Coccidia from the Tiger Salamander, Ambystoma tigrinum, in Northeastern Colorado and in Northern New Mexico

SYNOPSIS. Oocysts of Eimeria ambystomae Saxe, 1955, Eimeria microcapi sp. n., and Eimeria urodela sp. n. are described from the tiger salamander, Ambystoma tigrinum , collected in Colorado and New Mexico. The oocysts of E. ambystomae are ellipsoid, 29.8 × 17.3 (24–38 × 15–25) μm, and the sporocysts lanceolate, 22.6 × 5.4 (16–27 × 5–7) μm. Oocyst and sporocyst residua are present, but not a polar granule and a micropyle. The oocysts and sporocysts of E. microcapi are ellipsoid, measuring respectively 38.1 × 25.3 (35-41 × 23-26) μm and 18.1 × 7.4 (16-19 × 6–8) μm. Oocyst and sporocyst residua, a micropyle (mean 3 μm), and a distinct micropyle cap (2 μm high) are present, but not a polar granule. The oocysts of E. urodela are spheroid, 22.2 (14-26) μm, and the sporocysts lanceolate, 16.3 × 5.8 (12-19 × 4-7) μm. Oocyst and sporocyst residua are present, but a polar granule and a micropyle are absent.     

Eimeria galateai sp. n. from the Paradise Kingfisher, and Eimeria duncani sp. n. from the Sacred Kingfisher in Papua New Guinea

SYNOPSIS. Eimeria galateai sp. n. from the paradise kingfisher ( Tanysiptera galatea Gray) and Eimeria duncani sp. n. from the sacred kingfisher ( Halcyon sancta Vigors & Horsfield) have been described from Papua New Guinea. Four of 11 paradise kingfishers were infected with E. galateai oocysts, measuring 13 (11–16) × 9 (8–11) μm. The oocysts were ovoid with nipple-like protrusion at one pole. Micropyle and polar granule were absent, while oocyst residuum (5 × 4 μm) was present. Sporocysts, measuring 5 (4–6) × 2 μm, were elongate-ovoid, and had a distinct convex Stieda body; the sporocyst residuum was absent. Two of 9 sacred kingfishers were infected with ovoid-truncated, 22 (19–25) × 16 (12–18) μm oocysts of E. duncani . Polar granule (5 × 2) was present in the oocysts, but there was no micropyle or oocyst residuum. Sporocysts were ovoid, measuring 9 (8–10) × 5 (4–6) μm, with a prominent Stieda body, and granular sporocyst residuum. Eimeria galateai and E. duncani are the first species of this genus to be described from birds of the order Coraciiformes.     

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.     

Eimeria zapi sp. n. from the Meadow Jumping Mouse, Zapus hudsonius Zimmerman in Southwestern Michigan

SYNOPSIS Four of 5 meadow jumping mice ( Zapus hudsonius ) captured had in their feces a previously undescribed species of Eimeria which is named Eimeria zapi sp. n. The sporulated oocysts measured 21.7 (19.5–24.0) × 20.3 (17.5–23.0) μm. The single-layered oocyst wall was 1.5 μm thick, rough, pitted and appeared clear-to-amber. Usually 2 polar granules could be seen. An oocyst residuum was not observed. Each sporocyst averaged 16.0 (12.5–18.0) × 9.7 (7.5–11.5) μm. A substiedal body was present. The sporocyst residuum consisted of a membrane-enclosed packet of 15 to 20 granules. This is the first species of Eimeria to be described from the genus Zapus.     

Isospora atrata N. Sp. (Apicomplexa, Eimeriidae): a New Coccidium Isolated from Carduelis atrata (Passeriformes, Fringillidae)

ABSTRACT Large numbers of coccidian oocysts belonging to the genus Isospora were obtained from the intestinal contents of 98 Carduelis atrata imported into Italy from South America during the months of August through December 1994. The oocysts are sub-spherical and average 21 × 20.3 μm (19.4–23.5 μm × 18.5–22 μm), have a bilayered wall, and an oval polar granule (rarely two). The sporocysts are elliptical and measure 18.8 μm × 10.3 μm (17.5–18.94 μm × 9.5–11.0 μm). The Stieda body protrudes slightly from the end of the sporocyst. A large sporocyst residuum is present, consisting of many granules that may be in a compact mass or scattered. Since this Isospora sp.does not resemble any other species of Isospora previously described from birds of the genus Carduelis , it has been named Isospora atrata n. sp. after the host. Disseminated asexual stages were found in mononuclear cells derived from formalin-fixed post mortem material, suggesting this coccidian may represent an Atoxoplasma -like parasite. Four coccidia-free Serinus canarius L. cohabitated for a long period (4 mo) with infected C. atrata but oocysts were never found in the stool of these birds.     

Eimeria urosauris n. sp., a Coccidium from the Lizard Urosaurus graciosus Hollowell, in California

SYNOPSIS. A new species of coccidium is described: Eimeria urosauris n. sp., in the gall bladder of the lizard Urosaurus graciosus Hollowell, from the Mojave Desert in California. The oocyst of E. urosauris is smooth, bilaminar, nearly cylindrical, with long borders only slightly convex, ends rounded and very nearly hemispherical. It is usually 32 × 20 μ, and its length/width ratio is 1.6. It contains 4 ellipsoid sporocysts, each 10.5 × 9 μ, for which 1/w is 1.17. Each sporocyst contains 2 tapered bent sporozoites with rounded ends, 11 μ long, 4 μ in diameter at the larger end, and 1.5 μ in diameter at the smaller end. Each sporocyst also contains a central granular sporocyst residuum 3.5 μ in diameter. The oocyst lacks a micropyle and oocyst residuum, and there is no Stieda body on the sporocyst. Sporulation time is 6–10 hr. Endogenous development, with reinfection by liberated sporozoites, occurs in the epithelial lining of the gall bladder. E. urosauris is compared to other morphologically similar lacertilian eimerias with which it might be confused.     

New Eimeriid Coccidia from the Canarian Lizard, Gallotia galloti Oudart, 1839

One species of Eimeria and one species of Isospora have been discovered in several specimens of the Canarian lizard, Gallotia galloti , collected on Tenerife, Canary Islands, and are described herein as new. The oocysts of Eimeria gallotiae n. sp. are elongate-ellipsoidal and measure 30.6 (29.1–32.6) by 16.0 (14.0–17.9) μm. Micropyle, oocyst residuum, and polar granule are absent. Oocysts each contain four ellipsoidal sporocysts measuring 14.6 (12.2–17.3) by 9.2 (8.2–11.2) μm. Sporocysts have sporocyst residuum but not a Stieda body. The majority of oocysts are fully sporulated when shed. Few oocysts are excreted unsporulated or in the beginning phase of sporulation. The oocysts of Isopora gallotiae n. sp. are spherical and 16.5 (15.3–17.6) μm in diameter. Micropyle, oocyst residuum, and polar granule are absent. Each oocyst has two lemon-shaped sporocysts, 11.5 (10.2–12.2) by 7.3 (6.6–8.2) μm, which take up almost the entire space of the oocyst. A sporocyst residuum is present as well as a knob-like Stieda body and a substieda body. Most oocysts are in the beginning phase of sporulation when excreted and have two spherical sporoblasts. Sporulation is completed within 24 to 28 h at 21 ± 2°C.     

Two New Species of Isospora from the Desert Skink (Chalchides ocellatus) from the Egyptian Desert

Isospora chalchidis n. sp. and Isospora eimanae n. sp. were isolated from the desert skink, Chalchides ocellatus , order Squamata, from Egypt. Sporulated oocysts of I. chalchidis n. sp. were spheroidal 19 × 19 (18–20.5 × 18–20.5) μm with a 2–layered walled. Oocysts lacked a micropyle and residuum and few polar granules were present. Sporocysts were lemon-shaped 12.2 × 6.5 (9.5–13 × 5–8) μm with a Stieda body and sporocyst residuum but without a substiedal body. Isospora eimanae n. sp. were spheroidal 18.5 × 18.5 (17–19.5 × 17–19.5) μm with a 2–layered wall. There were oocysts without residuum or polar granule, but with small micropyle at 1 end. Sporocysts were ovoid 12 × 8.5(11–13 × 7.5–9) μm with a small Stieda body and sporocyst residuum but without a substiedal body.     

The Structure of the Oocyst and the Excystation Process of Isospora marquardti sp. n. from the Colorado pika, Ochotona princeps

SYNOPSIS. Oocysts of Isospora marquardti sp. n. from the Colorado pika, Ochotona princeps , have spheroid oocysts, 30.5 (23–36) μm in diameter, and ovoid sporocysts, measuring 19.3 × 12.0 (17–22 × 10–14) μm. A polar body, 2 × 4 μm, a spheroid sporocyst residuum (8.3 μm in diameter), a Stieda body, and a distinct substiedal body (3 × 3 μm) are present. A micropyle and an oocyst residuum are absent. Excysted sporozoites, averaging 3.0 × 18.5 (2–4 × 15–20) μm, contain 2 refractile globules, 1 on each side of the nucleus with a prominent nucleolus.
The sporozoite excystation process using a trypsin-sodium taurocholate fluid is described.     

Isospora petrochelidon sp. n. (Protozoa: Eimeriidae) from the Cliff Swallow, Petrochelidon pyrrhonota

SYNOPSIS. Isospora petrochelidon sp. n. (Protozoa: Eimeriidae) is described from the cliff swallow, Petrochelidon pyrrhonota , from Douglas County, Colorado. Oocysts were passed primarily between 4 and 9 p.m. Sporogony was completed by 24 hr in 3% aqueous potassium dichromate at 21–28 C. The ellipsoid to ovoid oocysts averaged 25.2 × 22.2 μm. The oocyst wall was smooth, colorless, and single-layered. The 2 polar granules were disc-shaped, each adjoining a sporocyst. The lemon-shaped sporocysts averaged 18.4 × 10.8 μm. There was no membrane enclosing the sporocyst residuum and sporozoites. Two fledgling Isospora -free swallows fed sporulated oocysts began passing them on day 4 and died with massive infections on day 5. Data from these birds indicate that schizogony occurred during nighttime hours, gametogony during the day. Endogeny was found throughout the intestine distal to the gizzard, with schizogony confined to the convoluted glands of the subvillar mucosa and gametogony to the villar epithelium. Sporocysts released from mechanically ruptured oocysts excysted in 2% pancreatin within 5 min. Sporulated oocysts fed to a pigeon squab, duckling and cockerel produced no infections.     

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.     

Isospora elmahalensis n. sp. (Apicomplexa, Eimeriidae), a Parasite of the White-Cheeked Bulbul (Pycnonotus leucogenys) in Saudi Arabia

Isospora elmahalensis n. sp. is described from the Saudi Arabian bird, Pycnonotus leucogenys , from the Elmahala valley. Sporulated oocysts of I. elmahalensis were spherical or nearly subspherical, 19.5–22.5 × 18.5–20 (21.34 ± 0.4 × 19.06 ± 0.5) μm. Oocysts lacked a micropyle, residuum, and polar granule. Sporocysts were ovoid, 14–17.5 × 7–12 (16.08 ± 1.05 × 9.9 ± 1.55) μm, and had a Stieda body and sporocyst residuum, but lacked a substiedal body. Sporozoites were elongated with a clear globule at one end. The host bird belongs to the order Passeriformes.     

Eimeria tarentolae n. sp. from the Moorish Gecko, Tarentola mauritanica

ABSTRACT. A new species of Eimeria from the Moorish gecko, Tarentola mauritanica , of Minorca, Spain, is described. Oocysts of Eimeria tarentolae are ellipsoidal and measure 17.8 (17.6–18.7) μm by 13.5 (12.9–14.0) μm. Micropyle, oocyst residuum, and polar granule are absent. Each oocyst contains four spherical to slightly subspherical sporocysts 6.8 (6.4–7.0) μm in diameter. A sporocyst residuum is present, while a Stieda body is lacking. Sporulation is completed within 24–32 h at 21 ± 2°C.     

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 times 24.5 (24.3–36.5 times 20.0–27.6) μm with a bilayered wall about 1.7 μm 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 times 7.2 (11.5–18.5 times 6.0–9.0) μm, 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.     

Coccidian Parasites of Intertidal Fishes from Wales: Systematics, Development, and Cytochemistry

SYNOPSIS. Examination of littoral fish Blennius pholis and Cottus bubalis caught at Aberystwyth and Porth Cwyfan, Wales. U.K., revealed 2 species of coccidia.
Eimeria dingleyi sp. n. Oocysts spherical (16.1–19.2) to subspherical (13.9–14.2 × 18.8–20.0) μm, with thin walls; sporulation outside the host to produce ellipsoid sporocysts; endogenous phases in epithelial cells throughout intestine; 26 of 58 B. pholis infected.
Eimeria variabilis (Thélohan) Reichenow. Oocysts spherical (11.9–14.6) to subspherical (9.2–10.9 × 13.9–14.3) μm; sporulation in lining of pyloric ceca and rectum; previously unrecorded schizonts and gametocytes present; 21 of 25 C. bubalis infected.
Electron microscopy revealed that the oocyst wall of E. variabilis consists of a thin membrane whereas the sporocyst wall is thick and 3-layered. Typical oocyst wall-forming bodies were absent from the macrogamete. Cytochemical tests on the endogenous stages of E. dingleyi and E. variabilis indicated that in general they resembled other coccidia in their chemical constitution.     

Effects of exogenous interleukin-1β on primary sporocysts of Schistosoma mansoni (Trematoda) incubated with plasma and hemocytes from schistosome-susceptible and resistant Biomphalaria glabrata (Gastropoda)

Abstract. The cytokine interleukin-1β (IL-1β) mediates interactions of immune and inflammatory cells in mammals. Previous reports also have linked plasma (cell-free hemolymph) levels of IL-1β in the snail Biomphalaria glabrata to resistance against Schistosoma mansoni . In the present study, fluorescent probes were used to study larval schistosome and snail hemocyte viability during in vitro encounters. Hemolymph (plasma and hemocytes) from schistosome-susceptible (M-line) and resistant (13–16-R1) B. glabrata was added to sporocysts of S. mansoni and the viability of hemocytes and parasites was assessed. Next, IL-1β was added to sporocyst-hemolymph samples, the viability of sporocysts and hemocytes determined and then compared to control assays. The number of live sporocysts present after incubation for 1 h with hemolymph from M-line snails was significantly greater than the number seen when hemolymph from 13–16-R1 snails was tested. Nearly all sporocysts survived the 1 h incubation with M-line hemolymph, and most of the hemocytes attached to sporocysts were dead. In contrast, nearly all sporocysts were dead when hemolymph from 13–16-R1 snails was tested, and most attached hemocytes were alive. Addition of IL-1β to M-line hemolymph resulted in a dramatic increase in sporocyst death. Addition of IL-1β to 13–16-R1 hemolymph produced a small but significant increase in the rate of sporocyst death. These results indicate that the concentration of IL-1β present in hemolymph from B. glabrata is directly related to the ability of this snail to kill S. mansoni sporocysts in vitro.     

Fine Structure of the Oocyst Wall of Eimeria nieschulzi

SYNOPSIS. Oocysts of Eimeria nieschulzi from the laboratory rat, Rattus, norvegicus , were studied by scanning and transmission electron microscopy. Oocysts had a rough outer wall with apparent random depressions. The oocyst wall is composed of 2 layers: an osmiophilic outer layer consisting of a rough external and smooth internal surface, and a relatively thick, electron-lucent inner layer. The outer layer is composed of a dense, coarsely granular matrix. The inner layer consists of homogeneous fine granular material interspersed with coarse osmiophilic granules and contains one closely applied membrane on the outermost surface. Several raised lenticular areas are seen on the coarse outer surface of the inner layer. These layers are 102 (75–128) and 176 (135–204) nm thick, respectively.
The sporocyst wall is thin, consisting of 3 to 4 unit membranes, and measures 27 (18–34) nm thick.     

Wenyonella baghdadensis sp. n. from the Bandicoot Rat Nesokia indica in the Baghdad Area

SYNOPSIS. Oocysts of Wenyonella baghdadensis sp. n. were found in the feces of 2 of 12 bandicoot rats Nesokia indica Gray & Hardwicke from the Baghdad area. Sporulated oocysts were subspherical to broadly ellipsoidal, 25.4 (18–22) × 20.8 (15–28) μm, with a 2-layered wall, the outer wall being mammillated, without micropyle, micropylar cap, residuum, or polar granule. Sporozoites were ovoid, 11.8 (9–15) × 8.4 (6–10) μm, with Stieda body and residuum. Two sporozoites in each sporocyst were elongate, with granular cytoplasm and a refractile globule, the other 2 were bean-shaped, without granules or refractile globule. Sporulation time equalled 3 days at 22–24 C. Entamoeba coli and Giardia sp. cysts were also found in 3 rats each.     

Sarcocystis neurona (Protozoa: Apicomplexa): description of oocysts, sporocysts, sporozoites, excystation, and early development

Equine protozoal myeloencephalitis is a major cause of neurological disease in horses from the Americas. Horses are considered accidental intermediate hosts. The structure of sporocysts of the causative agent, Sarcocystis neurona, has never been described. Sporocysts of S. neurona were obtained from the intestines of a laboratory-raised opossum fed skeletal muscles from a raccoon that had been fed sporocysts. Sporocysts were 11.3 by 8.2 microm and contained 4 sporozoites. The appearance of the sporocyst residuum was variable. The residuum of some sporocysts was composed of many dispersed granules, whereas some had granules mixed with larger globules. Excystation was by collapse of the sporocyst along plates. The sporocysts wall was composed of 3 layers: a thin electron-dense outer layer, a thin electron-lucent middle layer, and a thick electron-dense inner layer. The sporocyst wall was thickened at the junctions of the plates. Sporozoites were weakly motile and contained a centrally or posteriorly located nucleus. No retractile or crystalloid body was present, but lipidlike globules about 1 microm in diameter were usually present in the conoidal end of sporozoites. Sporozoites contained 2-4 electron-dense rhoptries and other organelles typical of coccidian zoites. Sporozoites entered host cells in culture and underwent schizogony within 3 days.     

Eimeria crotalviridis sp. n. from Prairie Rattlesnakes, Crotalus viridis viridis, in New Mexico with Data on Excystation of Sporozoites and Ultrastructure of the Oocyst Wall

SYNOPSIS Oocysts of Eimeria crotalviridis sp. n. are described from prairie rattlesnakes, Crotalus viridis viridis in New Mexico on the basis of light and electron microscopy and in vitro excystation of sporozoites. Sporulated oocysts of E. crotalviridis are elliptical, 26.4 × 22.3 (23–29 × 20–24) μm with ovoid sporocysts 11.7 × 8.1 (11–13 × 7–9) μm. A micropyle, micropyle cap and polar bodies are absent, but oocyst and sporocyst residua and Stieda and substieda bodies are present. Excysted sporozoites are 12.4 × 2.8 (11–13 × 2–3) μm and have 1 large posterior refractile body and a nucleus with a prominent nucleolus. Ultrastructurally, the oocyst wall has 2 layers, a thick, electron-dense, highly sculptured outer layer composed of a fine granular matrix and a thin, granular, osmiophilic inner layer, separated from the outer layer by at least one unit membrane. These layers are 441 (353–510) and 21.6 (19–29) nm thick, respectively. Within 15 min after exposure to a trypsin-sodium taurocholate fluid, sporozoites of E. crotalviridis excysted from 5-month-old sporocysts.