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1.
Steganoderma szidati n. sp. is described from the intestine of two freshwater fishes, Galaxias maculatus and G. platei (Galaxiidae), from Andean lakes in Patagonia, Argentina. This freshwater zoogonid species fits in the genus Steganoderma (sensu Bray, 1987) because of the length of the caeca and the position of the vitelline follicles. The new species is characterised by possesing 6-13 vitelline follicles situated between the anterior margin of the ventral sucker and the poterior margin of the testis. The gonads are in the anterior hindbody and the ovary is anterior to the right testis. The cirrus has two conspicuous spines at its distal end, and the seminal vesicle always exhibits a constriction. The excretory vesicle never reaches the level of the posterior margin of the testes.  相似文献   

2.
Using independently segregating nuclear single nucleotide polymorphisms (SNPs) and mitochondrial control region sequences, we found an east–west division among sampled willow grouse Lagopus lagopus subspecies. This division cut across the range of the subspecies with the largest distribution (lagopus) and thus contradicted existing taxonomic classifications. Russian Lagopus lagopus lagopus tended to cluster with North American willow grouse partly classified as other subspecies. Scandinavian willow grouse (L. l. lagopus) clustered with red grouse from Britain and Ireland (Lagopus lagopus scoticus and Lagopus lagopus hibernicus) but substructuring confirmed the monophyly of the latter. In North America, we could not detect any major genetic divisions apart from two birds described as alexandrae from the Heceta Island (Alaska) when using mitochondrial sequences. Other samples from North America were intermingled regardless of whether they were described as muriei, alexandrae or lagopus. A specimen described as alexandrae was to some extent distinct when analysing the SNP data. The genetic analyses indicated some concordance between genetics and taxonomy but not complete congruence. This is particularly evident for mitochondrial DNA network analyses. We suggest that the taxonomy of this species would benefit by a careful re‐examination of the available evidence for subspecies. It appears as if subspecies status is a poor proxy for assigning evolutionary significant units and management units in this species. © 2013 The Linnean Society of London, Biological Journal of the Linnean Society, 2013, 110 , 77–90.  相似文献   

3.
Summary Sobolevicanthus transvaalensis n.sp. is described from the Cape Teal, Anas capensis Gmelin, 1789, collected in the Republic of South Africa. The new species possesses 8 skrjabinoid hooks 78–88 m long (mean 85 m) and a short claviform cirrus-sac 79–143 m long and resembles S. javanensis (Davis, 1945) and S. terraereginae (Johnston, 1913). It can be distinguished from S. javanensis by its shorter cirrus-sac and smaller cirrus diameter, and by differences in the morphology of the accessory sac and vagina and in their position relative to the cirrus-sac. It can be separated from S. terraereginae on the basis of cirrus length and diameter. The basal diameter of the cirrus in S. terraereginae is three times that in S. transvaalensis. ac]19830414  相似文献   

4.
Summary Ogmogaster heptalineatus n.sp. is described from the Chilean sea lion Otaria flavescens. Distinct characteristics of the species are: presence of 7 longitudinal ridges on the ventral surface, cirrus armed with scales, testes and ovary deeply lobed and eggs circular with short polar filaments. This is the first report of the genus Ogmogaster from South America and the first report of Otaria flavescens as a host for this genus. ac]19820320  相似文献   

5.
Onchobothrium malakhovi n. sp. was found in the spiral valve of the softnose skate Bathyraja (Arctoraja) sexoculata off the Simushir Island (Kuril Islands, Russia). The new species has bothridia with three loculi and no additional suckers on bothridia, single-toothed hooks unconnected by their bases, no spines at the bases of the hooks, dense matrix around the hook bases shaped as an unpaired butterfly wing, and a short and wide ovary. Onchobothrium malakhovi n. sp. differs from O. antarcticum and O. magnum in having a smaller total length, cirrus sac and ovary, smaller testes and eggs. Additionally, the new species differs from O. antarcticum by the absence of a vaginal sphincter and shorter bothridia; differs from O. magnum in having fewer proglottids and smaller vitelline follicles. It differs from O. farmeri, O. convolutum, and O. pseudouncinatum, by the absence of a small spine at the base of the hooks and the absence of accessory suckers on bothridia; from O. pseudouncinatum, additionally, by unconnected hooks; from O. schizacanthium, by the number of testes and by the presence of a postvaginal group of testes. Onchobothrium malakhovi n. sp. was placed among other members of the Onchoproteocephalidea with a high support based on the sequence data for the D1-D3 region of the 28S rDNA and cox1 gene. The phylogenetic position of the genus Onchobothrium sensu lato remains ambiguous. We suggest that Onchobothrium sensu lato is a complex genus containing at least two morphologically different groups of species. Onchobothrium farmer, O. convolutum, O. schizacanthium, and O. pseudouncinatum, for which there are no molecular genetic data, are considerably different morphologically from O. malakhovi n. sp., O. antarcticum, and O. magnum. A new genus might have to be established for the latter three species after the accumulation of genetic data.  相似文献   

6.
Nadejdolepis bealli n. sp. a parasite from Calidris alpina in Alaska (USA), is described and illustrated. It is 3-4 cm long and has: rostral nitiduloid hooks 95-96 m long, with the blade a little longer than the handle; three testes in a symmetrical triangle; a cirrus-sac 175 m long, not crossing the median line; a cirrus borne on an unarmed basal bulb, 25 m long when evaginated, and armed with numerous, compact and very thin spines 1 m long; a short (25 m) membranous and tubular vagina with neither a sclerotinoid section nor a sphincter; and a pyriform seminal receptacle. The species is differentiated from the other species of the genus with rostral hooks of comparable length by the configuration of the male and female genital ducts; they have no equivalent particularly in the shortness of the evaginated cirrus and the type of spines with which it is armed. Mention is also made of the presence of Nadejdolepis paranitidulans (Golikova, 1959) and Wardium amphitricha (Rudolphi, 1819) from the same host in Alaska.  相似文献   

7.
Two new species of Eurycestus Clark 1954 are described from the American avocet Recuruirostra americana Gmelin 1788. Eurycestus is a genus of disproportionately wide cestodes in which suckers and rostellum are apparently wanting and which have complete duplication of reproductive system in each segment. The new species E. falciformis and E. latissimus spp. nov. differ from E. avoceti Clark 1954; E. falciformis resembles E. avoceti as figured in Clark's (1954) plate I, E. latisrimus resembles E. avoceti as depicted in Clark's (1954) plate II, but the three species differ, the diagnostic characters being shape of the strobila, size of the cirrus-sac, number of testes and armature of the cirrus, the last mentioned being the most easily recognized constant differentiating character. E. latissimus measuring up to 33 mm broad, and less than 1 mm in length, has, in each side, 31–44 testes, a cirrus-sac 333–447 μm long by 45–47 μm in diameter and a cirrus with 14–16 longitudinal rows of strong rose-thorn-shaped spines, measuring 7 μm high; while E. falciformis, 12–20 mm wide by 1.7-2.4 mm long has, in each side, 27–35 testes, a cirrus-sac 355-320 μm long and 43-35 μm in diameter with a cirrus armed with 20–24 longitudinal rows of slender spines 4.5 μm long. In the holotype of E. avoceti the cirrus-sac measures 240–260 μm long by 55-51 μm in diameter and the cirrus is armed with over 40 longitudinal rows of minute spines 1.5-2 μm long. It also shows a reticulate uterus but the number of testes cannot be determined in it. A young avocet (R. auosetta) taken in the Camargue in the south of france was found by Baer (1968) to contain free, scolex-less strobilae which he identified as E. avoceti Clark in addition to separate scoleces embedded in the intestinal mucosa. He considered that the scoleces, dilepidid in type, belonged to the free strobilae, which if correct, adds to our knowledge of E. avoceti Clark and assigns this cestode to the Dilepidinae.  相似文献   

8.
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10.
Gyrodactylus quadratidigitus n. sp. (Monogenea, Gyrodactylidae) is described from the gills, fins and skin of Thorogobius ephippiatus (Lowe) (leopard-spotted goby) from Portland Castle Bay, Dorset, UK. G. quadratidigitus n. sp. most closely resembles the species ofGyrodactyluspreviously described by Geets from Pomatoschistus microps(Krøyer) in the approximate shape and size of the attachment hooks but can be readily distinguished from other species of the genus by the distinctive square shape of the toe region of the marginal hook sickle, the anteriorly positioned cirrus bulb and the unusually short intestinal crura which extend only as far as the level of the testes.  相似文献   

11.
A tendency for increase both of numerical and of ecological factors of infestation in pseudophyllid cestodes is realized due to morphological peculiarities of the structure of their reproductive system. In the species E. rugosum with the closed bursiform uterus and intrauterine development of eggs, there are revealed the same degree of maturity of oocytes in ovary, the lack of sphincter or filtering cell at the base of the ovicapt infundibulum, and the presence of a large vitelline reservoir. By analogy with trematodes, an interconnection is traced between the degree of egg maturation in the uterus and morphology of uterus and vittelicles. The thickening of the egg membrane has been shown to occur not only by deposits of individual vitelline globules at the internal superficial egg layer, but also by binding of lipid droplets excreted from the surrounding parenchyma to the uterine tube along its entire length to the external egg surface. The male reproductive system of Eubothrium rugosum is characterized by the presence of a small cirrus pouch, by the cirrus supplied with microtrichia, which corresponds to the similar vagina structure, and by localization of prostate glands outside the cirrus pouch. Comparison is presented with other ultrastructural peculiarities of organization of the reproductive system in the earlier studied species of pseudophyllid cestodes, Diphyllobothrium latum.  相似文献   

12.
The authors describe and illustrate two hymenolepidid cestodes parasitising Himantopus melanurus (Aves) from Paraguay. Microsomacanthus kaulobatroni n. sp., 20–30 long × 0.6 mm wide, with 10 diorchoid hooks 33–38 µm long, three testes in a transverse row, short cirrus 20–28 µm long armed with very minute spines, a short vagina with a sphincter, and a multi-lobed ovary, with genital ducts similar to those of Hymenolepis himantopodis ( sensu Fuhrmann, 1906) but with rostellar hooks different from those of Tænia himantopodis Krabbe, 1869 sp. inq. Wardium neotropicale n. sp., 40-50 long x 0.9 mm wide, has campanulate proglottides, scolex with 10 aploparaksoid rostellar hooks 9 µm long, testes arranged in a triangle, a short cirrus pouch without a transverse retractor muscle, very short, unarmed cirrus, a short vagina with a sphincter (30–35 µm in diameter) but no retractor muscle, a multi-lobed ovary and a bipartite uterus. The shape of the hooks distinguishes this species from T. himantopodis Krabbe, 1869 and other aspects of its anatomy from other species of Wardium with hooks of a similar size. A single specimen of a third Hymenolepis (sensu lato) species (lacking the scolex) could not be identified.  相似文献   

13.
Leporidotaenia n. g. is proposed for four cestode species parasitising Leporidae (Lagomorpha) which were previously considered as members of the genus Anoplocephaloides. The new genus is differentiated from Anoplocephaloides by the presence of a spinose covering on the tegument, the protrusible genital atrium, the massive cirrus-sac with highly developed musculature, the presence of a retractor muscle associated with the cirrus-sac, the posterior position of vaginal pore relative to the male orifice, the cirrus armed with long spines and its occurrence only in hosts of the family Leporidae (Lagomorpha). The genus includes: L. romerolagi (type-species), L. floresbarroetae, L. pseudowimerosa and L. wimerosa. the species (excluding L. floresbarroetae) are redescribed and figured and a differential key is presented. An attempt is made to explain the range of Leporidotaenia spp. in Central America and the western Palaearctic on the basis of the palaeozoogeography of rabbits and hares.  相似文献   

14.
Crocus cartwrightianus andC. cartwrightianus cv.albus pollen have been studied from structural and ultrastructural points of view and the germination assayed in vivo and in vitro.C. cartwrightianus pollen is regularly shaped and sized, has a low percentage of anomalous grains and has a high germination rate in vitro, whileC. cartwrightianus cv.albus is less regularly shaped with some variation in size and has a high percentage of anomalous grains and a low germination percentage in vitro. Ultrastructural observations have revealed, in the pollen of both the taxa, the presence of a thin elongated vegetative nucleus and a generative cell surrounded by a thin membrane. However,C. cartwrightianus pollen shows a thicker intine, andC. cartwrightianus cv.albus shows numerous pollen germination anomalies which are in common withC. sativus.  相似文献   

15.
Neoechinorhynchus (Neoechinorhynchus) dorsovaginatus n. sp. (Acanthocephala: Neoechinorhynchidae) is described from the dusky kob, Argyrosomus japonicus (Temminck & Schlegel) from the southern coast of South Africa in the Breede River Estuary. Like four other species of Neoechinorhynchus Stiles & Hassall, 1905, N. (N.) africanus Troncy, 1969, N. (N.) johnii Yamaguti, 1939, N. topseyi Podder, 1937 and N. (N.) tylosuri Yamaguti, 1939, the new species has a very long, slender body, cylindrical testes and cement-gland, anterior proboscis hooks much longer than the middle or posterior hooks, and a long neck. The new species is the only species of Neoechinorynchus having an antero-dorsal hump just posterior to the neck and a specialised vaginal sphincter and a gonopore on the dorsal side. It is closest to N. (N.) johnii, but is distinguished from it by: the size of the trunk, proboscis, anterior proboscis hooks, neck, and the posterior testis in relation to the cement-gland; the shape of cerebral ganglion and proboscis hook root; and the number of giant nuclei in the cement-gland.  相似文献   

16.
Sound production has been recently discovered in several species of Acipenser. Our work has focused on testing for sound production in species of sturgeon in the genus Scaphirhynchus. We discovered that pallid sturgeon Scaphirhynchus albus and shovelnose sturgeon, S. albus produce sounds during the breeding season. These signals may be used as part of efforts to localize populations of sturgeon in the field, including the Alabama sturgeon, S. suttkusi.  相似文献   

17.
Progamotaenia ruficola sp. n. is described from the red kangaroo (Macropus rufus) from New South Wales, Australia. It is distinguished from other similar species having paired, nondiverticulate uteri in each prolottis: Progamotaenia festiva (Rudolphi 1819), P. diaphana (Zschokke 1907), and P. macropodis Beveridge 1976, by the extremely broad, straight-edged velum, the lack of an external seminal vesicle, the cirrus armature, the number of testes, the lack of vaginal atrophy following insemination, and the morphology of the egg.  相似文献   

18.
The cat-fish Platydoras costatus (L.) is abundantly parasitised by the cestode genus Proteocephalus in Paraguay, previously unrecorded from this host. Morpho-metrical studies suggest the presence of two species, Proteocephalus soniae n. sp. and P. renaudi n. sp. They differ in the scolex, the distribution of the testes, the mean number of testes and uterine diverticula, the presence or absence of a vaginal sphincter, and the shape of the eggs and their envelopes. A single specimen, representing a possible third taxon, is morphologically similar to P. renaudi. Data from protein electrophoresis on amidon gel confirm the morpho-metrical conclusions. Of the 13 enzymes investigated, ACP, AAT, GPI and MDH have alleles of different electrophoretic mobilities in the three taxa. Only two alleles are distinguishable on locus HK. There is no evidence of heterozygotes in the tested systems. The specific status of the examined taxa is therefore confirmed. More material of the third species is required for establishing a species definition. P. renaudi has following unique anatomical features: the egg bears an enormous external envelope and an elongate embryophore with a unilateral appendix; the vitelline glands are paramuscular; and the eggs, laid in packets, are evacuated in an unusual way.The establishment of species based on protein electrophoresis allows a critical examination of the validity of anatomical characters usually used for taxonomic purpose. Good specific characters are the presence or absence of an apical organ and a vaginal sphincter and the relatively constant ratio between ovary width and the width of mature proglottids. The number of testes and uterine diverticula, both frequently used in species diagnoses, show variations which are often considerable and are, therefore, less unequivocal. The coefficients of variation observed calculating the mean numbers of testes can be high and reach up to 28%. This variation is itself a specific character in our opinion.
Etude morpho-anatomique et génétique de deux nouveaux Proteocephalus Weinland, 1858 (Cestoda: Proteocephalidae) parasites de Platydoras costatus (L.), poisson siluriforme du Paraguay
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19.
Els E. Martens 《Zoomorphology》1984,104(5):261-265
Summary A comparative ultrastructural study of the copulatory organ was carried out in four genera of Turbellaria-Monocelididae. In all four genera the male copulatory organ is of the conjuncta-duplex type and has a cirrus armed with spines. Fine-structural analysis of the cirrus spines reveals that these structures are specializations within the basement lamina of the cirrus. In this part of the male canal the basement lamina has a trilamellar structure. The spines are formed by a local thickening of the middle electron-dense layer and show a structural similarity in all the Monocelididae investigated.The systematic value of this character within the family Monocelididae is discussed.Abbreviations b bacteria - bl basement lamina - cr cell remnants - g granules of prostate glands - hd hemidesmosomes - l lumen of cirrus - m c muscles of cirrus - m b muscles of bulbus - mi mitochondria - p parenchymal elements - s spine - sp septum - st stylet - sz spermatozoa  相似文献   

20.
Redescripción de Proteocephalus paraguayensis (Rudin, 1917) (Cestoda: Proteocephalidae), parásito de Hydrodynastes gigas (Dum., Bibr. & Dum., 1854) de Paraguay. Se describe esta especie notable, considerada por Freze (1965) como species inquirenda. Si comparamos esta especie con otras especies de Proteocephalidea, veremos que ella presenta caracteres anatomo-morfológicos propios. Esta especie se caracteriza por: vitelógenos de posición dorsal, adosados a la musculatura interna longitudinal, desbordando en parte sobre el córtex y la médula; formación particular del útero; posición cortical del tronco uterino y medular de los divertículos uterinos; esfínter vaginal proximal; cirro muy alargado; glándula de Mehlis muy desarrollada. Consideramos P. paraguayensis como una especie válida y presumimos que el huesped-tipo es Hydrodynastes gigas (Dum., Bibr. & Dum., 1854). A pesar de las características que posee P. paraguayensis, pensamos que no es oportuno clasificar esta especie en un nuevo género monotípico. Proteocephalus paraguayensis, considered by Freze (1965) as a species inquirenda, is redescribed and figured. When compared with other members of the Proteocephalidea, the species shows the following morpho-anatomical characters: the vitelline follicles in a dorsal position, attached to the internal longitudinal musculature and extending into both the cortex and medulla; a characteristic formation of the uterus; the uterine stem in a cortical position and uterine branches in a medullary position; a proximal vaginal sphincter; a very elongate cirrus; and very large Mehlis' glands. The specific status of Proteocephalus paraguayensis is confirmed. Our specimens were taken from Hydrodynastes gigas (the host according to Rudin was Coluber sp.). Even though the species differs significantly from other proteocephalideans, its systematic and phylogenetic position is not yet clearly demonstrated, and it is decided to refrain from attributing it to a new genus.  相似文献   

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