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1.
Ahmed S.  Thandar 《Journal of Zoology》1994,234(2):341-351
Fourteen specimens of a shallow-water, sand-inhabiting, polytentaculate holothuroid, dredged from Durban, South Africa, are new and described as Phyllophorus (Phyllophorella) rosetta sp. nov. The new species is distinct in possessing an abundance of rosettes in all parts of the body wall, often in combination with tables typical of those of the Phyllophorus subgenus Phyllophorella Heding & Panning, 1954. In the form of its tables and rosettes the new species appears to be closely related to P. (P) contractura Cherbonnier, 1988 from Madagascar but differs from it in the form of its calcareous ring, the number of polian vesicles and the presence of rosettes throughout the body wall, instead of their restriction to the anal region. The presence of rosettes makes the new species, together with P. (P) contractura , a good intermediate between Phyllophorus and Lipotrapeza. The new species increases to nine the number of species now classified in the subgenus Phyllophorella. All nine species are keyed.  相似文献   

2.
Shichun  Sun  Jingrang  Lu 《Hydrobiologia》1998,367(1-3):175-187
A new genus and species of heteronemertean, Yinia pratensis gen. nov. and sp. nov., collected from low salinity waters (salinity 0.2–0.4 ‰) at Changjiang River Estuary, is described and illustrated. The species possesses a proboscis with an outer circular and an inner longitudinal muscle layer, and is placed in family Lineidae sensu Gibson. The following combination of morphological features distinguishes the new species from any other genera in this family: proboscis with two muscle crosses; dermis without connective tissue layer between gland cells and body wall outer longitudinal muscle layer; rhynchocoel wall circular muscles not interweaving with adjacent body wall longitudinal muscles; foregut with circular somatic muscles and subepithelial gland cell layer; neurochord cells present in central nervous system; caudal cirrus missing; blood system developed into alimentary plexus extending almost the full length of the body. Another significant character is that the lobular excretory cells are extremely well developed which may represent adaptation to water of low salinity. This revised version was published online in July 2006 with corrections to the Cover Date.  相似文献   

3.
Kajihara  Hiroshi  Gibson  Ray  Mawatari  Shunsuke F. 《Hydrobiologia》2001,456(1-3):187-198
A new genus and species of monostiliferous hoplonemertean, Diopsonemertes acanthocephala gen. et sp. nov., is described from Otsuchi Bay, Japan. Significant anatomical features of the new form include a body wall longitudinal musculature anteriorly divided into inner and outer layers by connective tissue, no pre-cerebral septum, the presence of a thin coat of diagonal muscle fibres between the body wall longitudinal and circular muscle layers in the foregut body region, cephalic retractor muscles derived only from the inner portion of the divided longitudinal muscles and a rhynchocoel more than half the body length.  相似文献   

4.
Two new species of Tubificoides are described from the west coast of Florida. Both species have large lateral openings of the penis sheaths with proximal flap-like projections. Tubificoides pollex sp.n. is characterized by (1) papillate body wall in postclitellar segments; (2) possession of hair and bifid setae anteriorly, and only bifid setae in pcstclitellar segments; and (3) conical penis sheaths with a lateral opening and a flap-like projection on the proximal margin. The setal distribution of the new species is similar to that of T. bakeri Brinkhurst, 1986, which is redescribed on the basis of new material. Tubificoides lunatus sp.n. is similar to T. pollex except that the flap-like projections of the penis sheaths are crescent shaped, all the somatic setae are bifid, and body wall papillae are absent. Records of Tubificoides brownae Brinkhurst & Baker, 1979, and T. imajimai Brinkhurst, 1986, from the Gulf of Mexico and Caribbean, respectively, are also presented. The latter species was previously known only from subtropical regions of Japan and the People's Republic of China.  相似文献   

5.
Two new species of the Lagenidiales endoparasitic on the nematode Rhabditis are reported from Ontario soils. In Myzocytium lenticulare the biflagellate zoospores encyst at any point on the cuticle of the host and penetrate directly through the wall. Sexual reproduction in this species is by oogamy. The antheridial protoplast migrates through a pore in the adjacent wall and fuses with the oogonial protoplast to produce a thick-walled reticulate oospore. In Lagenidium caudatum large biflagellate zoospores encyst at or near the body orifices of the host. Many of the zoospores possess a distinct tail-like appendage. Germination tubes from the encysted zoospores penetrate the body orifices to infect the host. The thallus in this species is distinctive in being composed of narrow, irregular hyphae which fill the host. No sexual stage is known.  相似文献   

6.
Twenty species of bats (Molossidae, Vespertilionidae) were collected from California, New Mexico, Oregon, South Carolina, Utah, and Baja California Norte (Mexico), and 29 of 404 (7%) animals, including Antrozous pallidus, Eptesicus fuscus, Myotis auriculus, Myotis californicus, Myotis ciliolabrum, Myotis evotis, Myotis lucifugus, Myotis thysanodes, Myotis vivesi, Myotis volans, Myotis yumanensis, and Nycticeius humeralis were infected with Eimeria spp., which represent 6 new species. Sporulated oocysts of a new species from A. pallidus are subspheroidal, 24.8 x 21.6 (22-27 x 19-24) microm with a polar granule and a large globular residuum. The oocyst wall is sculptured, with 2 layers, approximately 1.5 thick. Ovoidal sporocysts are 11.5 x 7.8 (9-13 x 7-10) microm, with Stieda body and residuum of many large granules. Sporulated oocysts of a new species from M. californicus are subspheroidal, 20.7 x 18.2 (19-23 x 16-20) microm, with 1-7 tiny polar granules, but without oocyst residuum. The oocyst wall is rough, with 2 layers, approximately 1.4 thick. Ovoidal sporocysts are 11.2 x 7.3 (10-12 x 7-8) microm, with Stieda body and a globular residuum. Sporulated oocysts of a second new species from M. californicus are subspheroidal, 23.1 x 20.7 (20-26 x 19-23) microm, with residuum and 1 polar granule, but a micropyle is absent. The oocyst wall is rough with 2 layers, approximately 1.5 thick. Ovoidal sporocysts are 12.5 x 7.2 (11-14 x 7-8) microm, with a Stieda body and residuum. Sporulated oocysts of a new species from M. ciliolabrum are subspheroidal, 24.9 x 20.1 (18-27 x 17-23) microm, with 1-2 polar granules, but without micropyle and residuum. The oocyst wall is rough with 2 layers, approximately 1.5 thick. Ellipsoidal sporocysts are 12.5 x 9.0 (8-14 x 7-10) microm, with Stieda and substieda bodies and residuum. Sporulated oocysts of a new species from M. evotis are subspheroidal, 21.3 x 18.6 (20-24 x 15-20) microm, with a prominent polar granule, but without micropyle and residuum. The oocyst wall is smooth with 2 layers, approximately 1.0 thick. Ovoidal sporocysts are 12.2 x 8.0 (11-13 x 7.5-9) microm, with Stieda and substieda bodies and residuum. Sporulated oocysts of the new species from N. humeralis are subspheroidal, 22.4 x 18 (21-24 x 17-20) microm, with 1-3 polar granules, but residuum and micropyle are absent. The oocyst wall is lightly sculptured with 2 layers, approximately 1.4 thick. Ovoidal sporocysts are 10.9 x 7.7 (9-12 x 6-8) microm, with Stieda body and residuum. Sporulated oocysts of E. pilarensis Scott and Duszynski, 1997 and those of at least 12 other morphological forms were seen in the other infected bats; these latter forms were seen in too few numbers to be adequately described as new species.  相似文献   

7.
Ahmed S.  Thandar 《Journal of Zoology》1986,210(4):483-488
A new genus and species of a dendrochirotid holothurian, Pawsonellus africanus , from shallow waters off the east coast of Southern Africa, are described. The new genus is compared with several genera within the family Cucumariidae and it is concluded that it is not closely related to any of them. Although its body wall spicules strongly resemble those of Panningia hyndmani (Thompson), notably the typical form described by Madsen (1942), there are several features which suggest that the two species are not congeneric.  相似文献   

8.
Two new species of Eimeria were observed in the feces of captive white-tailed deer fawns, Odocoileus virginianus, from Alabama. The first new species was easily recognized because of its small size. Sporulated oocysts are spherical, average 10.2 by 10.0 microm, and lack a micropyle and oocyst residuum. Oocysts contain a polar granule and elongate-ellipsoidal sporocysts that measure 6.7 by 3.1 microm. A Stieda body is present on the sporocysts. Oocysts were observed in the feces, and gamonts and oocysts were observed in the jejunum of a month-old fawn from Minnesota that died from enteritis due to this species. Oocysts of this small species were present in 5 of the 6 white-tailed deer fawns examined. Oocysts of a second new species are ellipsoidal and average 29.5 by 24.6 microm. The oocyst encloses an oocyst residuum, polar granule, and elongate-ellipsoidal sporocysts that average 16.0 by 9.0 microm. A Stieda body and substieda body are present on the sporocysts. Oocysts of the second new species were present in 4 of the 6 white-tailed deer fawns examined. Oocysts of E. ivensae are ovoid or flask-like and average 32.0 by 20.8 microm. The oocyst wall is rough, contains a micropyle, and encloses elongate-ellipsoidal sporocysts that average 16.5 by 7.8 microm. A Stieda body is present on the sporocysts. Oocysts of E. ivensae were present in 4 of the 6 white-tailed deer fawns. Oocysts of E. odocoilei are spherical or slightly subspherical and measure 24.7 by 21.5 microm. They enclose ovoid sporocysts that average 12.7 by 8.8 microm. A Stieda and substieda body are present on the sporocyst. Oocysts of E. odocoilei were present in 4 of the 6 white-tailed deer fawns.  相似文献   

9.
Examination of faecal samples from semi-captive western Derby elands Taurotragus derbianus derbianus Gray, in the Bandia and Fathala Reserves of Senegal, revealed the presence of o?cysts of the genus Eimeria Schneider, 1875 that we considered to represent a new species, Eimeria derbiani n. sp. The new species possesses nearly ellipsoidal o?cysts (length/width ratio 1.3) with a bi-layered wall and an average size of 27.6 × 21.5 μm. E. derbiani possesses a micropyle covered by a micropylar cap and ovoidal, single-layered sporocysts with an average size of 14.9 × 7.7 μm, each with a Stieda body. Sporozoites of E. derbiani possess a large refractile body and a nucleus. Sporulation lasted for 2 days at 23°C. The new species is differentiated from the two species parasitising Taurotragus oryx Pallas, E. canna Triffitt, 1924 and E. triffittae Yakimoff, 1934.  相似文献   

10.
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.  相似文献   

11.
Between 1985 and 1987, fecal samples were collected from 71 bats representing 14 species (Desmodontidae, Molossidae, Noctilionidae, Phyllostomidae, Vespertilionidae) from 8 localities in 3 states (Beni, Pando, Santa Cruz) in Bolivia, South America. Of these, 2 black myotid bats (Vespertilionidae), Myotis nigricans, and 1 tent-making bat (Phyllostomidae), Uroderma magnirostrum, had oocysts in their feces that represent undescribed species of Eimeria. The new species from M. nigricans (2/4, 50%) has sporulated oocysts that are subspheroidal, 18.9 x 16.9 (17-23 x 14-20) microm, without a micropyle; oocyst residuum of 6-8 spheroidal globules and 1 highly refractile polar granule are present. The oocyst wall has 2 layers (approximately 1.3 microm thick), with a rough outer layer. Ovoidal sporocysts are 10.1 x 7.4 (7-14 x 5-10) microm, with a Stieda body, substieda body, and a sporocyst residuum. The new eimerian species from U. magnirostrum (1/2, 50%) has sporulated oocysts that are subspheroidal to ellipsoidal, 23.8 x 20.8 (20-26 x 19-24) microm, without micropyle or oocyst residuum, but 1-3 polar granules are present. The oocyst wall has 2 layers (approximately 1.5 microm thick), with a rough, mammilated outer layer. Ovoidal sporocysts are 11.6 x 8.6 (10-12 x 7-10) microm, with a Stieda body, substieda body and a sporocyst residuum.  相似文献   

12.
A new species of parasitic nematode, Neoascarophis macrouri n. sp. (Cystidicolidae), is described from the stomach and stomach wall of the marine deep-water fish Macrourus berglax (onion-eye grenadier) in the eastern Greenland Sea (North Atlantic Ocean). The new species, studied using both light and scanning electron microscopy, is characterised mainly by the location of the vulva near the posterior end of the body (a short distance anterior to the anus), non-filamented eggs, the structure of the mouth, a short vestibule and the length of the spicules (567-615 and 144-156 mum). Metabronema insulanum Solov'eva, 1991 is transferred to Neoascarophis as N. insulana (Solov'eva, 1991) n. comb.  相似文献   

13.
Tissue displacement of various body surfaces and the auditory midbrain sensitivities to sound were measured in Atelopus species with or without a tympanic middle ear (“eared” and “earless”, respectively). Tissue displacement (vibration) of body regions was measured by laser Doppler vibrometer . The body wall directly overlying the lung is most dramatically displaced by sound pressure in all species tested. The otic (lateral head) region showed low displacement in earless species, but significant displacement to high-frequency sound in eared species. Peak tissue displacement of the body wall occurred within the frequency range of each species' advertisement vocalization. Peak tissue displacement of the otic region of the eared species also occurred within these frequencies. Multi-unit neurophysiological recordings of the auditory midbrain (torus semicircularis) also were obtained. Auditory sensitivity curves showed three distinct regions of sensitivity at low, middle, and high frequencies, the latter located within the frequency range of each species' advertisement vocalization. The correlation between auditory midbrain sensitivity and tissue displacement of the body wall region at advertisement vocalization frequencies, suggests that the body wall/lungs serve as the route of sound transfer to the inner ear in earless species and possibly in the eared species as well. Accepted: 4 April 1998  相似文献   

14.
A gill-associated Perkinsus sp. isolated from the softshell clam (Mya arenaria) is described as a new species, P. chesapeaki sp. nov. Examination of the parasite in seawater cultures revealed life cycle stages and zoosporulation processes similar to those described for other species of the genus Perkinsus. Prezoosporangia developed thickened cell walls upon contraction of the cytoplasm and development of a distinctive clear area between the cell wall and the protoplast. Successive bipartition of the protoplast led to the formation of hundred's of zoospores within mature sporangia. Zoospores were released into seawater through one or more discharge tubes. Ultrastructural studies revealed an oblong zoospore possessing two flagella that arose from a concave side located in the upper third of the zoospore body. The anterior flagellum possessed a unilateral array of hair-like structures. A large anterior vacuole and basolateral nucleus dominated the cytoplasm of the zoospore body. The presence of a rudimentary apical complex including an open-sided conoid, rhoptries, micronemes, and subpellicular microtubules were also discerned. Differences in zoospore morphology, and sequence analyses of two genes previously reported, support the designation of the gill-associated Perkinsus from the softshell clam as a new species.  相似文献   

15.
SUMMARY Molecular phylogenetics suggests that the Sipuncula fall into the Annelida, although they are morphologically very distinct and lack segmentation. To understand the evolutionary transformations from the annelid to the sipunculan body plan, it is important to reconstruct the ancestral states within the respective clades at all life history stages. Here we reconstruct the ancestral states for the head/introvert retractor muscles and the body wall musculature in the Sipuncula using Bayesian statistics. In addition, we describe the ontogenetic transformations of the two muscle systems in four sipunculan species with different developmental modes, using F-actin staining with fluorescent-labeled phalloidin in conjunction with confocal laser scanning microscopy. All four species, which have smooth body wall musculature and less than the full set of four introvert retractor muscles as adults, go through developmental stages with four retractor muscles that are eventually reduced to a lower number in the adult. The circular and sometimes the longitudinal body wall musculature are split into bands that later transform into a smooth sheath. Our ancestral state reconstructions suggest with nearly 100% probability that the ancestral sipunculan had four introvert retractor muscles, longitudinal body wall musculature in bands and circular body wall musculature arranged as a smooth sheath. Species with crawling larvae have more strongly developed body wall musculature than those with swimming larvae. To interpret our findings in the context of annelid evolution, a more solid phylogenetic framework is needed for the entire group and more data on ontogenetic transformations of annelid musculature are desirable.  相似文献   

16.
Summary The toxicity of 23 species of shallow-water antarctic echinoderms from McMurdo Sound was investigated using Gambusia affinis (Vertebrata: Pisces) as a test organism. Ichthyotoxicity assays were conducted on the body wall tissues of thirteen species of asteroids and three species of holothuroids, the tests of three species of echinoids and the arms of three species of ophiuroids and one species of crinoid. Patterns of toxicity were class-specific, with varying degrees of toxicity occurring exclusively among the Asteroidea and Holothuroidea. Seven of the thirteen species of asteroids were mildly to highly toxic (54%), while one of the three holothuroids was mildly and one highly toxic. Toxicity was not related to the level of calcification of the body wall and energy level in asteroids. The only armored asteroid, Notasterias armata, was non-toxic. The occurrence of toxins in the body tissues of antarctic echinoderms is similar in pattern and frequency with that of temperate and tropical species.  相似文献   

17.
18.
Parahupehsuchus longus is a new species of marine reptile from the Lower Triassic of Yuan’an County, Hubei Province, China. It is unique among vertebrates for having a body wall that is completely surrounded by a bony tube, about 50 cm long and 6.5 cm deep, comprising overlapping ribs and gastralia. This tube and bony ossicles on the back are best interpreted as anti-predatory features, suggesting that there was predation pressure upon marine tetrapods in the Early Triassic. There is at least one sauropterygian that is sufficiently large to feed on Parahupehsuchus in the Nanzhang-Yuan’an fauna, together with six more species of potential prey marine reptiles with various degrees of body protection. Modern predators of marine tetrapods belong to the highest trophic levels in the marine ecosystem but such predators did not always exist through geologic time. The indication of marine-tetrapod feeding in the Nanzhang-Yuan’an fauna suggests that such a trophic level emerged for the first time in the Early Triassic. The recovery from the end-Permian extinction probably proceeded faster than traditionally thought for marine predators. Parahupehsuchus has superficially turtle-like features, namely expanded ribs without intercostal space, very short transverse processes, and a dorsal outgrowth from the neural spine. However, these features are structurally different from their turtle counterparts. Phylogeny suggests that they are convergent with the condition in turtles, which has a fundamentally different body plan that involves the folding of the body wall. Expanded ribs without intercostal space evolved at least twice and probably even more among reptiles.  相似文献   

19.
A caryotropic species of coccidium, Isospora viridanae n. sp. (Apicomplexa: Eimeriidae). has been found as a parasite in the Canarian skink, Chalcides viridanus Gravenhorst, 1851, from Tenerife, Spain, and is described here as a new species. Fully sporulaled oocysts of Isospora viridanae are spherical and measure 21.6 (1 7.6–23.4) nm in diameter. Mtcropyle, oocyst residuum and polar granule are ali absent. Oocysts of this coccidian, with a smooth bilayered wall, contain 2 ovoid sporocysts 13.2 (11.7–14.0) by 9.5 8.2–10 5) μm. A sporocyst residuum is present as well as a Stieda body and a substieda body. Most oocysts are found to be at the beginning of sporulanon when excreted and show 2 spherical sporoblasts. Sporulation is completed within 24 to 48 h at 23 × 2°C Sporozoites are 13–14 μm long and are about 2.5–3 μ m wide. Endogenous stages of schizogony and gamogony develop in the nuclei of epithelial cells from the small intestine of the skink. Comparisons with other species of the genus found in lacertilian hosts indicate that it is a new species.  相似文献   

20.
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