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1.
A new species of Grillotia Guiart, 1927 was recovered from the spotted skate (Raja straeleni Poll) from the south coast of the Western Cape, South Africa. Grillotia sasciae n. sp. is described based on morphological and molecular data. This species most closely resembles species in the subgenus Grillotia (viz., Grillotia borealis Keeney and Campbell, 2001, Grillotia brayi Beveridge and Campbell, 2007, Grillotia dollfusi Carvajal, 1971, Grillotia erinaceus Dollfus, 1969, Grillotia musculara Hart, 1936 and Grillotia patagonica Menoret and Ivanov, 2012) in having four hooks per principal row and intercalary hook rows in the metabasal region of the tentacular armature, a band of hooks on the external tentacular surface, numerous proglottids, and the presence of an uterine pore, a hermaphroditic sac, and internal and external seminal vesicles. The molecular phylogenetic analysis of the partial 28S rDNA gene, confirms the morphological data as it also groups Grillotia sasciae n. sp. within the G. erinaceus species complex. Grillotia sasciae n. sp. is distinctive among all other valid species in the complex by having two enlarged, uncinate hooks in the basal armature, of a different shape and size from the remaining hooks 1(1′) in the metabasal armature. In addition, the retractor muscle of Grillotia sasciae n. sp. attaches at the posterior region of the tentacular bulb rather than the middle portion, continuing posteriorly as seen in most congeners (viz., G. erinaceus, G. borealis, G. brayi, G. musculara and G. pantagonica). The new species is the seventh species within the subgenus Grillotia and the first record of a species of Grillotia from southern African waters.  相似文献   

2.
Christianella Guiart, 1931 (Cestoda: Trypanorhyncha) is redefined as a subgenus of Grillotia Guiart, 1927 based on the type-species, G. (C.) minuta (van Beneden, 1849), from the elasmobranch Squatina squatina (Linnaeus). Grillotia smarisgora (Wagener, 1854) is treated as a synonym of G. (C.) minuta, as are G. angeli Dollfus, 1969 and G. bothridiopunctata Dollfus, 1969. Other species included in the subgenus are G. (C.) carvajalregorum Menoret & Ivanov, 2009 (formerly Progrillotia dollfusi Carvajal & Rego, 1983), G. (C.) australis Beveridge & Campbell, 2001, G. (C.) longispinis (Linton, 1890) n. comb. (formerly Rhynchobothrium longispine Linton, 1890) and G. (C.) yuniariae Palm, 2004. The subgenus is similar to Grillotia Guiart, 1927 (sensu stricto), having two bothria and an atypical heteroacanthous armature, but differs in having a single row of intercalary hooks, fewer, elongate segments with testes often in longitudinal columns, a distinctive basal armature, an internal seminal vesicle which extends beyond the cirrus or hermaphroditic sac and no uterine pore. The adults of three species are known, all parasitising members of Squatina Duméril.  相似文献   

3.
Non-native Spartina spp. have invaded many coastal saltmarshes worldwide. Introduced Spartina may cause problems like displacement of native vegetation and hybridisation with native species, leading to changes to relevant ecosystem services and saltmarsh geomorphology. Here we report the extensive and so far overlooked replacement of the native Spartina maritima by non-native S. anglica and S. townsendii along 400 km of the coast of the north-western Adriatic Sea (Mediterranean Sea). We analysed the distribution of both native and non-native Spartina spp. along the six main saltmarsh areas in the region, and produced maps of their presence by using a combination of genetic tools, morphological analysis and geotagged photographs, complemented with field observations. We also reviewed historical herbaria from the region to explore when the first non-native introductions could have occured. We found that S. anglica and S. townsendii are unexpectedly widespread, having established along the whole study region, in one lagoon totally replacing the local native species. Its introduction happened virtually unnoticed, and misidentified herbarium specimens date back as early as 1987. We discuss the ecological implications of this overlooked extensive replacement, and the need for a comprehensive assessment of the status of the saltmarshes in this region, both to protect the few remaining patches of the native S. maritima and control the spread of the non-native species across the Mediterranean Sea.  相似文献   

4.
The surface ultrastructure of two monotypic trypanorhynch genera is described based on new material of Grillotiella exilis (Linton, 1909) and type material of Pseudonybelinia odontacantha Dollfus 1966. In G. exilis, spiniform microtriches cover the bothrial surfaces and the anterior part of the pars vaginalis posterior to the bothria. Bifurcate microtriches adorn the bothrial margins, filiform microtriches the scolex peduncle, and capilliform microtriches the posterior scolex end. This microthrix pattern resembles that found in, e.g., Grillotia erinaceus (van Beneden, 1858), with the difference that the anterior part of the pars vaginalis is covered with a collar of multidigitate palmate microtriches. The position of Grillotiella within the Grillotiinae, Lacistorhynchidae is supported based on these data. The bothria and scolex peduncle of P. odontacantha are covered with acerosate and unciniform microtriches on the distal bothrial surface and capilliform microtriches on the scolex peduncle. Short filiform microtriches cover the appendix. The microthrix pattern resembles that of the Tentaculariidae but with unciniform and acerosate microtriches densely covering the entire distal bothrial surface. Tegumental grooves are present on the posterior bothrial margin. They can be distinguished from bothrial pits in otobothrioid trypanorhynchs in having similar unciniform microtriches compared to the other parts of the bothrial surface and in lacking any spiniform microtriches. With the absence of bothrial pits as characteristic for the otobothrioids and its characteristic microthrix pattern, P. odontacantha together with Paranybelinia otobothrioides Dollfus 1966, both belonging to the Paranybeliniidae change their position in the most recent system from the Otobothrioidea into the Tentacularioidea.  相似文献   

5.
Three oligo-raker species (?19 rakers on the first gill arch) of the genus Melamphaes out of the “M. typhlops” group are considered. The validity of M. indicus Ebeling is restored. This species inhabits equatorial and tropical waters of the Indian Ocean and the western part of the Pacific Ocean. M. eurous sp. n., which is related to M. indicus, is described from equatorial waters of the eastern part of the Pacific Ocean. M. typhlops (Lowe) inhabiting the northern part of the Atlantic Ocean, from the equatorial zone about to 45° N, is redescribed.  相似文献   

6.
Microsomacanthus diorchis (Fuhrmann, 1913) is redescribed and illustrated on the basis of the type-material and new findings from common eider Somateria mollissima captured in Iceland and specimens from the same host species from the Barents, White and Bering Seas. A lectotype is designated and an amended diagnosis is provided. The main differentiating features of M. diorchis are the size and shape of rostellar hooks and the cirrus, the well-marked delay in the antiporal testis development and the bow-shaped uterus. This parasite is shown to be specific to S. mollissima for both Atlantic and Pacific populations of the host. Hymenolepis (Microsomacanthus) somateriae of Bishop & Threlfall (1974) [nec M. somateriae Ryzhikov, 1965] is recognised as a synonym of M. diorchis (Fuhrmann, 1913). The taxonomic position of the species described as Aploparaksis murmanica Baylis, 1919 from common eider is discussed.  相似文献   

7.
The Indo-Pacific marine atherinid fishes Atherinomorus forskalii (Rüppell, 1838), Atherinomorus lacunosus (Forster, 1801), and Atherinomorus pinguis (Lacepède, 1803) are redescribed as valid species based on the types and non-type specimens collected throughout the Indo-Pacific. They are similar to each other chiefly in having a wide midlateral band (almost the same or greater than the midlateral scale width), large mouth (posterior tip of upper jaw reaching to or beyond a vertical through anterior margin of pupil), and no distinct tubercle at the posterior end of the dentary. All three species are distinguishable from congeners by those characters. The three species have long been confused with each other or synonymized erroneously as a single species. Atherinomorus forskalii, known from the Red Sea and eastern Mediterranean, differs from Atherinomorus lacunosus and Atherinomorus pinguis in having conspicuous, large endopterygoid teeth, forming obvious tooth ridges. Atherinomorus lacunosus, widely distributed in almost the entire Indo-Pacific, from East Africa to Tonga, north to southern Japan, and south to northern Australia, differs from Atherinomorus pinguis in having a wider midlateral band (the lower margin reaching to almost the center of the fourth scale row at level of the anal fin origin vs. the lower margin reaching to the ventral end of the third scale row in Atherinomorus pinguis) and more numerous midlateral scales (40–44 vs. 38–41 in Atherinomorus pinguis). Atherina morrisi Jordan and Starks, 1906, Hepsetia pinguis mineri Nichols and Roemhild, 1951, Pranesus capricornensis Woodland, 1961, Pranesus maculatus Taylor, 1964, and Pranesus pinguis ruppelli Smith, 1965, are regarded as junior synonyms of Atherinomorus lacunosus. Atherinomorus pinguis is also widely distributed in the Indo-West Pacific, from East Africa to northern Australia and north to southern Japan. Atherina pectoralis Valenciennes, 1835, is considered a junior synonym of Atherinomorus pinguis. Supplementary material to this paper is available in electronic format at  相似文献   

8.
The current status of Placostromella (Ascomycota, Dothideomycetes inc. sed.) is discussed, and a third species is added to the genus based on Palawaniella castanopsis J.N. Kapoor. Both species occur on living leaves of Castanopsis (Fagaceae) in South and East Asia. Placostromella castanopsis and the type P. macrospora are fully redescribed and illustrated.  相似文献   

9.
Salmon Salmo salar L. and brown trout S. trutta L. juveniles were examined for the presence of accidental monogenean ectoparasitic species of Gyrodactylus Nordmann, 1832 in the Baltic and White Sea basins of Russian Karelia in order to estimate the frequency of host-switching attempts on an ecological timescale. To collect phylogeographical information and for exact species identification, the parasites were characterised by nuclear internal transcribed spacer sequences of rDNA (ITS) and, for some species, also by their mitochondrial DNA (CO1 gene) sequences. Four accidental Gyrodactylus species were observed on salmon and brown trout. A few specimens of G. aphyae Malmberg, 1957, the normal host of which is the Eurasian minnow Phoxinus phoxinus (L.), were observed on lake salmon from the Rivers Kurzhma (Lake Kuito, White Sea basin) and Vidlitsa (Lake Ladoga, Baltic basin). G. lucii Kulakovskaya, 1952, a parasite of the northern pike Esox lucius L., was observed on salmon in the Kurzhma. In the River Vidlitsa, two specimens of G. papernai Ergens & Bychowsky, 1967, normally on stone loach Barbatula barbatula (L.), were found on salmon. On anadromous White Sea salmon in the River Pulonga in Chupa Bay, a few salmon parr carried small colonies of G. arcuatus Bychowsky, 1933, which were shown to have originated from the local three-spined stickleback Gasterosteus aculeatus L. consumed as prey. No specimens of Gyrodactylus salaris Malmberg, 1957 were observed, although the Pulonga is the nearest salmon spawning river to the River Keret', which is heavily infected with introduced G. salaris. In the River Satulinoja, Lake Ladoga, three specimens of G. lotae Gusev, 1953, from burbot Lota lota (L.), were collected from a single brown trout S. trutta. All nonspecific gyrodactylid infections on salmonids were judged to be temporary, because only a few specimens were observed on each of the small number of infected fishes. The prevalence of endemic G. salaris was also low, only 1% (Nfish = 296) in Lake Onega and 0.7% (Nfish = 255) in Lake Ladoga, while brown trout specific Gyrodactylus species were not observed on any of the 429 trout examined from the Ladoga basin. The host-specific and unspecific burden of Gyrodactylus spp. on these 'glacial relict' populations of salmon and brown trout was very low, suggesting a generalised resistance against the co-evolved freshwater parasite community, or some kind of 'vaccination' effect. These hypotheses deserve further testing.  相似文献   

10.
An extremely halophilic archaeon, previously named as Haloferax sp. strain Aa 2.2 or "Haloferax alicantei" that has been extensively used for genetic studies with halobacteria, was taxonomically characterized by using phenotypic tests (including morphological, physiological, biochemical and nutritional features), DNA-DNA hybridization and 16S rRNA sequence phylogenetic analysis. This organism was isolated in 1986 by Torreblanca et al. from a pond of a Spanish saltern located in Alicante. The cells were pleomorphic, Gram negative and grew optimally at 25% NaCl. The polar lipid composition was similar to that of species of the genus Haloferax. The DNA G+C content of this strain was 64.5 mol%. Phylogenetic analysis based on 16S rRNA sequence comparison confirmed that this archaeon is a member of the genus Haloferax and was most closely related to Haloferax volcanii. DNA-DNA hybridization between strain Aa 2.2 and the type strain of all named species of the genus Haloferax revealed low levels of relatedness (25-2%), supporting the placement of this organism in a new species. On the basis of the phenotypic characteristics, molecular data and phylogenetic analysis we propose to name strain Aa 2.2 as a new species, Haloferax lucentensis sp. nov. The type strain is Aa 2.2 (=JCM 9276=NCIMB 13854=CIP 107410=DSM 14919=CECT 5871=CCM 7023).  相似文献   

11.
12.
The onchobothriid tapeworm genus Megalonchos Baer & Euzet, 1962 is revised and the generic diagnosis amended based on the examination of some of Southwell's material of M. mandleyi (Southwell, 1927) Baer & Euzet, 1962, the type-specimens of M. dubius Prudhoe, 1969 and M. musteli Prudhoe, 1969, and material of two new species, M. sumansinghai n. sp. and M. shawae n. sp., collected from the snaggletooth shark Hemipristis elongatus off northern Australia. Based on their possession of two pairs of uni-pronged hooks (rather than one pair of bi-pronged hooks) and possession of, rather than lack of, post-vaginal testes, M. dubius and M. musteli are transferred to Biloculuncus Nasin, Caira & Euzet, 1997 as B. dubius (Prudhoe, 1969) n. comb. and B. musteli (Prudhoe, 1969) n. comb. Both new species of Megalonchos differ from M. mandleyi in their possession of conspicuously smaller hooks and shorter cephalic peduncles. The new species are readily distinguished from one another in that, whereas the pores of the axial prongs of the medial and lateral hooks are located well anterior to the middle of the prong in M. sumansinghai n. sp., they are well posterior to the middle of the prongs in M. shawae n. sp. In addition, the base of the lateral hook is longer relative to that of the medial hook in the latter species than it is in the former species. The proglottid anatomy of valid species of Megalonchos is described for the first time, and the lack of post-vaginal testes is confirmed for the genus. In addition, members of this genus appear to be characterised by a sacciform uterus that extends only to the level of the cirrus-sac and an ovary that is H-shaped in frontal view and bilobed in cross-section. Species of Megalonchos have now been reported from two of the eight known species of hemigaleid sharks.  相似文献   

13.
Protocotyle euzetmaillardi n. sp. is described from the gills of the sixgill shark Hexanchus nakamurai Teng caught in deep-sea off New Caledonia, South Pacific. The new species is compared with the two other species of the genus (both from the only other species in this shark genus, H. griseus (Bonn.)), namely P. grisea (Cerfontaine, 1899) Euzet &; Maillard, 1974, redescribed from vouchers, and P. taschenbergi (Maillard &; Oliver, 1966) Euzet &; Maillard, 1974, redescribed from its type-specimens. The anatomy of the reproductive system is detailed; all three species have a characteristic oötype with longitudinal cells (‘ootype côtelé’ of Euzet &; Maillard). The following unique combination of characters differentiates the new species from its two congeners: posterior lobe of seminal vesicle absent, diverticulum of oviduct present and small body size. Furthermore, its tubular ovary does not include a region with sperm, which is present in both of the other species, and its eggs have only one filament, whereas eggs in the uterus have one or two filaments in P. grisea and one filament in P. taschenbergi. The latter features differ from existing diagnoses of Protocotyle, in which eggs with two filaments and the presence of a tubular ovary dilated with sperm are key characteristics.  相似文献   

14.
A new genus is erected for Hysteropterum boreale Melichar, 1902 which is redescribed. Lectotype is designated in the type series of the species deposited in the Zoological Institute of the Russian Academy of Sciences (St. Petersburg, Russia). Photographs of the female (paralectotype) and drawings of the male (lectotype) genitalia are provided.  相似文献   

15.
Atactorhynchus duranguensisn. sp. (Acanthocephala: Atactorhynchinae) is described from the intestine of Cyprinodon meeki Miller, an endemic freshwater fish from a far-inland locality of Mexico. Diagnostic features include: body small, stout, ventrally curved; small cylindrical proboscis armed with 16 alternating vertical rows of four or five hooks; anterior two or three hooks conspicuous, stout and larger than other hooks, and have large, rod-shaped roots with a markedly and abruptly enlarged base; three posterior hooks of each row are smaller and rootless; single-walled proboscis receptacle; lemnisci equal in length, elongate and robust; and cement gland syncytial, larger than testis. The new species is smaller than A. verecundus Chandler, 1935, the only previously described species in the genus. The shape of the proboscis of the new species is strikingly different from that of A. verecundus, which is widest at the apex. Likewise, the greatest width of the trunk of the new species is in about the middle, differing from that of A. verecundus where the trunk is widest posteriorly. The new species also can be distinguished from A. verecundus because of its much smaller hook lengths and slightly smaller proboscis. In addition, the proportion of large apical proboscis hooks in relation to the small basal hooks is different: the basal hooks of A. verecundus are about half the size of the anterior hooks and but only about a quarter of the size in A. duranguensis. Unlike A. verecundus, the base of the roots are markedly and abruptly enlarged in the new species. Finally, the eggs of the new species are smaller (23–27 × 8–10 m) than those of A. verecundus (27–30 × 12–13 m).  相似文献   

16.
The genus Tournayellina (family Chernyshinellidae), important for stratigraphy of the Devonian–Carboniferous boundary interval, is revised. Species and generic morphological characters are considered and the species composition of the genus is revised. The evolution of the family is discussed and its geographical and stratigraphic distribution is examined. The species Tournayellina quadrilobata Postojalko, 1999 is redescribed in accordance with new data on its morphology. The new species T. intermedia Stepanova, sp. nov. is established.  相似文献   

17.
The temnospondylCheliderpeton vranyi Fritsch, 1877 from the Lower Permian Ruprechtice horizon (Rotliegend) of the Intrasudetic Basin (Bohemia, Czech Republic) is redescribed. Many features of the skeleton permit a new understanding of the type species and consequently of the genus. Diagnostic characters are the narrow and round-tipped snout, straight to convex outline of the skull roof, narrow and long otic notch, posteriorly expanded quadratojugal, and the relatively wide and short rhombic interclavicle. The ilium with a short, expanded dorsal branch and the missing contact of nasal/maxilla are features shared with the related Upper PermianIntasuchus from Russia and the Eryopidae.Actinodon germanicus is a junior synonym ofCheliderpeton vranyi.   相似文献   

18.
The gastropod Hexaplex trunculus is widely distributed in a relatively large range of habitats, but has no dispersal stage. We investigated its genetic structure across its distribution range, from Mediterranean Sea to adjacent Atlantic coasts, by sequencing mitochondrial DNA portions of the NADH dehydrogenase gene ND2 (420 pb) and the internal transcribed spacer ITS2 (450 pb). Our results suggested a significant genetic variability of ND2 (π = 0.009 and Hd = 0.629) and low variability of the ITS2 sequences. A strong phylogeographic break, separated the Aegean populations from those of Western/Eastern Mediterranean and the Atlantic ones, was founded. The tow lineages may have been separated by vicariance events due to the Peloponnese break that separates the Aegean populations from other populations and was maintained until now by the quasi-circular anticyclonic front associated to the straits of Cretan Arc of the Peloponnesian Peninsula. Tunisian coasts appear particularly diverse since the two divergent lineages co-occured. These results may have management consequences since H. trunculus is a high commercial value harvested species.  相似文献   

19.
Keys to 10 Palaearctic species of the dragonfly genus Aeschna are given. For adults of the two morphologically similar species Ae. juncea (Linnaeus, 1758) and Ae. subarctica Walker, 1908, new distinguishing characters are given. These are the shape of the genital plate and position of the anal appendages relative to the horizontal plane of the female body, and the shape of the processes of the anterior hooks of the male genitalia. Additionally, keys to the larvae based on characters of larvae reared in the laboratory are given. These keys allow species-level identification for early and middle larval instars.  相似文献   

20.
Pseudodiplectanum syrticum n. sp. (Monogenea: Diplectanidae) is described from the gills of Synapturichthys kleinii (Risso) collected from the Gulf of Gabès in the Mediterranean Sea off Tunisia. The new species differs from the congeneric species by the morphology of the penis and vagina. It resembles the Mediterranean species P. kearni Vala, Lopez-Roman & Boudaoud, 1980 from Solea vulgaris Quensel and P. gibsoni Oliver, 1987 from Michrochirus variegatus (Donovan) in its tubular penis, but it differs from these two species by having a vagina with a long tube presenting two loops and a male copulatory organ ending in a curved point. It also differs in the morphology and size of the transverse bars of the haptor. In P. syrticum the ventral transverse bar and dorso-lateral bars are longer than those of P. gibsoni (114 vs 69.5-89 microm and 48 vs 33-44 microm, respectively).  相似文献   

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