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1.
An undescribed species of Haematoloechus inhabits the lungs of Rana vaillanti in northwestern Costa Rica. The new species is most similar morphologically to H. medioplexus, having a very small, but well-developed, ventral sucker and lacking extracecal uterine loops, and apparently was mis-identified previously as H. medioplexus in Rana palmipes from Colombia. It differs from H. medioplexus, notably by (1) the shape of the oral sucker, which is elliptical in H. meridionalis and spherical in H. medioplexus; (2) the posterior extent of the vitelline fields, which terminate at the same level in H. medioplexus, but always at different levels in H. meridionalis; (3) the position of the testes, which are immediately posterior to the seminal receptacle and are close together in the new species and far from the seminal receptacle and separated from each other in H. medioplexus; and (4) the location of the genital pore, which is ventral to the cecal bifurcation in the new species and ventral to the pharynx in H. medioplexus. In addition, the new species is unique among members of Haematoloechus by having flaps of tissue on the interior margins of the ventral sucker. The new species shows almost 5% sequence divergence from H. medioplexus in the variable D1 region of the 28s rDNA, complementing the morphological differences.  相似文献   

2.
Haematoloechus floedae was originally described from the lungs of Rana catesbeiana in Texas, and later reported in Florida, in the United States. It was proposed to be synonymous with H. breviplexus, H. parviplexus, and H. varioplexus. We obtained specimens of H. floedae from Rana brownorum and R. vaillanti in Yucatán, Mexico; R. cf. forreri and R. taylori in Guanacaste, Costa Rica; and R. catesbeiana in Georgia and California. Some specimens were processed for morphological study; sequences of the 28S of the rDNA and the mitochondrial COI were obtained from several specimens of each population. Phylogenetic analysis of molecular data indicates studied populations constitute a single taxon, different from H. varioplexus, H. breviplexus, and H. parviplexus. Some morphological characters remain constant among populations of H. floedae, and are useful for differentiating this species. These include the oral sucker-pharynx ratio, oral sucker-ventral sucker ratio, ovary and testes shape, extension of uterine longitudinal loops, and extension of vitelline follicles (in fully developed worms). Sequence homogeneity among populations of H. floedae suggests a recent spread, perhaps due to the introduction of R. catesbeiana for culture to the western United States, southeast Mexico, and Costa Rica.  相似文献   

3.
A new species of Urotrema inhabits Norops oxylophus and Norops cupreus from the Area de Conservación Guanacaste, Costa Rica. The new species is most similar to Urotrema scabridum but differs by having a relatively longer esophagus, at least 10% of the total body length versus 4-8% in U. scabridum; an oral sucker width: ventral sucker width ratio less than 1 : 1 (averaging 1 : 0.76) versus 1 : 1 or greater; an oral sucker width : pharyngeal width ratio less than 1 : 0.5 (averaging 1 : 0.42) versus greater than 1 :0.5; and by having many transversely oriented posttesticular uterine loops versus a few vertically oriented posttesticular uterine loops.  相似文献   

4.
Metacercariae survival patterns and their distribution in second intermediate odonate hosts were examined for 4 species of frog lung flukes. Surveys of aquatic larvae and recently emerged teneral dragonflies and damselflies indicated that prevalence and mean abundance of Haematoloechus spp. metacercariae were significantly lower in teneral dragonflies than larval dragonflies, while there was no significant difference in prevalence or mean abundance of Haematoloechus spp. metacercariae among larval and teneral damselflies. Experimental infections of dragonflies indicated that metacercariae of Haematoloechus coloradensis and Haematoloechus complexus were located in the head, thorax, and branchial basket of dragonflies, whereas metacercariae of Haematoloechus longiplexus and Haematoloechus parviplexus were restricted to the branchial basket of these hosts. Metacercariae of H. coloradensis, H. complexus, and H. longiplexus infected the head, thorax, and abdomen of damselflies, but these insects were resistant to infection with H. parviplexus. Subsequent metamorphosis experiments on experimentally infected dragonflies indicated that most metacercariae of H. longiplexus were lost from the branchial basket during metamorphosis, but most metacercariae of H. coloradensis, H. complexus, and H. parviplexus survived dragonfly metamorphosis. These observations suggest that the observed ecological host specificity of H. longiplexus in semiterrestrial leopard frogs may be due to few metacercariae of H. longiplexus reaching these frogs in a terrestrial environment. Because of the uncertain validity of Haematoloechus varioplexus as a distinct species from its synonym H. parviplexus, their morphological characters were reevaluated. The morphological data on H. varioplexus and H. parviplexus indicate that they differ in their acetabulum length and width, ovary shape, testes length, and egg length and width. Experimental infections of plains leopard frogs, northern leopard frogs, and bullfrogs with worms from bullfrogs indicate that the synonymy of H. parviplexus with H. varioplexus is not warranted, and that these flukes are distinct species, i.e., H. parviplexus in bullfrogs and H. varioplexus in plains leopard frogs and northern leopard frogs.  相似文献   

5.
A new species in the little-known digenean fauna of Paraguayan birds is described in detail, especially in relation to its terminal genitalia. The new form, Megalophallus deblocki n. sp., is a microphallid from the intestine of the snail kite Rostrhamus sociabilis (Vieillot). It is differentiated in detail from its congeners, but differs mainly in having a substantially larger phallus (e.g. in relation to the ventral sucker), a smaller ventral sucker and smaller eggs. Comments are included on the functional morphology of the terminal genitalia.  相似文献   

6.
Molecular evidence is interpreted in the light of morphology to examine the validity of several species of Haematoloechus described as Mexican endemics. Internal transcribed spacers 1 and 2 and 28S ribosomal genes were sequenced for 11 isolates. Phylogenetic analysis of separate partitions and combined databases was conducted. Results were analyzed, in the light of morphological evidence. Haematoloechus macrorchis is proposed as a junior synonym of Haematoloechus longiplexus. Haematoloechus pulcher is a sibling species with Haematoloechus complexus in Lerma wetlands. In Mexico, Haematoloechus medioplexus is distributed along the east coast coinciding with the distribution of Rana berlandieri. The sister species of H. medioplexus is Haematoloechus coloradensis, sharing the distribution of the uterus as a synapomorphic character. Haematoloechus illimis is more closely related to H. medioplexus and H. coloradensis than to H. complexus. It can be distinguished by the distribution of the uterus, lobed ovary, and testes.  相似文献   

7.
A new species in the little-known digenean fauna of Paraguayan birds is described in detail, especially in relation to its terminal genitalia. The new form, Megalophallus deblocki n. sp., is a microphallid from the intestine of the snail kite Rostrhamus sociabilis (Vieillot). It is differentiated in detail from its congeners, but differs mainly in having a substantially larger phallus (e.g. in relation to the ventral sucker), a smaller ventral sucker and smaller eggs. Comments are included on the functional morphology of the terminal genitalia.  相似文献   

8.
Species in the genus Notocotylus (Trematoda, Notocotylidae) are cosmopolitan parasites of mainly aquatic birds and, to a lesser extent, mammals. In this paper we describe Notocotylus primulus n. sp. parasitizing the Crested Duck, Lophonetta specularioides, from the Patagonian coast, southwestern Atlantic Ocean, based on morphological and molecular data. The new species could be distinguished from its congeners by the combination of several features; among them, the position of the genital pore that is prebifurcal and located close to the posterior margin of the oral sucker, a greater number of both ventral papillae and uterine loops, and a large cirrus sac. Molecular results of the ITS2 sequence support the location of this new species in the genus Notocotylus due to a close relationship with Notocotylus malhamensis (the lower genetic distance of the ITS2 sequences).  相似文献   

9.
A new hepatic dicrocoeliid species, Brachylecithum mackoi n. sp. (Digenea, Dicrocoeliidae), is described from the European hedgehog, Erinaceus europaeus (L.) (Insectivora, Erinaceidae). An infected host was found in the Mediterranean island of Elba (Italy), and more than 60 individuals were isolated from the biliary ducts. The holotype and 55 paratypes were examined. Brachylecithum mackoi n. sp. differs from congeneric species found in mammal hosts by having well-developed lappets in the ventral sucker, a sloping uterus between anterior testis and acetabulum, no overlap between vitellaria, and metrical features in the body size, sucker diameters, cirrus sac, and size of eggs. The only other Brachylecithum species of erinaceids in Europe and Africa, Brachylecithum aetechini Dollfus, 1951, differs from the new species in the above-mentioned morphological characters, greater dimensions of the body, and oral sucker, pharynx, cirrus sac, and egg dimensions. The presence of B. mackoi n. sp. in Elba Island is discussed in the light of apparent host specificity of erinaceid dicrocoeliids and geographical distribution of Palearctic and Ethiopian Erinaceidae.  相似文献   

10.
This report describes the first occurrence of Polystomoides brasiliensis n. sp. (Monogenea: Polystomatidae), a new monogenean species in the buccal and pharyngeal cavities of the freshwater turtles in Brazil. Live monogeneans were collected from Hydromedusa maximiliani and Phrynops geoffroanus at the Mariano Procópio Museum's lake, in Juiz de Fora, Minas Gerais, Brazil. Polystomoides brasiliensis differs from all other species of this genus in having 8-9 genital spines, except for Polystomoides uruguayensis, which has 8-10 genital spines. However, the new species differs morphometrically from P. uruguayensis in the greater size of the outer and inner hamuli, as well as having a testis that is proportionally greater than the pharynx and oral sucker. The current study is the first report of monogeneans in chelonians of Brazil, and the first record of helminths in H. maximiliani.  相似文献   

11.
Three species of neodiplostomula are known to inhabit the European grass snake, Rhabdophis tigrina, in the Republic of Korea: Pharyngostomum cordatum (large-sized neodiplostomula), an intestinal trematode of cats; Neodiplostomum seoulense (small-sized neodiplostomula), an intestinal trematode of humans and rodents; and Neodiplostomum leei (small-sized neodiplostomula), which migrates to the livers of rodents and is an intestinal trematode of birds. The present study describes a fourth species, Neodiplostomum (Conodiplostomum) boryongense n. sp. (Digenea: Neodiplostomidae), based on adult flukes recovered from the small intestines of chicks experimentally infected with small-sized neodiplostomula from the grass snake. The new species differs from 13 previously known species. It also differs from N. seoulense in its larger body size, severely bilobed testes, and smaller genital atrium, and from N. leei in its larger body size, smaller ventral sucker, presence of a genital cone, and vitelline follicles distributed chiefly in the forebody. The new species does not migrate to the livers of rodents nor does it develop to adulthood in the rodent intestines. However, the neodiplostomula of the new species are indistinguishable from those of the other 2 species. Results show that at least 4 species of neodiplostomula inhabit the grass snake in the Republic of Korea.  相似文献   

12.
Stephanostomum kovalevae Parukhin, 1968 from the intestine of Lophius vomerinus off Swakopmund, Namibia, is redescribed. It is characterised by its large number (c. 73-88) of circum-oral spines, its relatively very long hindbody and the vitellarium reaching close to or just overlapping the ventral sucker. S. beukelaardori n. sp., from the intestine of Zenopsis conchifera off Walvis Bay, Namibia, is described. It belongs to the group of species where the vitellarium reaches the ventral sucker, and which has c. 32-38 circum-oral spines. It is closest to S. casum (Linton, 1910), but differs in lacking the lining of prominent spines in the ejaculatory duct, probably in egg-size and in both forebody and hindbody lengths.  相似文献   

13.
Parvatrema chaii n. sp. (Digenea: Gymnophallidae) is described using the worms recovered from experimentally infected mice in Korea. The metacercariae were collected from surf-clams, Mactra veneriformis, from a tidal flat in Sochon-gun, Chungchongnam-do. The metacercariae were elliptical (0.262 x 0.132 mm), and the genital pore had an anterior arch of 16-17 sensory papillae in scanning electron microscopic view. Adult worms were ovoid to foliate (0.275-0.303 by 0.140-0.150 mm), and their characteristic features included the presence of lateral lips, short esophagus, genital pore located some distance anterior to the ventral sucker, club-shaped seminal vesicle, a compact to slightly lobed vitellarium, elliptical eggs (0.018-0.020 by 0.010-0.013 mm), and absence of the ventral pit. This gymnophallid is classified as a member of the genus Parvatrema because of the location of the wide genital pore some distance from the ventral sucker, and the absence of the ventral pit. It differs from previously reported Parvatrema species, including the type species, P. borinquenae. In particular, the morphologies of the vitellarium and the genital pore with an anterior arch of 16-17 sensory papillae are unique features. Therefore, we propose it as a new species, Parvatrema chaii n. sp. (Digenea: Gymnophallidae).  相似文献   

14.
Macroderoides minutus n. sp. is described based on specimens collected from the Florida gar (Lepisosteus platyrhincus) from Orange Lake, Alachua County, Florida. The new species is the ninth recognized species of Macroderoides and is morphologically closest to Macroderoides flavus and Macroderoides typicus. It differs from both species in having a smaller body, ventral sucker larger than the oral sucker, substantially lower body length to width ratio, fewer and larger eggs, and other characters. A comparison of sequences of nuclear rDNA (partial 18S, complete ITS region, and partial 28S) of the new species, with sequences of 5 other Macroderoides, convincingly supports the status of M. minutus as a new species. Molecular phylogenetic analysis, including all North American Macroderoides species except for Macroderoides parvus, has demonstrated the presence of 2 distinct clades, 1 including Macroderoides spinifer + (Macroderoides minutus n. sp. + Macroderoides texanus) and the other including Macroderoides trilobatus + (M. typicus + M. flavus). The tree topology suggests that the similarity in body proportions among M. minutus n. sp., M. typicus + M. flavus is not a result of close phylogenetic relationship. It has also revealed for the first time the phylogenetic affinities of M. flavus, which is the only North American member of Macroderoides that switched from holostean fishes to teleosts.  相似文献   

15.
16.
A new genus and species of nanophyetid,Baiohelmins elegans, is described from the intestine of the Australian water rat,Hydromys chrysogaster Geoffroy, 1804 in North Queensland. The new genus differs from previously described forms by the combination of the following characters: vitelline follicles restricted to a small group posterior to each testis, cirrus pouch present and caeca not extending posterior to the ventral sucker.  相似文献   

17.
Carex qingliangensis D. M. Weng, H. W. Zhang & S. F. Xu, a new species of the Cyperaceae from Zhejiang, China, is described with illustrations. The new species is morphologically similar to C. dolichostachya Hayata and C. tianmushanica C. Z. Zheng & X. F. Jin, but differs from the former in having perigynia sparsely pubescent and achenes constricted into a short neck at apex. It differs from the latter in having achenes not contracted in the middle part.  相似文献   

18.
Malawitrema staufferi n. gen., n. sp., an unusual digenean, is described from Clarias mossambicus (type host) and Bagrus meridionalis from Lake Malawi. It has a small, pyriform body, with a spinous tegument. The ceca are relative short, not reaching to the testes. The 2 testes are symmetrical in the middle hind body. The cirrus sac is long and narrow, reaching into hind body. The genital pore is median, immediately anterior to the ventral sucker. The ovary is pretesticular, and a canalicular seminal vesicle and Laurer's canal are present. The uterus usually reaches distinctly posteriorly to testes. The eggs are small. The follicular vitellarium is in 2 small fields just anterior to testes. The ventrally subterminal excretory pore leads to a claviform vesicle. This species does not fit clearly into any known family of digeneans and is placed in the Macroderoididae as a temporary measure. Other digeneans reported from Lake Malawi include Haplorchoides cahirinus (Looss, 1896) in C. mossambicus and B. meridionalis; Astiotrema turneri Bray, van Oosterhout, Blais & Cable, 2006 in Protomelas annectens, P. cf. taeniolatus, Labeotropheus fuelleborni, Ctenopharynx (Otopharynx) pictus, and Pseudotropheus zebra; Glossidium pedatum Looss, 1899 in C. mossambicus and B. meridionalis; and an unidentifiable sanguinicolid from Bathyclarias nyasensis.  相似文献   

19.
A new peritrichous ciliate, Zoothamnium palmphlatum nov. spec., was collected from an estuary in Yantai, China. It was investigated, using both live observation and silver staining. The new species can be identified by a palm‐shaped colony consisting of highly developed and alternately arranged secondary branches, a double‐layered peristomial lip, and an infundibular polykinety 3 composed of two parallel kinetosomal rows. Phylogenetic analyses of the small subunit (SSU) rRNA gene sequence show that Z. palmphlatum clusters with other members of the family Zoothamniidae. Furthermore, the comparison of primary and secondary SSU rDNA structures indicates that Z. palmphlatum is distinctly different from its morphologically similar species (93.2–97.0% in sequence similarity) in combination of H10 and H31 regions. Although Zpalmphlatum shares highest sequence similarity with Zoothamnium mucedo (98.9%), the new species has distinctly different structures in the H11, H12, H18, and H31 regions compared to Z. mucedo, which indicates that sequence similarity may not determine the similarity of the secondary structure.  相似文献   

20.
A new species of Orchidaceae, Calanthe yaoshanensis Z. X. Ren & H. Wang from northeastern Yunnan, China, is described and illustrated. It is morphologically similar to C. brevicornu Lindley, from which it differs by having a glabrous column and an elliptical middle lobe with three triangular lamellae. The morphological differences between C. yaoshanensis and related species are discussed. The habitat was investigated and its conservation status was assessed as a ‘Critically Endangered’ (CR).  相似文献   

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