averaging 24.4 x 21.8 microm, have a single-layered, smooth, colourless wall with no micropyle or striae. No polar body, but the frequent presence of a small number of fine granules exhibiting Brownian movements. Sporocysts 9 x 8, without a Stieda body. Endogenous stages epicytoplasmic, characteristic of the genus, in the upper ileum. The importance of a study of the endogenous stages of eimeriid coccidia is discussed.

Electron microscopic study on the endogenous development of Eimeria mulardi, Chauve, Reynaud and Gounel, 1994: a coccidium from the mule duck

An electron microscopic study of the endogenous development of Eimeria mulardi Chauve, Reynaud and Gounel, 1994 was carried out in mule ducks which are hybrids of the domestic duck (Anas platyrhynchos) and the muscovy duck (Cairina moschata). All of the endogenous stages were seen within the nucleus of the host cell. Merozoites arose from ectomerogony and three mutually similar merogonies were noted. The asexual stages were found in leukocyte-like cells in the lamina propria of the jejunum, ileum and caecum, while the gamonts developed in glandular epithelial cells in the same part of the intestine.

Eimeria hajeki n. sp. (Apicomplexa: Eimeriidae), a new coccidian parasite of the pygmy chameleon, Rampholeon temporalis (Matschie, 1892) (Reptilia: Chamaeleonidae) from Usambara Mountains, Tanzania

Fecal samples from 10 pygmy chameleons, Rampholeon temporalis (Matschie, 1892), an endemic species of the Usambara Mountains in northeastern Tanzania, were examined for coccidian parasites. Two (20%) chameleons were found to be passing oocysts of Eimerio Schneider. Comparison with other species of Eimeria indicates that the coccidian found represents a new species. Sporulated oocysts of Eimeria hajeki n. sp. are oval, 30.2 (29-31) by 23.5 (22-25) microm, with a shape index (length/width) of 1.3 (1.2-1.4) and a 2-microm-thick rough, bilayered wall. Micropyle and polar granule are absent. Sporocysts are oval to rhomboidal, 10.8 (9-11.5) by 8.8 (7.5-10) microm, with a shape index of 1.2 (1.15-1.3) and a wall composed of 2 valves joined by a suture.

Five new species of Coccidia (Apicomplexa: Eimeriidae) from colubrid snakes of Ecuador

Fecal samples from 11 colubrid snakes, representing 10 species, collected in Ecuador during October 1994 were examined for coccidian parasites. Feces of 4 individuals, representing 4 host species, contained coccidian oocysts. Three species of Eimeria and 2 species of Isospora were observed and are described here as new. Oocysts of both Eimeria and Isospora were found in the feces of a slug-eating snake, Dipsas vermiculata. Sporulated oocysts of the Eimeria sp. are spheroid to subspheroid, 16.7 by 16.6 microm (14-18 by 14-18 microm) and those of the Isospora sp. are spheroid and 15.0 microm (13-18 microm) in diameter. Imantodes cenchoa, the common bluntheaded treesnake, was infected with a species of Eimeria. These sporulated oocysts are ellipsoid, 23.3 by 16.2 microm (25-21 by 15-17 microm). Sporulated eimerian oocysts from Leptodeira annulata, the southern cat-eyed snake, are subspheroid, 22.5 by 18.8 microm (19-26 by 17-21 microm). Feces of a juvenile Imantodes lentiferus, the bluntheaded vine snake, contained ovoid to ellipsoid isosporan oocysts, which measured 21.6 by 15.0 microm (20-23 by 14-16 microm) when sporulated.

Five new species of coccidia (Apicomplexa: Eimeriidae) from Madagascan chameleons (Sauria: Chamaeleonidae)

Coprological examination of 19 Madagascan chameleons of the genera Furcifer and Brookesia revealed the presence of five new coccidian species. Isospora brygooi n. sp. from Furcifer pardalis has spherical to subspherical oöcysts with a slightly pitted wall, 20.7 (17-24.5) x 19.3 (16-23) microm and broadly ellipsoidal sporocysts, 12.2 (11.5-13) x 8.1 (8-8.5) microm, with Stieda and substieda bodies. Oöcysts of Eimeria glawi n. sp. from Furcifer pardalis are cylindrical to ellipsoidal, 27.7 (26-29.5) x 18.4 (17-19) microm, with ellipsoidal sporocysts, 7.3 (6.5-8) x 5.2 (5-5.5) microm. E. vencesi n. sp. described from F. pardalis has spherical to subspherical oöcysts, 14.3 (13-15.5) x 13.0 (12-13) microm, with small granules, one to three globular polar granules and ellipsoidal sporocysts, 7.3 (6.5-8) x 5.2 (5-5.5) microm. E. worthi n. sp., described from Furcifer oustaleti has spherical oöcysts, 17.9 (17.5-19.0) x 15.0 (14.5-16.0) microm without a polar granule and ellipsoidal to cylindroidal sporocysts, 8.2 (7.0-9.5) x 5.8 (5.0-6.5) microm. Oöcysts of E. brookesiae n. sp. from Brookesia decaryi are cylindrical, 25.6 (23-27) x 15.0 (13-16) microm with ellipsoidal sporocysts, 10.1 (9-11) x 6.9 (6-7) microm. Endogenous development of E. vencesi is confined to the intestine, while that of E. glawi occurs in the gall-bladder.

A new species of Eimeria (Apicomplexa, Eimeriidae) from the weedy sea dragon Phyllopteryx taeniolatus (Osteichthyes: Syngnathidae)

A new species of intestinal coccidian is described from the weedy or common sea dragon Phyllopteryx taeniolatus housed at the New England Aquarium in Boston and at the Shedd Aquarium in Chicago, USA. Live oocysts of Eimeria phyllopterycis sp. n. are spherical, 30.9 (28.0-34.4) microm, with a thin, single-layered wall. Both a micropyle and oocyst residuum are absent and a large polar granule is sometimes present. Sporocysts are ellipsoidal and elongate, 24.3 x 10.4 (23.4-25.6 x 9.2-11.2) microm, with Stieda and substieda bodies; shape index (length/width) 2.33 (2.14-2.70). A sporocyst residuum is present, consisting of numerous granules of various sizes. Sporozoites each possess 3 refractile bodies. Preliminary evidence suggests that the coccidian may affect the health of sea dragons; however, it could not be determined whether this parasite caused significant morbidity or mortality.

Eimeria curvata n. sp.(Apicomplexa: Eimeriidae) in Columbina talpacoti and Scardafella squammata (Aves: Columbidae) from Brazil

Eimeria curvata is a new coccidian described in the doves Columbina talpacoti and Scardafella squammata from western of the State of São Paulo, Brazil. The oocysts are ovoid to ellipsoid, 18.3 (17-19) microm x 15.5 (15-17) microm, with a shape index of 1.2 (1.1-1.3). The wall is colorless, smooth and double-layered. A polar granule is present, but there is no micropyle or oocyst residuum. The sporocysts are elongate, 12.3 (11.5-13) microm x 5.8 (5.5-6) microm with a curved anterior portion and a smooth, thin, single-layered wall. The Stieda body is protuberant and nipple-like; there is no substieda body. The sporozoites lie head-to-tail in the sporocyst and contain a large refractile body at the extremities. The sporocyst residuum contains small granules uniformly distributed in the middle of the sporocyst. The prevalence of E. curvata n. sp. was 17.4% and 12.8% in C. talpacoti and S. squammata, respectively.

Two new species of coccidia (apicomplexa: Eimeriidae) from the bearded false chameleon Chamaeleolis barbatus (Sauria: polychridae) from cinco pesos, Pinar Del Río, Cuba

Parasitological examination of bearded false chameleons Chamaeleolis barbatus freshly imported from Cuba revealed the presence of 2 species of coccidia that are described as new. Oocysts of Isospora chamaeleolidis n. sp. are spherical to slightly subspherical, 16.1 (13-21) x 15.6 (13-19) microm, with a brownish and bilayered wall approximately 1.0-1.5 microm thick; outer layer markedly pitted. 0.75-1.0 microm thick. One, rarely 2, globular polar granules, 1.5 in diameter are present in the sporulated oocysts. Sporocysts are ellipsoidal, 10.8 (10-13) x 7.8 (7-9) microm, with a smooth, colorless, and unilayered sporocyst wall. Stieda body and substieda bodies are present. A sporocyst residuum is present, consisting of small granules of irregular size scattered among the sporozoites. Oocysts of Eimeria chamaeleolidisbarbati n. sp. are broadly oval, 19.0 (17-21) x 15.7 (15-17) microm, with a bilayered, colorless oocyst wall approximately 0.75 thick; outer layer of oocyst wall is smooth, 0.5 microm thick. One or 2, rarely 4, globular, irregular polar granules, approximately 1.5 microm in diameter, are present in sporulated oocysts. Sporocysts are broadly oval, 7.4 (7-8.5) x 6.1 (5.5-7) microm, with a smooth, colorless, and unilayered sporocyst wall, composed of 2 valves joined by suture; Stieda body and substieda bodies are absent.

Course of the endogenous developmental phase of selected Eimeria species in pheasants

The localization and duration of developmental stages of Eimeria colchici and Eimeria duodenalis were studied histologically. The prepatent period of the most pathogenic species from the caeca of pheasants--Eimeria colchici--was 6 days. The patent period began on the 7th day and finished on the 11th day post-infection with the maximum production of oocysts on days 8-9. In the case of Eimeria duodenalis the prepatent period was shorter--4 days, and the duration of the patent period was 3-4 days without a significant increase in oocyst production.

Eimeria peltocephali n. sp., (Apicomplexa:Eimeriidae) from the freshwater turtle Peltocephalus dumerilianus (Chelonia:Pelomusidae) and Eimeria molossi n. sp., from the bat, Molossus ater (Mammalia:Chiroptera)

The oocyst is described of Eimeria peltocephali n.sp. from faeces of the freshwater turtle Peltocephalus dumerilianus from Barcelos, State of Amazonas, Brazil. Sporulation is exogenous and fully developed oocysts are elongate, ellipsoidal or cylindrical, frequently curved to a banana-shape, 54.4 x 19.1 (37.5-68.7 x 18.7-20.0 microns), shape-index 2.8 (1.8-3.9). The oocyst wall is a single thin, colourless layer about 1 micron thick, with no micropyle. There is a bulky oocyst residuum, at first spherical to ellipsoidal, 19 x 16 (16.2-26.2 x 16-21.5 microns), but becoming dispersed on maturation. There are no polar bodies. The sporocysts, 19.1 x 6.8 (17.5-21.2 x 6.2-7.5 microns), shape-index 2.8 (2.3-3.2), are usually disposed in pairs at each end of the oocyst, and bear an inconspicuous Stieda body in the form of a flat cap. The sporozoites are elongate and slightly curved around the residuum. No refractile bodies were seen. Eimeria molossi n.sp., is described from the molossid bat Molossus ater. Sporulation is exogenous and the mature oocysts are predominantly broadly ellipsoidal, 23.4 x 17.5 (18-30 x 15-22.5 microns), shape-index 1.3 (1-1.6). The oocyst wall is about 2 microns thick, and of three layers: an inner thin, colourless one and two outer layers which are thicker, yellowish-brown, prominently striated and in close apposition. There is no micropyle or oocyst residuum, but one and occasionally two polar bodies are usually present. Sporocysts are ellipsoidal, 10.2 x 7.5 (10-12.5 x 7.5 microns), shape-index 1.4 (1.3-1.7) with an inconspicuous Stieda body. Endogenous stages are described in the epithelial cells of the small intestine.

Quantitative characterization, classification and reconstruction of oocyst shapes of Eimeria species from cattle

This study reports on morphological variability of Eimeria species, which may be given either by drawings or as quantitative data. The drawings may be used to facilitate identification by eye of 'unknown' Eimeria specimens, whereas quantitative data may serve as a reference set for identification by multivariate statistical techniques. The morphology of 810 Eimeria specimens was defined in binary (b/w) digital images by pixels of their oocyst outline. A Fourier transform of pixel positions yielded size and shape features. To classify coccidia, the quantitative data were employed in an agglomerative clustering by average linkage algorithm with equal weight assigned to size and shape. An inverse Fourier transform served to reconstruct oocyst outlines, i.e. outlines of average shape and size, from mean values of features in resulting clusters. Clusters were subsequently identified based on their average morphology by comparison with drawings of species in an earlier taxonomical work. Five hundred oocyst outlines were simulated for each cluster representing a species, and shape/size variability was presented in contour diagrams. Differences in species shapes, and correspondence in length and width, were seen after reconstruction by inverse Fourier transform and comparison with earlier studies.

Two new species of Eimeria (Apicomplexa, Eimeriidae), from local chickens (Gallus domesticus) in Saudi Arabia

In this study, two new species of Eimeria parasitizing domestic fowl (Gallus domesticus) are described. Species data were recorded as follow: Eimeria jeddahensis sp. n. with ovoidal occysts 23.5-29.2 x 17.5-22.4 (25.78 +/- 0.357 x 20.32 +/- 0.33) microns, with smooth single layered wall; bilobed polar granule and micropyle present. Sporocysts elongated ovoidal 10-13.5 x 6.3-8.0 (12.03 +/- 0.135 x 7.10 +/- 0.070) microns with a thick, knob like Stieda body and residuum. Eimeria waeli sp. n. with ellipsoidal oocysts 26.5-31.0 x 23.5-27.0 (28.30 +/- 0.327 x 25.30 +/- 0.278) microns with a double-layered wall; polar granule and micropyle present. Sporocysts ovoidal 13.5-16.0 x 7.0-9.5 (14.67 +/- 0.135 x 8.32 +/- 0.162) microns with distinct Stieda body and residuum. The host bird belongs to order Galliformes.

Eimeria schmidti n. sp. (Apicomplexa: Eimeriidae) from the sandy fringe-toed lizard (Acanthodactylus schmidti) in Saudi Arabia

Eimeria schmidti n.sp. is described from the gall bladder of Acanthodactylus schmidti from Al-Thomama area in the central region of Saudi Arabia. Sporulated oocysts are ellipsoid 31.2 x 23.3 (26.9-36.4 x 21.2-26.0). Oocyst wall is smooth, greenish yellow, 1.31 (1.16-1.41) um thick and two-layered. Micropyle, polar granule and oocyst residuum are absent. Sporocysts are ellipsoid 12.6 x 9.3 (10.9-14.1 x 7.6-10.0) um. Sporocyst residuum is present. The sporocysts lack a stieda body. Sporozoites are banana shaped blunt at one end and tapered at the second end. Eimeria species from Lacertidae are compared.

Ultrastructure and cytochemistry study of Eimeria sparis (Protozoa:Apicomplexa) stages from the intestine of gilthead sea bream Sparus aurata L. (Pisces:teleostei)

The ultrastructure and cytochemistry of merogonial, gamogonial, and early sporogonial stages of Eimeria sparis in the intestine of Sparus aurata were studied. Mature stages showed the typical pellicle, which was lost in some transitional stages. An apparent unit membrane was seen in some immature stages. A parasitophorous vacuole, sometimes with membrane vesicular invaginations, was usually observed. We propose that the stages located over the epithelium and the so-called epicellular stages be termed supraepithelial stages. Endomerogony was observed in intraepithelial and supraepithelial positions. Intraepithelial stages apparently starting ectomerogony were also detected. Electron-dense granules similar to wall-forming-like bodies of types 1 and 2 were observed. Microgametes exhibited two flagella. Cytochemistry study revealed scarce polysaccharides, if any, in merogonial stages and in microgamonts. The occurrence of polysaccharides and amylopectin granules increased progressively in macrogamonts, macrogametes, zygotes, and early oocysts. Lipidic droplets were scarce of absent in merogonial stages and abundant in maturing macrogamonts. Some glycoproteins were demonstrated in certain merogonial stages.

Light microscopic description of Eimeria sparis sp. nov. and Goussia sparis sp. nov. (Protozoa:Apicomplexa) from Sparus aurata L. (Pisces: Teleostei)

Two new species of Coccidia, Eimeria sparis sp. nov. and Goussia sparis sp. nov., were found in the intestine of Sparus aurata from different culture systems of Spain. These are the first coccidian species described from this host. E. sparis is distinguished from other Eimeria spp. from Perciformes in the size and shape of the sporocysts, which measure 6-9.7 (mean = 7.78, SD = 1.33) x4-6.5 (5.3 +/- 0.92) microns, and in the Stieda-like body. Mature oocysts, spherical or subspherical, measure 9.4-14.3 (11.88 +/- 1.85) microns. G. sparis differs from other Goussia spp. from fish of the Mediterranean area in the size and shape of the oocysts and sporocysts as well as in the location. Mature oocysts measure 16-21 (17.4 +/- 1.5) x 13-18 (14.4 +/- 1.7) microns and sporocysts, 8.6-10.3 (9.5 +/- 0.5) x 5.7-7.4 (mean 6.5 +/- 0.5) microns. The different stages of merogony, gamogony, and sporogony of both species were examined at the light-microscope level in fresh material and histology specimens. Sporulation was endogenous in E. sparis and exogenous in G. sparis.

How do sporozoites of rabbit Eimeria species reach their target cells?

In all the studies performed on the invasion of the rabbit by sporozoites of 4 Eimeria species it was shown that the sporozoites first penetrate the duodenal epithelium; and then very quickly appear within the IELs of the duodenal epithelium. A few hours later they are found in IELs of their specific site of multiplication. The relationship between an "extraintestinal" route for sporozoites and the IELs homing phenomenon is therefore an exciting hypothesis.

Coccidian parasites (Apicomplexa: Eimeriidae) from two species of caimans, Caiman yacare daudin and Caiman latirostris daudin (Alligatoridae), from Paraguay

From October 1986 to January 1987, feces from 119 Caiman yacare and 12 Caiman latirostris were collected in Paraguay and later examined for coccidian oocysts; 69 of 119 (58%) samples from C. yacare and 3 of 12 (25%) samples from C. latirostris contained coccidian oocysts. Two eimerians infected C. yacare and both are described as new species. Sporulated oocysts of Eimeria paraguayensis n. sp. are ellipsoid, 34.0 x 23.6 (26-38 x 20-29) microns with sporocysts ovoid, 14.0 x 7.1 (10-19 x 6-10) microns. Sporulated oocysts of Eimeria caimani n. sp. are spheroid, 22.4 (19-29) microns with sporocysts ovoidal, 12.9 x 6.5 (8-17 x 5-8) microns. Isospora jacarei infected C. latirostris and is redescribed. Sporulated oocysts of I. jacarei are sub-spheroid, 13.2 x 12.1 (10-18 x 10-15) microns with sporocysts ellipsoid, 10.4 x 5.8 (7-13 x 4-11) microns. To date, members of the Eimeriidae found in Crocodylia include 5 species of Eimeria and 2 of Isospora including the new species described here.

Eimeria species infecting wood mice (genus Apodemus) and the transfer of two species to Mus musculus

Characteristics of four species of Eimeria isolated from Apodemus sylvaticus are described. From oocyst morphology, three are identified as E. apionodes, E. hungaryensis and E. uptoni, the fourth being unnamed. Cloning demonstrated that oocysts of E. hungaryensis were polymorphic. Previous literature relating to the taxonomy is discussed and discrepancies outlined. Species isolated from A. sylvaticus were not transmissible to Clethrionomys glareolus, but both E. hungaryensis and E. apionodes have been passaged through immunosuppressed laboratory mice, the former species more than 16 times. In both A. sylvaticus and immunosuppressed laboratory mice, endogenous development of E. hungaryensis occurred mainly in enterocytes near the tips of the villi in the first half of the small intestine, with a few parasites in the rest of the small intestine and into the large intestine. The pre-patent period was 2 days in both hosts but oocyst output was higher in the natural hosts. E. apionodes parasitized enterocytes on the sides or at the base of the villi, mainly in the last 90% of the small intestine with a few parasites in the large intestine. The pre-patent period was 7 days. Parasites, probably E. hungaryensis and E. apionodes, were also isolated from A. flavicollis.

[The observation of coccidia in swine]

The coccidia species of domestic pig and wild boar were compared and defined morphologically and the sporogony of both was examined. No difference could be detected between the coccidia species of domestic pig and wild boar. Six Eimeria and one Isospora species were found: Eimeria debliecki, E. polita, E. porci, E. scabra, E. spinosa, E. suis and Isospora suis. E porci could be found in Austria for the first time. E. cerdonis Vetterling, 1965 is a synonym of E. polita Pellérdy, 1949.

Eimeria cryptotis n. sp. (Apicomplexa: Eimeriidae) from the least shrew, Cryptotis parva (Insectivora: Soricidae), in north-central Texas

From March through November 1987, 14 least shrews, Cryptotis parva (Say), were collected in portions of north-central Texas and examined for coccidian parasites; only 1 (7.1%) was found to be passing oocysts. Eimeria cryptotis n. sp. is described herein as new and represents the only coccidian reported thus far from C. parva. Sporulated oocysts are subspherical, 16.4 x 15.3 (14-18 x 13-17) microns; shape index 1.1 (1.0-1.2) microns. A micropyle and oocyst residuum are absent, but a polar granule is present. The sporocysts are ovoid, 10.6 x 7.0 (9-11 x 6-8) microns; shape index 1.5 (1.4-1.8) microns. Stieda and substieda bodies and a sporocyst residuum are present. The sporozoites are elongate and only 2 could be observed well enough to measure (11.2 x 2.4 and 8.8 x 2.4 microns) because they are normally obscured by the sporocyst residuum. Sporozoites lack refractile bodies and contain a centrally located nucleus. The new species can be distinguished from the majority of insectivore coccidia on the basis of oocyst size.

Analysis of coccidian oocyst populations by means of flow cytometry

Flow cytometry was employed as a tool to analyze and characterize batches of oocysts from laboratory and field isolates of Eimeria spp. from chickens and to propagate sub-populations of batches of oocysts. Oocyst batches were cleaned of debris by a combination of salt flotation, washing and treatment with dilute sodium hypochlorite (1.5% aqueous). Oocyst size and shape were registered by forward-angle light scatter with the argon laser excitation set at 488 nm at 300 mW. Sub-populations of oocysts were collected by map gating and used for microscopy or for propagation. The profile of particle size was characteristic for each species. Propagation of sub-populations of oocysts of specified sizes resulted in cultures of coccidia that were pure species or nearly pure species. The small size of E. mitis caused difficulty in separation from the remaining fine debris. This technique was useful for studying the mixed isolates by bit-map gating had the same limitations as micromanipulation because of the overlapping size of Eimeria spp. Characterization is further limited by the lack of suitable size/shape standards for flow cytometry.

Coccidia (Apicomplexa: Eimeriidae) from the subterranean rodent Ctenomys opimus Wagner (Ctenomyidae) from Bolivia, South America

Of 35 tuco-tucos (Ctenomys opimus) collected in Bolivia, South America, 31 (88%) had eimerian oocysts in their feces at the time they were examined. Eighteen (58%) of the 31 infected animals were concurrently infected with 2 or 3 eimerian species. Four species of Eimeria were recovered and are described as new species based on the characteristics of sporulated oocysts. Oocysts of Eimeria granifera n. sp. were ellipsoidal, 21.1 x 17.2 (15-26 x 11-20) micron with sporocysts ovoidal, 11.3 x 7.1 (8-14 x 5-9) micron. Oocysts of Eimeria montuosi n. sp. were spheroidal, 24.2 x 22.0 (21-28 x 18-25) micron with sporocysts ovoidal, 10.5 x 7.3 (8-14 x 6-9) micron. Oocysts of Eimeria opimi n. sp. were spheroidal to subspheroidal, 24.3 x 21.8 (18-29 x 15-26) micron with sporocysts ovoidal, 11.6 x 7.6 (10-13 x 6-9) micron. Oocysts of Eimeria oruroensis n. sp. were spheroidal to subspheroidal, 27.3 x 23.6 (23-32 x 20-28) micron with sporocysts ovoidal, 13.2 x 8.6 (10-16 x 8-11) micron.

Eimeria saudiensis n. sp. (Apicomplexa: Eimeriidae) from the Arabian oryx (Oryx leucoryx) in Saudi Arabia

Oocysts of Eimeria saudiensis n. sp. (Apicomplexa: Eimeriidae) are described from the feces of the Arabian oryx, Oryx leucoryx, from the Riyadh Zoo, Saudi Arabia. The oocysts were ellipsoidal or slightly ovoid, 31.2 x 24.5 (24.3-36.5 x 20.0-27.6) micron with a bilayered wall about 1.7 micron thick. The micropyle was covered by a dome-shaped cap. The oocyst residuum was absent, but tiny polar granules were present. The sporocysts were elongate ovoid, 14.3 x 7.2 (11.5-18.5 x 6.0-9.0) micron, had a Stieda body, but lacked a substiedal body. The sporocyst residuum was present, composed of numerous small granules. The sporozoites were elongate club-shaped, and contained two prominent refractile bodies.

Two new species of Eimeria from peacocks (Pavo cristatus) in Saudi Arabia

Fifteen fecal samples from peacocks (Pavo cristatus) in Saudi Arabia contained oocysts of Eimeria riyadhae n. sp. in two peacocks and oocysts of E. arabica n. sp. in one peacock. Sporulated oocysts of Eimeria riyadhae are ellipsoidal, 27-30.5 x 20.5-25 (28.8 +/- 1.3 x 22.4 +/- 1.6) micron, with a two-layered wall and bilobed polar body, but without a micropyle or residuum. The sporocysts are ovoid, 11-14.5 x 6.5-8 (13.2 +/- 1.2 x 7.2 +/- 0.6) micron with a thick, knob-like Stieda body and a residuum. Sporulated oocysts of Eimeria arabica are spheroidal, 17.5-21.5 x 17.5-21.5 (19.2 +/- 1.6 x 19.2 +/- 1.6) micron, with a two-layered wall and two refractile polar bodies, but without a micropyle or residuum. The sporocyts are elongate ovoid, 9.5-12 x 4-6.5 (11.2 +/- 0.9 x 5.5 +/- 0.88), with a small crescent-shaped Stieda body. The host bird belongs to the order Galliformis.

Two new species of coccidia (Apicomplexa: Eimeriidae) from Madagascar Gekkonids

Two new species of coccidia (Apicomplexa: Eimeriidae) are described from the Madagascar giant day gecko, Phelsuma madagascariensis grandis, and the Golddust day gecko, P. laticauda. Both species of coccidia were found to infect the anterior one-half of the small intestine. Oocysts of Eimeria brygooi n. sp. are spherical or subspherical, 23.0 X 21.3 (18.8-25.2 X 16.4-23.2)micron; shape index (L/W) 1.1 (1.0-1.2). A micropyle, oocyst residuum, and polar granule are absent. Sporocysts are ovoid, 9.2 X 7.9 (8.0-10.0 X 7.2-8.8) micron; shape index 1.2 (1.0-1.3), with a Goussia-type suture; Stieda and substieda bodies are absent. A sporocyst residuum is present, 4.2 X 3.0 (3.2-6.4 X 2.4-4.0) micron. Sporozoites are elongate, with anterior and posterior refractile bodies. This coccidian was found to infect five of six (83%) P. m. grandis and one of five (20%) P. laticauda examined. Oocysts of Isospora gekkonis n. sp. are spherical or subspherical, 24.2 X 22.0 (21.6-26.4 X 20.0-23.6) micron; shape index 1.1 (1.0-1.2). A micropyle and oocyst residuum are absent; polar granule present. Sporocysts are ovoid, 12.2 X 9.4 (11.2-12.8 X 8.4-10.0) micron, with Stieda and substieda bodies; shape index 1.3 (1.2-1.4). A sporocyst residuum is present, either compact, 5.1 X 4.2 (4.0-7.2 X 3.2-5.6) micron or diffuse. Sporozoites are elongate, with anterior and posterior refractile bodies. Isospora gekkonis was found in two of six (33%) P. m. grandis and one of five (20%) P. laticauda. In addition, oocysts of Cryptosporidium sp. were found in the cloacas of two of six (33%) necropsied P. m. grandis.

Eimeria tahamensis N. sp. (Apicomplexa: Eimeriidae) from the Arabian quail (Coturnix delegorguei arabica)

Eimeria tahamensis n. sp. is described from the harlequin quail (Coturnix delegorguei arabica) from Tahama, Saudi Arabia. The sporulated oocysts of E. tahamensis n. sp. are ellipsoid, 36.5-42 X 25.5-29 (41.2 +/- 1.34 X 28.4 +/- 0.81) micron, with a thick two-layered wall and one polar granule but without a micropyle or an oocyst residuum. The sporocysts are ovoid, 14-16 X 9-11.5 (15.3 +/- 0.7 X 10.8 +/- 0.64) micron, with a knob-like Stieda body and sporocyst residuum, but without a substiedal body. The sporozoites are often located transversely at the two ends of the sporocysts. The host bird belongs to the order Galliformes.

Coccidian parasites (Apicomplexa: Eimeriidae) from insectivores. III. Seven new species in shrews (Soricidae: Soricinae) from Canada, Japan, and the United States

Since May 1979, 458 shrews (Blarina sp. and Sorex spp.) representing 20 species collected in Canada, Japan, and the United States were examined for coccidia; 110 (24%) had oocysts in their feces, including 8 of 21 (38%) B. brevicauda from Massachusetts, Ohio, Pennsylvania, and Vermont; 2 of 7 (29%) S. caecutiens from Hokkaido and Honshu; 14 of 63 (22%) S. cinereus from Colorado, New Mexico, Pennsylvania, Vermont, Manitoba, and Ontario; 3 of 7 (43%) S. fontinalis from Pennsylvania; 11 of 16 (69%) S. fumeus from Massachusetts, Minnesota, Pennsylvania, Vermont, and Ontario; 1 of 4 (25%) S. haydeni from Minnesota; 6 of 8 (75%) S. longirostris from Florida and Virginia; 1 of 2 (50%) S. ornatus from California; 5 of 12 (42%) S. pacificus from California and Oregon; 13 of 41 (32%) S. palustris from California, Colorado, and New Mexico; 1 of 2 (50%) S. tenellus from California; 11 of 105 (10%) S. trowbridgii from California, Oregon, and Washington; 10 of 48 (21%) S. unguiculatus from Hokkaido; and 24 of 112 (21%) S. vagrans from Arizona, California, Colorado, New Mexico, Oregon, and Washington. The following coccidians were identified from infected shrews: Eimeria brevicauda n. sp. from B. brevicauda; Eimeria fumeus n. sp. from S. fumeus, S. pacificus, S. unguiculatus, and S. vagrans; Eimeria inyoni n. sp. from S. tenellus; Eimeria palustris n. sp. from S. cinereus, S. fontinalis, S. fumeus, S. haydeni, S. longirostris, S. ornatus, S. pacificus, S. palustris, S. tenellus, S. trowbridgii, and S. vagrans; Eimeria vagrantis n. sp. from S. fumeus, S. trowbridgii, and S. vagrans; Isospora brevicauda n. sp. from B. brevicauda; and Isospora palustris n. sp. from S. pacificus, S. palustris, S. trowbridgii, S. unguiculatus, and S. vagrans. The world literature on coccidian parasites of shrews (16 eimerians and 3 isosporans exclusive of the 7 new species described here) is reviewed.

Coccidia (Apicomplexa: Eimeriidae) from sciurid rodents (Eutamias, Sciurus, Tamiasciurus spp.) from the western United States and northern Mexico with description of two new species

Since May 1979, 190 rodents in the family Sciuridae, representing three genera and nine species, have been collected in the western United States and northern Mexico and examined for coccidia; 71 (37%) had coccidian oocysts in their feces. These included 2 of 12 (17%) Eutamias canipes; 7 of 12 (58%) E. dorsalis; 18 of 50 (36%) E. merriami; 33 of 96 (34%) E. obscurus; 3 of 4 (75%) E. townsendii; 3 of 9 (33%) Sciurus aberti; 1 of 1 S. griseus; 1 of 1 Tamiasciurus hudsonicus mogollonensis; and 3 of 5 (60%) T. mearnsi. The following coccidians were identified from infected rodents: Eimeria cochisensis n. sp. and Eimeria dorsalis n. sp. from E. canipes, E. cochisensis, E. dorsalis, and E. tamiasciuri from E. dorsalis, E. dorsalis and E. tamiasciuri from E. merriami; E. cochisensis, E. dorsalis, E. tamiasciuri, and E. wisconsinensis from E. obscurus; E. cochisensis and E. dorsalis from E. townsendii; E. ontarioensis and E. tamiasciuri from S. aberti; E. tamiasciuri from S. griseus; E. tamiasciuri and E. toddi from T. h. mogollonensis; and E. tamiasciuri from T. mearnsi. Sporulated oocysts of Eimeria dorsalis n. sp. were ovoid, 21.9 x 16.8 (17-24 x 14-20) micrometer with sporocysts ovoid, 11.5 x 6.9 (10-14 x 6-8) micrometer. Sporulated oocysts of Eimeria cochisensis n. sp. were spheroid to subspheroid, 16.7 x 15.3 (15-18 x 14-17) micrometer, with sporocysts ovoid, 8.4 x 5.6 (6-11 x 4-7) micrometer. Fifty-five of 71 (77%) infected hosts had oocysts of only one eimerian species in their feces at the time they were examined. One eimerian, E. tamiasciuri, was found in seven of nine host species in three genera. A list is provided of all eimerians (22, including the species described here) that have been described in the literature from Eutamias, Sciurus, and Tamiasciurus spp.

Coccidian parasites (Apicomplexa: Eimeriidae) from insectivores. II. Six new species from Japanese shrew moles (Talpidae)

Thirty-eight of 51 (74.5%) shrew moles collected in Japan were infected with from one to four species of Eimeria and/or Isospora including six of six Dymecodon pilirostris and 32 of 45 (71.1%) Urotrichus talpoides. Four eimerians and two isosporans were identified and all are described as new species. Sporulated oocysts of Eimeria amorphospora n. sp. were subspheroid/ellipsoid, 21.1 x 17.9 (18-25 x 16-21) micrometers. Sporocysts were amorphous, gelatinoid envelopes greater than or equal to 20.3 x 7.5 (17-24 x 7-9) micrometers. Sporozoites were enclosed together within a membrane in each sporocyst. This species was found in 9 of 45 (20%) U. talpoides. Sporulated oocysts of Eimeria gonocilia n. sp. were subspheroid/ellipsoid, 28.8 x 24.4 (25-30 x 21-28) micrometers; a highly ornate outer oocyst wall gave the appearance of a ciliated ball. Sporocysts ovoid, pointed at both ends, were 17.0 x 9.9 (15-19 x 7-11) micrometers; this species was found in 4 of 45 (8.9%) U. talpoides. Sporulated oocysts of Eimeria talpoidei n. sp. were asymmetrical ovoid, 20.6 x 13.3 (18-23 x 12-15) micrometers, with sporocysts lacrimiform, 12.0 x 5.8 (10-14 x 5-7) micrometers. This species was found in 7 of 45 (15.6%) U. talpoides. Sporulated oocysts of Eimeria honshuensis n. sp. were ellipsoid, 15.5 x 11.4 (13-18 x 10-13) micrometers, with sporocysts ovoid, 9.1 x 5.2 (8-10 x 4-6) micrometers. This species was found in 10 of 45 (22.2%) U. talpoides and in 5 of 6 (83.3%) D. pilirostris. sporulated oocysts of Isospora dymecodi n. sp. were subspheroid/ellipsoid, 15.8 x 12.6 (13-17 x 11-13) micrometers, with sporocysts ovoid, 9.1 x 5.2 (8-10 x 4-6) micrometers. This species was found in 10 of 45 (22.2%) U. talpoides and in 5 of 6 (83.3%) D. pilirostris. Sporulated oocysts of Isospora dymecodi n. sp. were subspheroid/ellipsoid, 15.8 x 12.6 (13-17 x 11-13) micrometers, with sporocysts ellipsoid, 10.9 x 6.9 (10-13 x 6-8). This species was found in six of six D. pilirostris. Sporulated oocysts of Isospora urotrichi n. sp. were spheroid/subspheroid, 13.4 x 12.4 (11-16 x 9-14) micrometers, with sporocysts ovoid, 9.2 x 6.3 (8-11 x 5-7) micrometers. This species was found in 27 of 45 (60%) U. Talpoides. Only 14 of 38 (36.8%) infected hosts (one D. pilirostris, 13 U. talpoides) were seen to be naturally infected with only one coccidian species when sampled.

Eimerians from different karyotypes of the Japanese wood mouse (Apodemus spp.), with descriptions of two new species and a redescription of Eimeria montgomeryae Lewis and Ball, 1983

Examination of 131 wood mice (Apodemus spp.) representing 2 species and 6 subspecies collected from the Japanese islands of Hokkaido, Honshu, Kyushu, and Tsushima showed that 70 mice (53%) had coccidian oocysts in their feces. These included 21 of 42 (50%) Apodemus argenteus argenteus; 7 of 14 (50%) Apodemus argenteus hokkaidi; 2 of 3 (67%) Apodemus argenteus sagax; 3 of 9 (33%) Apodemus speciosus ainu; 36 of 61 (59%) Apodemus speciosus speciosus; and 1 of 2 (50%) Apodemus speciosus tusimaensis. Four distinct coccidians were identified: Eimeria argenteus n. sp. from A. a. argenteus, A. a. hokkaidi, A. a. sagax, and A. s. speciosus; Eimeria inuyamensis n. sp. from A. a. argenteus, A. s. speciosus, and A. s. tusimaensis; Eimeria montgomeryae Lewis and Ball, 1983, from A. a. argenteus, A. a. hokkaidi, A. a. sagax, A. s. ainu, and A. s. speciosus; and Eimeria uptoni Lewis and Ball, 1983, from A. a. argenteus, A. a. hokkaidi, and A. s. speciosus. Standard karyotypes were prepared from selected specimens of each host subspecies. All 3 subspecies of A. argenteus and A. s. tusimaensis have a 2n = 46; A. s. ainu, from Hokkaido, has a 2n = 48; and A. s. speciosus has at least 2 chromosomal races, 1 on northern (2n = 48) and 1 on southern (2n = 46) Honshu. Both chromosomal races of A. s. speciosus, as well as the other subspecies of Apodemus examined, shared their coccidian parasites freely.

Coccidian parasites (Apicomplexa: Eimeriidae) from insectivores: new species from shrew moles (Talpidae) in the United States

All of 18 shrew moles, Neurotrichus gibbsii, collected in Oregon and Washington were infected with one or more species of coccidia. Three eimerians and one isosporan were identified and described as new species. Sporulated oocysts of Eimeria heterocapita n. sp. were subspheroid to ellipsoid, 25.5 X 21.4 (23-27 X 18-23) micron. A membranous, cap-like structure was present at one pole of the oocyst, but a micropyle, oocyst residuum, and polar body were absent. Ovoid sporocysts were 13.6 X 10.0 (12-15 X 9-11) micron; a compact sporocyst residuum was present, but Stieda, sub-, and parastieda bodies were absent. This species was found in 2 of 18 (11%) hosts. Sporulated oocysts of Eimeria neurotrichi n. sp. were ovoid, 17.6 X 13.6 (16-20 X 11-16) micron; micropyle and oocyst residuum were absent, but a polar body was present. Ovoid sporocysts were 10.7 X 5.5 (9-12 X 5-6) micron; Stieda body and sporocyst residuum were present, but sub- and parastieda bodies were absent. This species was found in 2 of 18 (11%) hosts. Sporulated oocysts of Eimeria parastiedica n. sp. were subspheroid, 27.4 X 25.5 (25-30 X 22-28) micron; micropyle, oocyst residuum, and polar body were absent. Ovoid sporocysts, pointed at both ends, were 18.3 X 10.4 (16-20 X 9-11) micron; Stieda, sub-, and parastieda bodies were present as was a sporocyst residuum. This species was found in 2 of 18 (11%) hosts.(ABSTRACT TRUNCATED AT 250 WORDS)

Eimeria species (Apicomplexa: Eimeriidae) infecting Peromyscus rodents in the southwestern United States and northern Mexico with description of a new species

Of 198 deermice (Peromyscus spp) collected from various localities in the southwestern United States and northern Mexico, 106 (54%) had eimerian oocysts in their feces when examined. These included 50 of 106 (47%) Peromyscus truei, 34 of 54 (63%) Peromyscus maniculatus, 4 of 17 (24%) Peromyscus leucopus, and 18 of 21 (86%) Peromyscus eremicus. The following Eimeria were identified from infected mice: Eimeria arizonensis and Eimeria langebarteli from P. truei; E. arizonensis, Eimeria peromysci, and Eimeria delicata from P. maniculatus; E. arizonensis and Eimeria lachrymalis n. sp. from P. eremicus; and E. langebarteli from P. leucopus. Of the 106 Peromyscus found positive for Eimeria, 97 (91.5%) harbored only a single eimerian species at the time of examination. Sporulated oocysts of E. lachrymalis n. sp. were ellipsoid, 27-35 X 17-21 (30.8 +/- 1.7 X 19.1-0.9) micron, possessed a smooth wall and one polar granule, but lacked a micropyle and an oocyst residuum. Sporocysts were teardrop-shaped, 9-13 X 6-10 (10.9 +/- 0.9 X 7.9 +/- 0.5) micron, and had a Stieda body and sporocyst residuum, but no substieda body. Prepatent periods in experimental infections were 3-6 days after inoculation (DAI) for E. arizonensis (hosts: P. eremicus, P. maniculatus, P. truei); 4-5 DAI for E. peromysci (host: P. maniculatus); 6-9 DAI for E. langebarteli (hosts: P. truei, P. leucopus); and 8-10 DAI for E. lachrymalis (host: P. eremicus). Patency in these infections lasted 6-11 days for E. arizonensis, 5-10 days for E. peromysci, 14-40+ days for E. langebarteli, and 19-50+ days for E. lachrymalis. Eimeria lachrymalis appears to produce occult infections in P. eremicus that can be reactivated upon inoculation of the host with E. arizonensis.

Eimeria ladronensis n. sp. and E. albigulae (Apicomplexa: Eimeriidae) from the woodrat, Neotoma albigula (Rodentia: Cricetidae)

Of 50 white-throated woodrats (Neotoma albigula) collected from Socorro Co., New Mexico, 21 (42%) had eimerian oocysts in their feces when examined. Of the 21 Neotoma found positive for Eimeria, 19 (90%) harbored a single eimerian species at time of examination. Eimeria albigulae Levine, Ivens & Kruidenier, 1957, was found in 18 (86%), and E. ladronensis n. sp. was found in five (24%) infected woodrats. Sporulated oocysts of E. ladronensis are ellipsoidal, 19-25 X 13-15 (21.4 +/- 1.3 X 14.1 +/- 1.1) micron, have a smooth wall and one or two polar granules, but lack a micropyle and an oocyst residuum. Sporocysts are tapered at one end, 7-10 X 6-7 (8.5 +/- 0.7 X 6.5 +/- 0.3) micron, and have a Stieda body and sporocyst residuum, but no substieda body. Prepatent periods for E. albigulae and E. ladronensis n. sp. are 5-6 and 8-9 days, respectively; patent periods are 7-18 and approximately 11 days, respectively.

Host specificity in eimerian coccidia: development of Eimeria vermiformis of the mouse, Mus musculus, in Rattus norvegicus

The ability of Eimeria vermiformis, a coccidium which normally parasitizes the mouse, to develop in rats was investigated. The Rowett strain (Lac: RNU) rats were euthymic (rnu/+), treated or untreated with cortisone acetate, and athymic (rnu/rnu). E. vermiformis completed its development only in rnu/rnu rats, which passed small numbers of oocysts capable of sporulating and infecting C57BL/6 mice. In the rnu/+ rats, irrespective of cortisone treatment, development appeared to terminate with the completion of the asexual (schizogonic) stages since no gametocytes were recognized in the tissues and no oocysts were detected in the faeces. The findings are discussed with reference to the factors which govern host specificity.