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1.
Summary A new species of Ergasilus is described and illustrated from the gills of juvenile ( c. 70 mm total length) Siganus guttatus raared in a Philippine fish farm. Of 15 fish examined, all were infested and nine had concurrent lymphocystis infections. ac]19820901 相似文献
2.
Four new species of Acusicola are described based on adult females found on gill filaments of several species of coastal and freshwater fishes caught in Brazilian basins. The distribution area of the genus in Brazil is significantly enlarged, since until now the previous Brazilian species had been known only from Amazonian fishes. The specimens identified as Acusicula tenax by Cressey and Collette (1970) are considered representatives of a new species, A. rogeri. A key for identification of the species of Acusicola is provided. 相似文献
3.
The growing body of empirical evidence for sympatric speciation has been complemented by recent theoretical treatments that have identified evolutionary conditions conducive to speciation in sympatry. The Neotropical Midas cichlid (Amphilophus citrinellum) fits both of the key characteristics of these models, with strong assortative mating on the basis of a colour polymorphism coupled with trophic and ecological differentiation derived from a polymorphism in their pharyngeal jaws. We used microsatellite markers and a 480 bp fragment of the mitochondrial DNA control region to study four polymorphic populations of the Midas cichlid from three crater lakes and one large lake in Nicaragua in an investigation of incipient sympatric speciation. All populations were strongly genetically differentiated on the basis of geography. We identified strong genetic separation based on colour polymorphism for populations from Lake Nicaragua and one crater lake (Lake Apoyo), but failed to find significant genetic structuring based on trophic differences and ecological niche separation in any of the four populations studied. These data support the idea that sexual selection through assortative mating contributes more strongly or earlier during speciation in sympatry than ecological separation in these cichlids. The long-term persistence of divergent cichlid ecotypes (as measured by the percentage sequence divergence between populations) in Central American crater lakes, despite a lack of fixed genetic differentiation, differs strikingly from the patterns of extremely rapid speciation in the cichlids in Africa, including its crater lakes. It is unclear whether extrinsic environmental factors or intrinsic biological differences, e.g. in the degree of phenotypic plasticity, promote different mechanisms and thereby rates of speciation of cichlid fishes from the Old and New Worlds. 相似文献
4.
Systematic Parasitology - A new parasitic copepod, Ergasilus yandemontei n. sp., is described based on 10 adult females collected from the gills of the atherinid silverside Odontesthes hatcheri... 相似文献
5.
Primula jiugongshanensis J. W. Shao, a new species from Mt Jiugongshan in Hubei Province, China, is described and illustrated. This species is a biennial glabrous herb with pinnately compound leaves, and affiliated to P. sect. Ranunculoides C. M. Hu. It is distinguished from other species of the section by outer simple leaves ovate, flowers distylous, corolla lobe apex conspicuously emarginate, and lack of bulblets. Molecular phylogenetic analysis of nrDNA internal transcribed spacer sequences (ITS) was conducted and the results also supported the recognition of P. jiugongshanensis as a new species. The species is known from only three separated unprotected populations and is categorized as ‘Endangered’ (EN). 相似文献
6.
Summary A new species of notodelphid copepod infesting the solitary ascidian Rodosoma turcium (Savigny, 1816) from the Gulf of Cariaco, Venezuela, is described and illustrated. This is the first record of Lonchidiopsis Vanhöffen. 1917, from the Caribbean. ac]19801201 相似文献
7.
Pomphorhynchus patagonicus n. sp. is described from Lake Rosario, Chubut Province, Argentina. It is characterized by a long neck forming an asymmetrical bulb with 2 well differentiated dorsal protruberances and 14 alternating rows of 13 and 14 proboscis hooks, each row with a stout fourth hook. It most closely resembles Pomphorhynchus sebastichthydis Yamaguti, 1939, from Japan, but differs in the bulb protruberances and in having more rows of hooks and more hooks per row and in the shapes of the fourth and basal hooks. Among American species P. patagonicus shows some similarities to Pomphorhynchus yamagutii Schmidt and Hugghins, 1973, from Chile, but differs with respect to the longer neck, bulb protruberances, and proboscis armature. Pomphorhynchus patagonicus is endemic to Patagonia, where its definitive type host is the endemic fish Patagonina hatcheri (Atherinidae) and its intermediate host the endemic freshwater amphipod Hyalella patagonica. It has been found also in autochthonous fishes belonging to the families Galaxiidae and Percichthyidae and in introduced salmonid fishes. 相似文献
8.
Eudiaptomus anatolicus n.sp. displays similarity to E. transylvanicus (Daday, 1890) by possessing an outer marginal spine
located proximally on the second exopodite segment of the male right P 5, but it differs from this closest species in the presence of a chitinous projection on the second exopodite segment of the
male right P 5, and in the typical shape of the female's thoracic wings. E. transylvanicus (Daday, 1890) has three chitinous processes located
on the basipodite segment of the male right P 5, whereas Eudiaptomus anatolicus n.sp. has only one small process on this part.
This new species is living in lake Poyraz, which is small and shallow. Some cladoceran species, namely, Pleuroxus truncatus
(O.F. Müller, 1785), Pleuroxus laevis (Sars, 1862), Pleuroxus trigonellus (O.F. Müller, 1785), Simocephalus exspinosus (Koch,
1841), Eurycercus lamellatus (O.F. Müller, 1785), Alonella excisa (Fischer, 1854), Lathonura rectirostris (O.F. Müller, 1785),
Pseudochydorus globosus (Baird, 1843) and two cyclopoid copepods, Megacyclops viridis (Jurine, 1820) and Eucyclops serrulatus
(Fischer, 1851) share the same habitat.
This revised version was published online in July 2006 with corrections to the Cover Date. 相似文献
9.
A new species of parasitic copepod, Echthrogaleus spinulus n. sp. (Pandaridae), is described from the torpedo ray Tetronarce tokionis (Tanaka) (Torpedinidae) captured in pelagic Hawaiian waters. The new species has pediger 4 bearing large dorsal plates with denticles on posterior margin, genital complex with posterolateral lobes widely curved medially and overlapping, leg 4 exopod incompletely 3-segmented, and the largest body size (maximum length 16 mm from anterior rim of frontal plates to tip of caudal rami, excluding setae). This morphology does not match any of the seven valid species of Echthrogaleus Steenstrup & Lütken, 1861. Analysis of 28S rDNA sequences separated the new material from the Central Pacific from samples of E. coleoptratus in the Atlantic and Eastern Pacific Oceans. However, due to the lack of DNA sequences in the databases, the new 28S rDNA sequence cannot used to confirm the species identity. The unique morphological characteristics of the Central Pacific female copepods combined with 28S rDNA sequencing was used as a basis to validate the new species. 相似文献
10.
Bomolochus peruensis n. sp., a parasite of the sciaenid fishes Menticirrhus ophicephalus and Sciaena deliciosa from the central Peruvian coast, is described and illustrated. The new taxon differs from all other Bomolochus species in a combination of characteristics of leg 2, leg 4 and leg 6 and by the presence of spinules on the ventral surface
of the last abdominal segment only. This is the first record of Bomolochus from South America. 相似文献
11.
A new species of Neodiaptomus, N. intermedius n. sp. is described and illustrated. It is compared with related species of the strigilipes — physalipus species group. 相似文献
12.
Halosarpheia unicellularis sp. nov. is described from decayed attached wood of Avicennia marina collected from two mangrove sites in the Red Sea, Egypt. The ascomycete is compared with other marine taxa having ascospores
with polar unfurling appendages. It is also compared with other marine genera with oval, round or ellipsoid hyaline, unicellular
ascospores, but for which appendages have not been reported. Molecular data confirms the assignment of the fungus to Halosarpheia which forms a clade with the type species Halosarpheia fibrosa. 相似文献
13.
A new species of Bryocamptus from North America, B. pilosus n. sp., is described and illustrated. Some remarks are made on the occurrence of a specific piliform seta on the ventral side of the caudal ramus in the vejdovskyi species group. 相似文献
14.
Agapophytinae subf.n. is a highly diverse lineage of Australasian Therevidae, comprising eight described and two new genera: Agapophytus Guérin‐Méneville, Acupalpa Kröber, Acraspisa Kröber, Belonalys Kröber, Bonjeania Irwin & Lyneborg, Parapsilocephala Kröber, Acatopygia Kröber, Laxotela Winterton & Irwin, Pipinnipons gen.n. and Patanothrix gen.n. A genus‐level cladistic analysis of the subfamily was undertaken using sixty‐eight adult morphological characters and c. 1000 base pairs of the elongation factor‐1α (EF‐1α) protein coding gene. The morphological data partition produced three most parsimonious cladograms, whereas the molecular data partition gave a single most parsimonious cladogram, which did not match any of the cladograms found in the morphological analysis. The level of congruence between the data partitions was determined using the partition homogeneity test (HT F) and Wilcoxon signed ranks test. Despite being significantly incongruent in at least one of the incongruence tests, the partitions were combined in a simultaneous analysis. The combined data yielded a single cladogram that was better supported than that of the individual partitions analysed separately. The relative contributions of the data partitions to support for individual nodes on the combined cladogram were investigated using Partitioned Bremer Support. The level of support for many nodes on the combined cladogram was non‐additive and often greater than the sum of support for the respective nodes on individual partitions. This synergistic interaction between incongruent data partitions indicates a common phylogenetic signal in both partitions. It also suggests that criteria for partition combination based solely on incongruence may be misleading. The phylogenetic relationships of the genera are discussed using the combined data. A key to genera of Agapophytinae is presented, with genera diagnosed and figured. Two new genera are described: Patanothrix with a new species ( Pat. skevingtoni) and Pat. wilsoni (Mann) transferred from Parapsilocephala, and Pipinnipons with a new species ( Pip. kroeberi). Pipinnipons fascipennis (Kröber) is transferred from Squamopygia Kröber and Pip. imitans (Mann) is transferred from Agapophytus. Agapophytus bicolor (Kröber) is transferred from Parapsilocephala. Agapophytus varipennis Mann is synonymised with Aga. queenslandi Kröber and Aga. flavicornis Mann is synonymised with Aga. pallidicornis (Kröber). 相似文献
15.
A new nematode, Pseudocapillaria (Discocapillaria) margolisi n. subg., n. sp., from the freshwater fishes Puntius conchonius, P. sophore and Amblypharyngodon mola of West Bengal, India is described. The presence of a ventral lobe-like elevation with two papillae and the absence of a dorsal cuticular membrane on the male tail are referred to as distinguishing features of the new subgenus. The parasite is also characterised by small body size, short and non-annulated stichocytes, a distinctly expanded and folded lobular rim of the proximal end of the spicule, and eggs with protruding polar plugs, all features in which it differs distinctly from other species of the genus Pseudocapillaria. 相似文献
16.
Jusheyhoea moseri (Copepoda, Chondracanthidae), a new species parasitic on deep water fishes off Hawaii, is described and illustrated. It differs from its only congener in the size and number of its trunk processes, as well as in the positions of its two pairs of legs. The latter differences necessitated redefinition of the genus Jusheyhoea. A new generic diagnosis is appended and the taxonomic value of some morphological characteristics of chondranthids is discussed. 相似文献
17.
A new anisakid nematode, Hysterothylacium patagonense n. sp., is described from the intestine of the temperate bass Percichthys trucha (Cuvier & Valenciennes), a freshwater fish from Lake Aluminé, Patagonia, Argentina. It is characterised mainly by the absence of lateral alae, the length ratio of the caecum and ventricular appendix (1:0.9–1.8), the length of the spicules (0.952–1.292 mm) and the presence of minute spines on the tip of the tail. In the same locality and in Lake Huechulafquen, advanced third-stage and fourth-stage larvae of this parasite were also recorded from the digestive tract of the introduced salmonids, Salvelinus fontinalis (Mitchell), Oncorhynchus mykiss (Walbaum) and Salmo trutta L. This is the second Hysterothylacium species described from freshwater fishes in South America. A key to Hysterothylacium species parasitising American freshwater fishes is provided. 相似文献
18.
The female of Ergasilus thatcheri n. sp. (Copepoda, Poecilostomatoida, Ergasilidae) is described from the gills of the "jundiá," Rhamdia quelen (Teleostei, Siluriformes, Pimelodidae), from fish ponds in the State of Rio Grande do Sul, Brazil. The new species has a falciform semipinnate terminal seta on the first exopod, which suggests phylogenetic affinity to 10 other congeners, all from fishes of the Amazon Basin. Based on general morphology, the new species shows great similarity to E. callophysus Thatcher and Boeger, 1984, a parasite of another pimelodid fish Callophysus macropterus. Ergasilus thatcheri n. sp., however, can be easily differentiated from E. callophysus in its possession of a more distal sensillum not located on a cuticular elevation, and a row of spinules on the inner margin of the second antennal segment (first endopodal segment). 相似文献
20.
Phyllodiaptomus praedictus n. sp. is described from the Bangkok area. It might be endemic to Thailand. It belongs to the blanci-group of species, and is most closely related to P. annae and P. wellekensae. 相似文献
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