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1.
This study describes a new species of Gieysztoria found in lentic environments in Argentina. Gieysztoria falx sp. n. appears to be closely related to G. therapaina and G. intricata , and is differentiated principally by the presence of two strongly developed pincer-shaped spines of the cuticular stylet. A preliminary analysis of the phylogeny among the South American species of this genus is undertaken, and the monophyly verified. This study constitutes the first approach to interpreting these relationships.  相似文献   

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Three new species and two new genera of Typhloplanoida from the Western Indian Ocean are described. Feanora brevicirrus gen. et.sp. n. is a member of the Trigonostomidae von Graff, 1905 sensu Den Hartog, 1964. It has a cirrus, paired ovovitellaria and an undifferentiated afferent duct. An excentric bursa opens in the fecundatorium and a large ovoid vesicle enters the afferent duct in its distal part. Gaziella pileola gen. et sp. n. and G. lacertosa sp.n. are two new members of the Promesostomidae Den Hartog, 1964. They have a long cirrus, ovovitellaria and a long muscular female duct with two excentrically placed sperm-receiving vesicles. Their most striking feature is the proboscis-like structure. Feanora and Gaziella are provisionally considered as genera incertae sedis within the resp. families.  相似文献   

4.
Twelve new species of Polycystididae Graff, 1905 are described from the Australian east coast. Nine of them could not be placed in any of the existing genera, and therefore six new genera are erected. Alchoides n. gen. differs from all other polycystidid genera by the presence of a bundle of glands that opens into the distal part of the male atrium (accessory vesicle type V). Two species are included in the genus, A. alchoides n. sp. and A. dittmannae n. sp., which differ from each other in the shape of the stylet. Ametochus gehrkei n. gen n. sp. can be distinguished from other polycystidids by the presence of a prostate vesicle type III associated with a prostate stylet type III, combined with the presence of an accessory stylet type III, while a prostate stylet type II is lacking. Typical for Arrawarria inexpectata n. gen n. sp. is the combined presence of an armed cirrus with a prostate vesicle type II connected to a prostate stylet type II. Two species are assigned to the new genus Duplexostylus n. gen.: D. rowei n. sp. and D. winsori n. sp. These two species have two unique features: a prostate vesicle type IV directly connected to a prostate stylet type III and an asymmetrical septum that surrounds the proximal part of the male atrium. They can be distinguished from each other by differences in the detailed construction of their stylets. Two new species are placed in the new genus Stradorhynchus n. gen.: S. caecus n. sp. and S. terminalis n. sp. They have unpaired gonads and a prostate vesicle type IV connected to a prostate stylet type IV, which combination of characters makes them unique within the Polycystididae. The two species differ from each other in the shape and size of the stylet. Triaustrorhynchus armatus n. gen., n. sp. is the first species of the Polycystididae to have three types of stylet in the male atrium: a prostate stylet type II, a prostate stylet type III and an accessory stylet type III. Three new species could be placed in existing genera: Cincturorhynchus monaculeus n. sp., Paraustrorhynchus caligatus n. sp. and Polycystis australis n. sp. All three differ from their congeners in the form and dimensions of their stylets. All newly described species are discussed, giving their similarities and differences with resembling species. Austrorhynchus hawaiiensis Karling, 1977 is reported for the first time in Australia, and the Australian population is compared with populations from other regions. The presence of Gyratrix hermaphroditus Ehrenberg, 1831, one new species of Paulodora Marcus, 1948 and a new genus of Typhlopolycystidinae Evdonin, 1977 is mentioned.  相似文献   

5.
Two new species of Dalyellidae, Dalyellia callvucurai n. sp. and Gieysztoria namuncurai n. sp., are described from temporary freshwater environments in central Buenos Aires Province, Argentina. The ultrastructure of the stylets of both species is also described. The new species of the genus Dalyellia is the second species of the genus found in the neotropics and the first whose stylet has been studied with scanning electron microscopy. Gieysztoria namuncurai n. sp. joins the seven species of the genus known in Argentina. The ultrastructural characteristics of the stylet place it in the Inaequales group, with complex stylets.  相似文献   

6.
A new species of Aequales group,namely Gieysztoria shiyanensis Wang Xia,sp.nov.,is described from China.The new species is diagnosed by a sclerotic stylet with a belt attaching 15 fang-like spines.A worldwide list of Aequales group and a key to species of Gieysztoria in China are provided.  相似文献   

7.
Two new turbellarian species, Gieysztoria shantouensis Zhang, Li Wang, sp. nov. and G. huizhouensis Zhang, Wu Wang, sp. nov. are described, which were collected from ditches in Shantou and Dongjiang River, Huizhou of Guangdong Province, respectively. G. macrovariata(Weise, 1942) was firstly recorded in China. All specimens examined were deposited in National Zoological Museum, Institute of Zoology, Chinese Academy of Sciences, China.  相似文献   

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Dalyellida represents a taxon of small rhabdocoel flatworms that occur in freshwater habitats all over the world. Combining histology and electron microscopy we have analyzed the embryonic development of a new dalyellid species, Gieysztoria superba, in order to obtain more comparative data pertaining to morphogenesis and organogenesis in flatworms. We have used a morphological staging system that we recently introduced for another rhabdocoel, Mesostoma lingua (Younossi-Hartenstein et al., 2000). Our data show that in many fundamental respects, such as the irregular cleavage, mesenchymal embryonic primordium, and lack of gastrulation movements, Gieysztoria is highly similar to Mesostoma. During cleavage (stages 1 and 2) the embryo is located in the center of the egg where it is surrounded by a layer of yolk cells. Cleavage leads up to a solid, disc shaped cell cluster. During stage 3, the embryo migrates to the ventral side of the egg and acquires bilateral symmetry. Stages 4/5 sees the emergence of the first organ primordia, the brain, epidermis and pharynx. A peculiar invagination of the epidermal layer pushes the embryo back into the center of the yolk ("embryonic invagination"). Organogenesis takes place during stages 5 and 6 while the embryo is invaginated. A junctional complex, consisting initially of small septate junctions, followed later by a more apically located zonula adherens, is formed in all epithelial tissues, including epidermis, protonephridia, and pharynx. During late stages (6-8), Gieysztoria embryos evert back to the surface where the epidermal primordium expands and grows around the yolk to close dorsally. During this phase of development cytodifferentiation of the different organ systems takes place. Stage 7 is characterized by the appearance of eye pigmentation, brain condensation and spindle shaped myocytes. Stage 8 describes the fully dorsally closed and differentiated embryo. In comparison to other rhabdocoels, including Mesostoma, Gieysztoria exhibits a precocious differentiation of an intestinal epithelium and male genital apparatus. In Mesostoma, these structures are formed post hatching.  相似文献   

10.
GieysztoriaRuebush and Hayes, 1939, the most species-rich genus of limnic rhabdocoels (Platyhelminthes: Dalyelliidae), is subdivided into several groups based on stylet morphology. Most taxa are known from the Palearctic and the Neotropics. Very little is known about limnic, free-living flatworms in other tropical and subtropical regions. In this contribution five new species of Gieysztoria are described from India, Australia and South Africa, all former Gondwanan fragments. Gieysztoria garudae n. sp., G. ashokae n. sp. and G. ramayana n. sp. were collected in Goa (India), G. stokesi n. sp. in the Northern Territory (Australia) and G. zuluensis n. sp. in KwaZulu-Natal (South Africa). All these new species share a typical, very complex stylet morphology, which deviates strongly from that of the groups into which the bulk of the other species within this genus are classified. Therefore a new subgroup, the “Falcatae”, is erected. In addition, four known species could also be included in this subgroup. Possible homologies, common ancestry and biogeographic distribution patterns are discussed.  相似文献   

11.
The study of gill and skin parasites of three fishes species belonging to the genus Clarias: C. camerunensis, C. jaensis and C. pachynema, from the Nyong basin (Cameroon), revealed the presence of two new Monogenean species of the genus Gyrodactylus Nordmann: G. camerunensis n. sp. and G. nyongensis n. sp. parasite of Clarias camerunensis, C. jaensis and C. pachynema. Gyrodactylus camerunensis n. sp. is clearly distinguished from G. nyongensis n. sp. by the smaller size of the haptor sclerites. These two new species differ also from their closest African relatives of the genus Gyrodactylus, G. rysavyi, G. clarii and G. alberti, by the morphology and size of the haptorail sclerites. Their host specificity was discussed and appeared stenoxenous (mesostenoxenous).  相似文献   

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Abstract

A new species of nematode, Heth baudini sp. n. from a diplopod (Spirostreptida: Iulomorphidae Verhoeff, 1924) collected in Queensland, Australia, is described and illustrated. The cephalic and cervical cuticular ornamentation of females of H. baudini sp. n. is similar to those of South-East Asian and Australasian Heth species. Heth baudini sp. n. females are particularly close to Heth taynguyeni from Vietnam but can be distinguished by the shape of the lateral lappets, which in H. taynguyeni limit the trapezium-shaped region of smooth cuticle unlike the elliptical region in H. baudini sp. n., and by the presence of lateral spines only half the size. The cuticle of the H. baudini sp. n. is finely annulated along the entire body, whereas H. taynguyeni has broader rings behind the first pair of lateral spines, each consisting of five or six narrower rings separated from each other by deeper furrows. Males of H. baudini sp. n. are characterised by the presence of a bursa-like fold on the tail and can be distinguished from other species of the genus by the presence of somatic papillae embedded into the bursal fold.  相似文献   

14.
Molecular studies of the Capsalidae suggested that the genus Benedenia is polyphyletic, but a taxonomic organization of the genus that reflects molecular data has not yet been proposed. As a result of molecular analysis (28S rDNA, ITS1–5.8S-ITS2, and cox1 data) including specimens of Benedeniinae newly obtained from Okinawa-jima Island in Japan, two new genera and the revival of Tareenia independent to the genus Benedenia are proposed. Gracilobenedenia n. gen. is distinguished from the other genera of Benedeniinae based on morphological characteristics. This new genus comprises 6 species: G. lutjani n. comb. (type species), G. anticavaginata n. comb., G. rohdei n. comb., G. beverleyburtonae n. comb., G. kuremibai n. gen., n. sp., and G. hichi n. gen., n. sp. Armatobenedenia n. gen. is a monotypic genus for A. armata n. comb. The present molecular phylogenetic analysis showed the independence of Tareenia, and it can be morphologically separated from the other benedeniines. Four species including two new species obtained from Okinawa-jima Island are reported: G. kuremibai n. sp., G. hichi n. sp., G. lutjani n. comb., and Metabenedeniella parva. Furthermore, in the species identification and phylogenetic analysis of capsalids, the usefulness of not only the 28S rDNA but also ITS and the cox1 regions was suggested. These genes were evaluated the efficacy of those regions in DNA barcoding, and the ITS and cox1 regions shown to be useful for DNA barcoding in capsalids compared to the 28S rDNA sequence.  相似文献   

15.
Four nematode species of the Comesomatidae from the Strait of Magellan and the Beagle Channel, Chile, are described as new to science. Comesoma hermani n. sp. can be separated from similar species, Comesoma bermudense Jensen & Gerlach, 1977, Comesoma minimum Chitwood, 1937 and Comesoma chilense Jensen & Gerlach, 1977 by the difference of body length, cephalic setae length, the ratio of the subcephalic setae to cephalic setae length and the ratio of spicule to anal body diameter. Dorylaimopsis magellanense n. sp. is identified by the lateral differentiation of 3–4 longitudinal rows of enlarged dots, the curved spicules are prominently jointed and with a ventral protrusion. Hopperia beaglense n. sp. could be easily recognised by both the rounded tail tip and anterior head end which differs from all the species of this genus except H. dorylaimopsoides (Allgén, 1959), which has, however, a smaller de Man ratio 'a' and reflexed ovaries. Hopperia arntzi n. sp. has a shorter body length which differs from the closest species, Hopperia americana Ward, 1984 and Hopperia muscatensis Warwick, 1973. Furthermore, the de Man ratio 'a' is different between our specimens and the other two species. An identification key to all known species of the genus Hopperia is provided.  相似文献   

16.
报道了在云南西南部发现的凤仙花属一新种——滇红凤仙花(Impatiens quintadecimacopii G.W.Hu&Q.F.Wang)和一新记录种——伸展凤仙花(I.porrecta Wall.ex Hook.f.&Thomson)。这两个种在形态上很相似,但在花色、侧萼片形状、旗瓣形状和蒴果颜色上明显有别。根据形态特征,这两个种应属于凤仙花亚属(I. subg.Impatiens)单花组(I. sect.Uniflora)。结合核糖体DNA内转录间隔区序列(ITS)与叶绿体atpB-rbcL间隔区序列开展系统发育分析,结果进一步确认了这两个种关系紧密,以及它们在单花组内的系统位置。  相似文献   

17.
Ancilibracon gen.n. (type species: Ancilinracon townesi sp.n.). Ancilibracon bakeri sp.n., Gelasinibracon gen.n. (type species: Gelasinibracon sedlaceki sp.n.), Gelasinibracon simplicicaudatus sp.n., Esengoides gen.n. (type species: Esengoides crentdatus sp.n.) and Esengoides fulvus sp.n. are each described and illustrated. Ancilibracon towensi is from Malaysia. A. bakeri is from Borneo, both Gelasinibracon species are from Guinéa, E. crenulatus is from the solomon Islands and E. fulvus is from Australia. These three new genera belong to the Plesiobrscon Cameron group of the Braconina. Their relationship are discussed.  相似文献   

18.
Three new species of lung-dwelling nematodes are described from the frogs Ptychadena anchietae (Bocage), P. oxyrhynchus (Smith), and P. uzungwensis (Loveridge) in southern Africa. All three species are medium-sized species of Rhabdias Stiles et Hassall, 1905, with the thick-walled buccal capsules measuring 11–13 μm × 6–11 μm, consisting of longer anterior and shorter posterior parts. Rhabdias athos n. sp. and R. porthos n. sp. are characterised by the rounded anterior end of the body and the presence of short dilatation of the oesophagus at its mid-length. Rhabdias porthos n. sp. has distinct excretory glands which are absent in two other species. Rhabdias aramis n. sp. is characterised by the truncated anterior end and the slight constriction of the oesophagus at the level of its mid-length. Phylogenetic analysis based on ITS-28S rDNA sequences placed R. aramis n. sp. in the clade consisting of R. engelbrechti Kuzmin et al., 2017 from South Africa and Eurasian Rhabdias spp., while R. athos n. sp. and R. porthos n. sp. formed a sister group to that clade. Identification key to 14 Rhabdias spp. parasitic in anuran amphibians from the Afrotropical Realm is provided.  相似文献   

19.
First Report on Marine Microturbellarians from Hawaii   总被引:4,自引:0,他引:4  
Karling, T. G. (Section of Invertebrate Zoology, Swedish Museum of Natural History, Stockholm, Sweden), Valeria Mack-Fira, and Jürgen Dörjes. First report on marine microturbellarians from Hawaii. Zool. Scripta 1 (6): 251–270, 1972.–The material presented here consists of: Cilionema hawaiiensis gen. et sp. n., Microvahine corallicola gen. et sp. n., Archiloa subtilis sp. n., Minona bistylifera sp. n., Duplominona kaneohei sp. n., Archimonocelis heljrichi sp. n., Ulelga variodentata sp. n., Notocelis gullmarensis maculata ssp. n., Cylindrcstoma monotrochum (Graff), Plagiostomum acoluthum Marcus, Gyratrix hermaphroditus Ehrenberg and Austrorhynchus pectatus Karling. The anatomy of the species is described and their taxonomy discussed. Views are given on the comparative anatomy of the bursal organs. The ecology and the biogeography of the species are briefly discussed.  相似文献   

20.
Two new Rhabdocoel species from the Peruvian Amazonia are described: Sergia calae n. sp. (Dalyelliidae) and Mesostoma ucamara n. sp. (Typhloplanidae). Both species were captured in the Pacaya-Samiria National Park, Loreto, Peru, with plankton-nets dragged several times through the abundant littoral floating plant-community. This is the first record of micro-turbellarians in this region. The discovery of these new species in the Pacaya-Samiria National Park suggests the high diversity of this area, which up to now has remained largely unknown, increases the general knowledge of the fauna of Neotropical turbellarians.  相似文献   

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