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1.
Entomophthora brevinucleata, a fungal pathogen of gall midges, is described. The species occurs on at least 3 host species, including the wheat blossom midgeSitodiplosis mosellana Géhin andMycodiplosis sp.E. brevinucleata produces rhizoids, either monohyphal or comprising bundles of a few hyphae, without holdfasts. The hyphal bodies are subspherical with mean dimensions of 27.5×22.1 μm. The primary conidia are campanulate with mean dimensions from individual hosts of 11.2–18.9×8.7–15.8 μm. They contain 3–13 nuclei with a mean diameter of between 2.7 and 3.7 μm stained with lactophenol-aceto-orcein. The secondary conidia are of similar shape but smaller. Cystidia and resting spores were not observed.  相似文献   

2.
Perithecia of Erysiphe cichoracearum (powdery mildew) were found on several, but not all, accessions of Lactuca serriola, L. saligna, L. aculeata and L. serriola × L. sativa hybrid. Their occurrence varied between Lactuca species and different accessions of the same species. Perithecia were globular, had a mean diameter of 125.5 μm and contained an average 13–14 asci. Asci had mean dimensions of 55.0 × 26.1 μm and each contained two ascospores which measured an average 17.4 × 10.6 μm. There were however significant differences in the dimensions of spores and other structures obtained from different Lactuca accessions.  相似文献   

3.
4.
Fecal samples of 36 ground squirrels, Spermophilus beldingi, from Tioga Pass (elev. ca. 3315 m) in the Sierra Nevada, California, yielded oocysts of Eimeria beckeri in nine squirrels, E. citelli in four squirrels, E. beldingii n. sp. in two squirrels, and degenerated, unidentifiable oocysts in ten squirrels. Eimeria beldingii n. sp. oocysts are ellipsoidal, 30–34 × 24–30 (mean 32 × 26) μm with a two-layered, rough, striated wall, without a micropyle or residuum, with polar granules; they contain ellipsoidal or ovoid sporocysts 11–15 × 9–12 (mean 13 × 10) μm with a Stieda body and residuum.  相似文献   

5.
Two of 15 road-killed opossums examined for coccidia were found to be infected with a hitherto undescribed species of Eimeria, herein named Eimeria indianensis . The oocysts were spherical (63%) or slightly subspherical (37%) with a double-layered wall. The outer layer was ~1.5 μm thick, yellowish, striated, and appeared rough and pitted on the surface. A micropyle was absent. The spherical oocysts were 16.3 (13–18) μm in diameter; the subspherical ones, 17.6 (15–18) × 16.4 (14–17) μm. The sporocysts measured 9.1 (8–10) × 6.2 (6–7) μm and contained a granular residuum. The sporozoites were elongate, measuring 13.4 (13–15) × 1.8 (1.6-2.0) μm; no refractile globules were seen. The prepatent period was 10 days and the patent period ranged from 9–15 days. A few oocysts of an Isospora sp. were present in one opossum. It was not possible to confirm whether they were specifically of the opossum or of spurious origin.  相似文献   

6.
SYNOPSIS. Oocysts and endogenous stages of new species of Eimeria and Isospora from the house lizard, Gehyra mutilata, are described. The ellipsoid to subspherical 2-layered oocysts of E. cicaki averaged 24.0 × 21.0 μm. Polar granules are present. Micropyle and oocyst residuum are absent. Ellipsoid sporocysts average 12.2 × 9.0 μm. A sporocyst residuum is present, but the Stieda body is absent. Endogenous stages are in epithelial cells of the small intestine. The subspherical single-layered oocysts of I. thavari average 23.8 × 22.8 μm. The polar granule is present; micropyle and oocyst residuum are absent. Ellipsoid sporocysts average 12.8 × 9.4 μm. Stieda body and sporocyst residuum are present. There are endogenous stages in epithelial cells of the small intestine.  相似文献   

7.
SYNOPSIS. Eimeria tenggilingi is described from the pangolin or scaly anteater, Manis javanica, in Malaysia. The spheroid to subspheroid oocysts average 18.9 × 17.8 μm. The oocyst wall is composed of 3 layers, each ~ 0.6 μm thick. The 2 outer layers are striated and yellowish green. The inner layer is dark brown. One or 2 polar granules are present, but an oocyst residuum is absent. Ellipsoid sporocysts average 12.4 × 6.2 μm. A sporocyst residuum is present. This is the first Eimeria species reported from a host in the order Pholidota.  相似文献   

8.
SYNOPSIS. Toxoplasma ranae sp. n. is described from the brain of a leopard frog, Rana pipiens, probably from Mexico. Its pseudocysts were 72(55-106) × 48(29-70) μm in fixed sections. They contained an average of ~ 4,000 slightly curved elongate zoites measuring 4–5 × 0.5 μm, with a central, spherical, vesicular nucleus.  相似文献   

9.
ABSTRACT Thirteen eastern moles, Scalopus aquaticus, collected in West Texas were examined for coccidian oocysts; 11 (85%) were infected and eight (73%) of these had multiple infections representing two or more species. One cyclosporan, three eimerians, and two isosporans were studied and all are described as new species. Sporulated oocysts of Cyclospora megacephali n. sp. were subspheroidal, 18.5 × 15.7 (14–21 × 12–18) μm; they had sporocysts pointed at one end with Stieda bodies nearly as wide as the sporocysts themselves, and were 15.0 × 7.2 (11–17 × 6–9) μm; C. megacephali was found in four (31%) hosts. Sporulated oocysts of Eimeria scalopi n. sp. were spheroidal to subspheroidal, 13.6 × 12.6 (11–17 × 11–15) μm with sporocysts lemon-shaped, 8.7 × 5.5 (7–10 × 4–7) μm; it was found in six (46%) hosts. Sporulated oocysts of Eimeria aquatici n. sp. were asymmetrically ellipsoidal, 17.0 × 10.6 (14–20 × 9–14) μm, with sporocysts elongately ovoidal, 9.0 × 5.2 (8–11 × 4–6) μm; it was found in two (15%) hosts. Sporulated oocysts of Eimeria motleiensis n. sp. were subspheroidal, 17.0 × 15.3 (15–20 × 13–18) μm with sporocysts ovoidal, 10.7 × 6.8 (10–13 × 6–8) μm; it was found in seven (54%) hosts. Sporulated oocysts of Isospora motleiensis n. sp. were spheroidal to subspheroidal, 13.6 × 12.0 (10–17 × 8–15) μm with sporocysts broadly ovoidal, 9.5 × 6.7 (7–11 × 4–8) μm; it was found in nine (69%) hosts. Sporulated oocysts of Isospora aquatici n. sp. were subspheroidal, 20.9 × 18.4 (15–24 × 13–21) μm with sporocysts ellipsoidal, 11.8 × 9.0 (9–14 × 7–11) μm; it was found in two (15%) hosts.  相似文献   

10.
SYNOPSIS Oocysts of Eimeria dericksoni Roudabush, Eimeria mascoutini Wacha & Christiansen, and Eimeria vesicostieda sp. n. were isolated from the Spiny Soft-shell Turtle, Trionyx spiniferus LeSueur, in Iowa. The sporulated oocysts of E. dericksoni are redescribed to include, for the first time, the dimensions of the sporocysts (6.0–8.5 × 3.0–5.0 μm) and the structural appearance of the Stieda body (thinly convex); the oocysts of E. vesicostieda are newly described as being thickwalled, narrowly ovoid to narrowly ellipsoid, measuring 22.0–25.5 × 16.5–20.5 μm. and having a polar granule, a sporocyst residuum, and a vesicle-like Stieda body; the oocysts of E. mascoutini are documented photographically.  相似文献   

11.
ABSTRACT. Moles from England were examined for coccidian oocysts and all 64 Talpa europaea were infected; of 64 infected hosts, 56 (88%) had multiple infections representing two to six coccidian species when examined. Oocysts in 31 of the 64 samples remained unsporulated. Three eimerians and one isosporan were studied from the 33 fecal samples that had sporulated oocysts and these are described as new species; Cyclospora talpae Pellérdy & Tanyi, 1968, and Isospora sofiae (Golemansky, 1978) Levine & Ivens, 1979, are redescribed; and Cyclospora sp., similar to C. talpae, is discussed. Sporulated oocysts of C. talpae are ellipsoidal, 14.3 × 9.6 (12–19 × 6–13) μm with sporocysts ovoid, 9.4 × 5.7 (6–13 × 4–8) μm; it was found in 21 of the 33 (63.6%) sporulated samples. Sporulated oocysts of Cyclospora sp. are subspheroidal to ellipsoidal, 12.5 × 8.9 (10–14 × 6–12) μm with sporocysts ovoid, 8.6 × 5.3 (6–10 × 4–6) μm; it was found in 21 of the 33 (63.6%) sporulated samples. Sporulated oocysts of Eimeria avonensis n. sp. are elongate-ellipsoidal, 15.0 × 9.6 (13–20 × 7–12) μm with sporocysts ovoid, 6.6 × 3.6 (5–9 × 3–7) μm; it was found in 15 of the 33 (45.5%) sporulated samples. Sporulated oocysts of Eimeria berea n. sp. are subspheroidal, 12.1 × 10.5 (10–15 × 8–14) μm with sporocysts ovoid, 6.3 × 3.9 (5–10 × 2–5) μm; it was found in 8 of the 33 (24.2%) sporulated samples. Sporulated oocysts of Eimeria globula n. sp. are spheroidal, 20.9 × 19.9 (19–24 × 17–21) μm with sporocysts elongate-ovoid, 11.5 × 6.9 (9–16 × 6–9) μm; it was found in 3 of the 33 (9.1%) sporulated samples. Sporulated oocysts of Isospora sporopointaea n. sp. are subellipsoidal to ellipsoidal, 17.1 × 11.4 (13–21 × 8–14) μm with sporocysts ellipsoidal with both ends pointed, 11.9 × 5.9 (9–16 × 4–8) μm; it was found in 27 of the 33 (81.8%) sporulated samples. Sporulated oocysts of I. sofiae are spheroidal to subspheroidal, 12.2 × 11.0 (9–16 × 8–15) μm with sporocysts ovoid, 9.1 × 5.2 (6–13 × 3–8) μm; it was found in 25 of the 33 (75.8%) sporulated samples. To date, the coccidian parasites of talpids include two cyclosporans, 12 eimerians, and six isosporans, exclusive of the four new species described here.  相似文献   

12.
SYNOPSIS. Oocysts of Eimeria natricis sp. n. and Eimeria sipedon sp. n. were isolated from 2 Northern Water Snakes, Natrix sipedon sipedon (Linnaeus), in Iowa. Oocysts of E. natricis were elongate, slightly ovoid, averaging in size 32.3 × 17.5 μm; sporocysts averaged 15.7 × 8.2 μm. Oocysts of E. sipedon were broadly ovoid averaging in size 18.0 × 15.9 μm; sporocysts averaged 12.0 × 7.4 μm. In both species, sporocyst residua were present, but micropyles, polar granules and oocyst residua were lacking.  相似文献   

13.
ABSTRACT. 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 × 17.9(18-25 × 16-21) μm. Sporocysts were amorphous, gelatinoid envelopes 20.3 × 7.5 (17–24 × 7–9) μm. 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 × 24.4 (25–30 × 21–28) μm; a highly ornate outer oocyst wall gave the appearance of a ciliated ball. Sporocysts ovoid, pointed at both ends, were 17.0 × 9.0 (15–19 × 7–11) μm; this species was found in 4 of 45 (8.9%) U. talpoides. Sporulated oocysts of Eimeria talpoidei n. sp. were asymmetrical ovoid, 20.6 × 13.3 (18–23 × 12–15) μm, with sporocysts lacrimiform, 12.0 × 5.8 (10–14 × 5–7) μm. This species was found in 7 of 45 (15.6%) U. talpoides. Sporulated oocysts of Eimeria honshuensis n. sp. were ellipsoid, 15.5 × 11.4 (13–18 × 10–13) μm, with sporocysts ovoid, 9.1 × 5.2 (8–10 × 4–6) μm. 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 × 12.6 (13–17 × 11–13) μm, with sporocysts ellipsoid, 10.9 × 6.9 (10–13 × 6–8). This species was found in six of six D. pilirostris. Sporulated oocysts of Isospora urotrichi n. sp. were spheroid/subspheroid, 13.4 × 12.4 (11–16 × 9–14) μm, with sporocysts ovoid, 9.2 × 6.3 (8–11 × 5–7) μm. 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.  相似文献   

14.
Feces from a specimen of Tamandua tetradactyla (Linn.) from Portel, Para State, north Brazil, contained two different coccidial oocysts; one identified as Eimeria tamanduae Lainson 1968, and the other as a new species, described here as Eimeria corticulata n. sp. Oocysts of E. corticulata are ellipsoidal, 37.4 × 30.4 (31.2–43.7 × 23.7–35.0) μm, shape index (length/width) 1.2 (1.0–1.5). Oocyst wall 2.5–3.7 μm thick and composed of two layers; an outer thick, brown-yellow one with radial striations, and a thin inner smooth one: no visible micropyle. Oocyst residuum a large globule of about 10.7 × 10.3 μm, usually accompanied by a number of smaller attached globules. Sporocysts ellipsoidal, 21.0 × 11.0 (20.0–22.5 × 10.0–12.5) μm, with a conspicuous Stieda body: shape index 1.9 (1.6–2.2). Sporocyst residuum a small number of scattered granules: sporozoites 18.7 × 5.0 μm, with a large posterior refractile body. Eimeria zygodontomyis n. sp. is described in feces from Zygodontomys lasiurus (Lund) from the Serra dos Carajas, Para. Oocysts ellipsoidal to cylindrical, 16.5 × 12.0 (13.7–18.7 × 11.2–12.3) μm, shape index 1.4 (1.2–1.5). Wall colorless, smooth, single-layered and about 0.6 μm thick: no micropyle. No oocyst residuum, but a polar granule of about 1.8 × 1.0 μm is sometimes present. Sporocysts ellipsoidal, 8.4 × 5.5(7.5–8.7 × 5.0–6.2) μm, shape index 1.5 (1.4–1.7), with a thin colorless wall and a delicate Stieda body. Sporozoites enclose a compact residuum of about 2.5 × 3.7 μm.  相似文献   

15.
16.
During the summer season of 2003 and 2004, wilt syndromes of grapevine leaves (Cv. crimson) and vascular discolouration of roots have been observed in 2-year-old grapevine plants in the field at two sides in Gharbeia Governorate, Egypt. First, symptoms of wilt began on bottom leaves borderline as chlorosis and then these turned to necrotic spots and the leaves died. Wilt symptoms were spread to apical associated with vascular discolouration of roots and stem basal. Routine isolations of discoloured root tissue from diseased plant yielded eight isolates of Fusarium oxysporum Schlechtend only where no other fungi were developed. Microscopic examination revealed the presence of three shapes of microconidia, first is avoid shape non-septate measuring 2.5–3.0 μm × 6–10 μm, second is cylindrical with one septa measuring 2.6 μm × 17.0 μm and third shape also cylindrical with two septate measuring 3.0 μm × 20.0 μm. Macroconidia was rarely with three septate measuring 3.5– 4.0 μm × 35.0–38.0 μm, and chlamydospores were found singly or in pairs or chains. F. oxysporum isolates attacked grapevine plants (Cv. crimson) causing vascular wilt (66.7%) and root-rot syndrome (33.3%). In vitro isolates of F. oxysporum causing wilt of grapevine (Cv. crimson) varied for producing lytic enzymes, i.e. polygalacturonase (PG) and cellulase. The reactions of several grapevines (Cvs.) with a virulent isolate of F. oxysporum indicated the presence of two different symptoms, i.e. vascular wilt only on grapevine plants (Cv. crimson) and root-rot on the other grapevine (Cvs.), i.e. superior, Thompson, King robi and flame seedless. All F. oxysporum isolates caused vascular wilt of grapevine Cv. crimson, successfully reisolated from symptomatic vascular infected tissue and complete identification on the basis of colony, conidia morphology and host range at formae speciales level as F. oxysporum f. sp. herbemontis (Tochetto) Gordan. This is the first report of Fusarium wilt on grapevine in Egypt.  相似文献   

17.
Pleistophora oncoperae sp.n. is described from adults and larvae of Oncopera alboguttata and O. rufobrunnea. The main site of infection was muscle, though fat body and connective tissue were also infected. Fresh pansporoblasts measured about 25 μm in diameter and contained 16 to 32 or more spores with a mean size of 5.9 × 3.1 μm. Macrospores measuring 7.7 × 4.4 μm were also seen. The mean polar filament length was 158 μm; ultrastructural studies showed that the filament is normally arranged in 14 coils (range, 13 to 20) at an angle of 53.5° to the axis of the spore. The species was found to be distinct from all previously described Pleistophora reported from Lepidoptera.  相似文献   

18.
SYNOPSIS. Sphaeromyxa maiyai sp. n. (Myxosporidea: Myxiidae) is described from the gall bladder of the Pacific tomcod Microgadus proximus Girard, from Newport, Oregon. The plasmodial stage is discoid averaging between 1 and 2 cm. The spore averages 27.6 × 5.6 μm in breadth, with pyriform polar capsules measuring 9.3 × 3.7 μm. Scanning electron microscopy reveals the presence of numerous longitudinal striations.  相似文献   

19.
Abstract

A trypanosomatid flagellate, Herpetomonas sp., is recorded from an adult Mythimna separata (Walker) (Lepidoptera: Noctuidae). Promastigote, paramastigote, and opisthomastigote stages measured 3.4–12 × 1.3–4.3 μm, Giemsastained, with flagella measuring 13.8–18.7 μm. A few amastigotes (3.9–8.3 × 3.7–6.7 μm) were also observed. Fourteen larvae fed with a suspension of flagellates were found later to be infected with the protozoan. No flagellate infections were found in the hymenopteran parasitoid, Apanteles ruficus (Haliday), or the hyperparasitoid, Trichomalopsis sp.  相似文献   

20.
ABSTRACT. The life cycle and morphology of a previously undescribed species of Cryptosporidium isolated from commercial broiler chickens is described. The prepatent period for Cryptosporidium baileyi n. sp. was three days post oral inoculation (PI) of oocysts, and the patent period was days 4–24 PI for chickens inoculated at two days of age and days 4–14 for chickens inoculated at one and six months of age. During the first three days PI, most developmental stages of C. baileyi were found in the microvillous region of enterocytes of the ileum and large intestine. By day 4 PI, most parasites occurred in enterocytes of the cloaca and bursa of Fabricius (BF). Mature Type I meronts with eight merozoites first appeared 12 h PI and measured 5.0 × 4.9 μm. Mature Type II meronts with four merozoites and a large granular residuum first appeared 48 h PI and measured 5.1 × 5.1 μm. Type I meronts with eight short merozoites and a large homogeneous residuum first appeared 72 h PI and measured 5.2 × 5.1 μm. Microgamonts (4.0 × 4.0 μm) produced 16 micro-gametes that penetrated into macrogametes (4.7 × 4.7 μm). Macrogametes gave rise to two types of oocysts that sporulated within the host cells. Most were thick-walled oocysts (6.3 × 5.2 μm), the resistant forms that passed unaltered in the feces. Some were thin-walled oocysts whose wall (membrane) readily ruptured upon release from the host cell. Sporozoites from thin-walled oocysts were observed penetrating enterocytes in mucosal smears. The presence of thin-walled, autoinfective oocysts and the recycling of Type I meronts may explain why chickens develop heavy intestinal infections lasting up to 21 days. Oocysts of C. baileyi were inoculated orally into several animals to determine its host specificity. Cryptosporidium baileyi did not produce infections in suckling mice and goats or in two-dayold or two-week-old quail. One of six 10-day-old turkeys had small numbers of asexual stages only in the BF. Four of six one-day-old turkeys developed mild infections only in the BF, and sexual stages of the parasite were observed in only one of the four. All seven one-day-old ducks and seven two-day-old geese developed heavy infections only in the BF with all known developmental stages present.  相似文献   

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