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1

A new onchoproteocephalidean cestode species from the spot-tail shark, Carcharhinus sorrah (Müller et Henle), in the Persian Gulf

100%
Ganjgah N. M., Haseli M.
Acta Parasitologica
|
2020
|
tom 65
|
nr 2
2

Lectin binding to olfactory system in a shark, Scyliorhinus canicula

88%
Franceschini V., Ciani F.
Folia Histochemica et Cytobiologica
|
1993
|
tom 31
|
nr 3
3
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Quantitative evaluation of shark fisheries from cantrang fishing gear in Mayangan Coastal Fishery Port, Probolinggo, Indonesia

75%
Permana R., Kusuma Pringgo D. N. Y. P.
World News of Natural Sciences
|
2020
|
tom 31
4

The lipoprotein crystals in yolk platelets of a shark, Squalus ocanthias [Selachii]

75%
Romek M., Kilarski W.
Folia Histochemica et Cytobiologica
|
1993
|
tom 31
|
nr 3
5
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Late Oligocene sharks and rays from the Chandler Bridge Formation, Dorchester County, South Carolina, USA

63%
Cicimurri D. J., Knight J. L.
Acta Palaeontologica Polonica
|
2009
|
tom 54
|
nr 4
A diverse vertebrate fauna, dominated by elasmobranch taxa, was collected from the upper Oligocene (Chattian) Chandler Bridge Formation in Summerville, Dorchester County, South Carolina. Nearly 3,500 teeth and dermal denticles are assigned to 29 species of sharks and rays, and our sample includes the oldest known occurrence of the whale shark, Rhincodon, as well as a new skate, Raja mccollumi sp. nov. The Chandler Bridge elasmobranch assemblage is comparable in species diversity to Chattian assemblages of Virginia and North Carolina, USA, and Germany. Notable absences from Germany include Rhincodon, Hemipristis, and Sphyrna zygaena, likely reflecting the influence of colder water on the North Sea Basin during the Chattian. Squaloids, pristiophoroids, and hexanchoids are known from Chattian deposits of the Albemarle Embayment (North Carolina), Salisbury Embayment (Virginia), and North Sea Basin, but these taxa are absent from the Chandler Bridge assemblage, perhaps because of shallow, warm water (20 to 25°C) conditions within the more southerly Charleston Embayment.
6

Endohelminth parasites of the leafscale gulper shark, Centrophorus squamosus (Bonnaterre, 1788) (Squaliformes:Centrophoridae) off Madeira Archipelago

63%
Costa G., Chada T., Melo-Moreira E., Cavallero S., D'Amelio S.
Acta Parasitologica
|
2014
|
tom 59
|
nr 2
The endohelminth parasite fauna of a deep water shark, the leafscale gulper shark, Centrophorus squamosus, examined from Madeiran waters, from September 2009 to January 2010, consisted of larval and juvenile cestodes of two orders, namely Trypanorhyncha and Tetraphyllidea, and L3 stages of Anisakis spp. Infection with Anisakis spp. could be due to the shark’s opportunistic feeding on squids and black-scabbard fish, Aphanopus carbo, which is heavily parasitized by Anisakis spp. in Madeira waters. The occurrence of larval and juvenile cestodes only, in this shark, suggests that the leafscale gulper shark features as a paratenic or a dead-end host for the parasites.
7
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Late Cretaceous sharks Cretoxyrhina and Cardabiodon from Montana, USA

63%
Siverson M., Lindgren J.
Acta Palaeontologica Polonica
|
2005
|
tom 50
|
nr 2
The middle part of the Cretaceous represents a time of high diversity and rapid rates of dental evolution in lamniform sharks. Several species had a very wide spatial distribution with recorded occurrences in both hemispheres. We have examined isolated teeth of Cretoxyrhina and Cardabiodon from eastern Russia, Mangyshlak in Kazakhstan, and the Western Interior of the USA. The material indicates that samples of isolated teeth of the two genera have high potential in intercontinental correlation of the upper Albian to mid−Turonian interval in mid−palaeolatitude deposits, poor in other age−diagnostic fossil groups. The utilization of these lamniforms in mid−Cretaceous biostratigraphy is currently hampered by the nearly total absence in the literature of well illustrated, well dated and sufficiently large samples of isolated teeth of the two genera. As a first step towards the establishment of an intercontinental elasmobranch zonation for mid−Cretaceous strata in temperate palaeo−regions, we describe and illustrate samples of teeth of Cardabiodon venator sp. nov. and Cretoxyrhina mantelli from the lower middle Turonian Collignoniceras woollgari regulare Zone in the Fairport Member of the Carlile Shale in east−central Montana, USA. These samples could serve as reference points for future biostratigraphic studies of Cretoxyrhina and Cardabiodon. The extinction of Cretoxyrhina may be diachronous, as regional last appearance data range from the upper Santonian (Marsupites testudinarius Zone) in Western Australia to the uppermost lower Campanian (informal Belemnellocamax mammillatus zone; a lateral equivalent to the German Gonioteuthis quadrata gracilis/Belemnitella mucronata Zone) in southern Sweden.
8

The antipromoting effect of alkyloglycerols from shark liver oil

63%
Miloszewska J., Krotkiewski M.
Cellular and Molecular Biology Letters
|
2002
|
tom 07
|
nr 2
9

Pancreatonema americanum sp.nov. [Nematoda, Rhabdochonidae] from the pancreatic duct of the dogfish shark, Squalus acanthias, from the coast of Massachusetts, USA

63%
Moravec F., Borucinska J. D., Frasca S.
Acta Parasitologica
|
2001
|
tom 46
|
nr 4
10
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Deep water chondrichthyans from the Early Miocene of the Vienna Basin (Central Paratethys, Slovakia)

51%
Underwood C. J., Schlogl J.
Acta Palaeontologica Polonica
|
2013
|
tom 58
|
nr 3
Sampling of latest Burdigalian (Miocene) silty clays from the Malé Karpaty Mountains in the Slovakia revealed a deep−water, low diversity shark fauna. The fauna is dominated by teeth of very small squaliform sharks, including two new species, Eosqualiolus skrovinai sp. nov. and Paraetmopterus horvathi sp. nov. The generic composition of the squaliform fauna is more similar to that known from the Eocene than that of today, suggesting a post–early Miocene faunal turnover within this clade, at least locally. Nectobenthic, non squaliform sharks are rare, but include the new sawshark species Pristiophorus striatus sp. nov., while minute teeth of an enigmatic taxon described here as Nanocetorhinus tuberculatus gen. et sp. nov. probably indicate the presence of a previously unrecorded planktivore. The unusual composition of the fauna, with the complete absence of taxa known to be of medium to large size, suggests an unusual, and probably very stressed, palaeoenvironment.
11
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Biometric analysis of the teeth of fossil and Recent hexanchid sharks and its taxonomic implications

51%
Adnet S.
Acta Palaeontologica Polonica
|
2006
|
tom 51
|
nr 3
A biometric analysis of the lower teeth of Recent cow sharks (Hexanchidae) investigates the ontogenetic and phylogenetic aspects of the dental characters employed by many ichthyologists and palaeontologists. The dental characters currently used to separate two extant species of sixgill sharks (Hexanchus griseus and H. nakamurai) are analysed and the fossil record of their relatives reviewed. The main results suggest that the cusp number ratio (number of cusps per mm) is preferable to width of the lower tooth for inference of total body size, at least in species of Hexanchus. The presence of a serrated edge or an enlarged acrocone appears to depend on ontogeny and care must be taken when using these as taxomomic characters. Three Eocene species of Hexanchus, H. collinsonae, H. hookeri, and H. agassizi, and a new assemblage of fossil teeth from the late Ypresian/early Lutetian (Early/Middle Eocene) of south−western France, are also analysed. The first two of these species may be ontogenetic states of H. agassizi. Hexanchus agassizi, belonging to the vituliform lineage and closely related to the living H. nakamurai, is considered here to be the only species of Hexanchus in the Lower to Middle Eocene. A brief overview of Palaeogene Hexanchus, suggests no evidence of the grisiform group (closely related to living H. griseus) before the Late Eocene.
12

New host and ocean records for Driocephalus cerebrinoxius (Sphyriidae, Siphonostomatoida) and a reconsideration of phylogeny within Sphyriidae

51%
Benz G. W., Nagasawa K., Yamaguchi A., McMeans B. C., McElwain A.
Acta Ichthyologica et Piscatoria
|
2006
|
tom 36
|
nr 1
Background. Driocephalus cerebrinoxius is an unusual representative of an unusual family of parasitic copepods (Sphyriidae, Siphonostomatoida, Copepoda). This report documents new host and ocean records for D. cerebrinoxius and considers the phylogenetic relationships amongst sphyriid (Sphyriidae) genera.Materials and Methods. Copepods collected from trawl-caught fishes were studied using light microscopy and standard staining, manipulation, and measuring techniques. The phylogenetic analysis (parsimony outgroup analysis) was conducted using adult female morphological characteristics of sphyriid genera. Results. Driocephalus cerebrinoxius is reported for the first time from the Pacific Ocean and from the star-spotted smooth hound, Mustelus manazo (Triakidae, Carcharhiniformes). The cladistic analysis of sphyriid taxa resulted in 12 shortest trees, each with a length of 16 and consistency index of 0.875. Strict and majority rule consensus trees are presented. Conclusion. Due to the paucity of morphological characters available for analysis, a robust phylogenetic hypothesis for taxa comprising Sphyriidae is best sought using molecular tools. Without a robust phylogeny it is premature to undertake associated analyses regarding historical ecology within Sphyriidae.
13

Helminth parasites of the Atlantic chub mackerel, Scomber colias Gmelin, 1789 from Canary Islands, Central North Atlantic, with comments on their relations with other Atlantic regions

51%
Costa G., Cavallero S., D’Amelio S., Paggi L., Santamaria M. T. G., Perera C. B., Santos M. J., Khadem M.
Acta Parasitologica
|
2011
|
tom 56
|
nr 1
Eleven parasite taxa were found infecting 68 Atlantic chub mackerel, Scomber colias Gmelin, 1789 from the Canary Islands, Central North Atlantic. The most abundant parasites were the gill monogenean Pseudokuhnia minor (P = 54.4%), larval anisakid nematodes (P = 11.8%) in the body cavity, a larval tetraphyllidean infecting bile ducts (P = 8.8%) and didymozoid digeneans infecting the gills (P = 7.4%). No correlation between fish length and abundance of infection with these parasites was found. Within the Atlantic, the comparison of present results with previous reports on the occurrence of parasites in this fish host, might suggest that there is more than one population unit of Atlantic chub mackerel in the Eastern Atlantic.
14
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Morphology and histology of dorsal spines of the xenacanthid shark Orthacanthus platypternus from the Lower Permian of Texas, USA: palaeobiological and palaeoenvironmental implications

51%
Beck K. G., Soler-Gijon R., Carlucci J. R., Willis R. E.
Acta Palaeontologica Polonica
|
2016
|
tom 61
|
nr 1
Detailed studies on Carboniferous species of the xenacanth Orthacanthus have shown that the xenacanth dorsal fin spine can be used for skeletochronological analyses and provides valuable information about development, growth and environmental life conditions of those extinct sharks. We report here for the first time the histology and skeletochronology of Permian specimens, dorsal spines of Orthacanthus platypternus from the Craddock Bone Bed (lower Clear Fork Formation; Early Permian, Leonardian age) of northern Baylor County (north-central Texas, USA). Twelve dorsal spines of O. platypternus preserve a highly vascularized wall mainly composed of centrifugally growing dentine in a succession of dentine layers, probably deposited with an annual periodicity. As expected, spines of individuals with 1–2 dentine layers, presumably juveniles, present the smallest sizes. However, spines of individuals showing at least 3–4 dentine layers and interpreted to be subadults/young adults, are distributed in two spine-size clusters corresponding to females (probably the largest spines) and males, in agreement with the hypothesis of sexual size dimorphism proposed in a previous biometric analysis. Our comparative study of O. platypternus and the Stephanian species O. meridionalis further suggests that spine denticulation can be useful for distinguishing between species of Orthacanthus and sexually dimorphic forms (juvenile to adults) in each species. Total body length estimations of O. platypternus from the Craddock Bone Bed point to relatively large juveniles and small subadults/young adults (less than 2 m in total length), living as opportunistic predators in the pond-channel coastal plain environments represented by the bone bed deposits. The comparative analyses of the ontogenetic stages of the recorded specimens of O. platypternus and their distribution along different facies and localities indicate that this species was euryhaline, diadromous with a catadromous life-cycle which was strongly regulated by the semi-arid, seasonally dry tropical climate affecting western Pangaea during the Early Permian.
15

Some biological features of Pacific sleeper shark, Somniosus pacificus [Bigelow et Schroeder 1944] [Squalidae] in the Northwestern Pacific Ocean

51%
Orlov A. M., Moiseev S. I.
Oceanological Studies
|
1999
|
tom 28
|
nr 1-2
16

Distribution patterns and interactions of cestodes in the spiral intestine of the narrownose smooth-hound shark, Mustelus schmitti Springer, 1939 [Chondrichthyes, Carcharhiniformes]

51%
Alarcos A. J., Ivanov V. A., Sardella N. H.
Acta Parasitologica
|
2006
|
tom 51
|
nr 2
The distribution patterns and the cestode species interactions within the spiral intestine of 20 specimens of Mustelus schmitti from coastal waters off Mar del Plata, Argentina were studied. Six cestode species were found: Tetraphyllideans Calliobothrium barbarae, C. australis, C. lunae and Orygmatobothrium schmittii, diphyllidean Echinobothrium notoguidoi and trypanorhynch Eutetrarhynchus vooremi. The most common number of parasite species per host was 3. Brillouin’s diversity index ranged from 0.1 to 1.2 Berger-Parker dominance index indicated that C. barbarae was the dominant species, followed by O. schmittii and C. australis. Calliobothrium barbarae, C. australis and O. schmittii presented a broad distribution along the spiral intestine, whereas C. lunae, E. notoguidoi and E. vooremi showed a more restricted niche breadth. In general, the Renkonen’s index showed no evidence of niche overlap in the range of distribution of the different species. In most of the infracommunities, intraspecific aggregation was stronger than interspecific aggregation, indicating that competition may play a little role. The distribution patterns of the Calliobothrium specimens concurs with the predictions of attachment sites for Calliobothrium species made by previous authors.
17

Carotenoids in fillets of spiny dogfish shark - Squalus acanthias L. [Chondrichthyes: Squalidae]

51%
Czeczuga B., Czeczuga-Semeniuk E.
Bulletin of the Sea Fisheries Institute
|
1999
|
nr 2
18
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A new Pliensbachian [Early Jurassic] neoselachian shark fauna from Southern Sweden

51%
Rees J.
Acta Palaeontologica Polonica
|
2000
|
tom 45
|
nr 4
Hettangian to Pliensbachian neoselachian tooth assemblages from marine deposits in northwest Europe are dominated by palaeospinacids. In the Toarcian, elasmobranch faunas tend to be more diverse and several other neoselachian groups have their first occurrence. A small, but surprisingly diverse, neoselachian tooth assemblage, comprising seven taxa, has been extracted from Pliensbachian sediments within the Rya Formation in southern Sweden. The fauna includes five synechodontiform species; Synechodus occultidens, S. enniskilleni, 'Synechodus' sp., Paraorthacodus sp., and Sphenodus sp. The remaining two species include Hexanchidae indet. and Agaleus dorsetensis. The exclusively Early Jurassic A. dorsetensis is separated from all other neoselachians on the basis of tooth morphology and is here included in the new, monotypic family Agaleidae nov. The assemblage from the Rya Formation is the first selachian fauna to be recorded from the Jurassic of Sweden and it has a composition quite different from contemporary faunas found in other areas of Europe. The neoselachian part of the fauna is more diverse while hybodont sharks are represented solely by a single species.
19
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Late Eocene scyliorhinid sharks from the Trans-Urals, Russia

45%
Malyshkina T.
Acta Palaeontologica Polonica
|
2006
|
tom 51
|
nr 3
Priabonian deposits from two localities, Kurgan and Derney, in the Trans−Urals (Western Siberia) have yielded numerous selachian teeth. The carcharhiniform family Scyliorhinidae is represented by three species, including two new: Premontreia uralica sp. nov., Foumtizia zhelezkoi sp. nov., and F. pattersoni (Cappetta, 1976). Both genera are recorded from the West−Siberian Basin for the first time. Presumably all three species (including the one morphologically mimicking F. pattersoni, a species recorded from Ypresian of England) are endemic for the Trans−Urals region (contrary to the cosmopolitan lamniforms recorded previously from the area. The known distribution pattern of extant scyliorhinids supports the probability of endemism of the cat sharks from the West−Siberian Basin, which has also been isolated geographically from the Peri−Tethys during the Late Eocene marine regression. The peculiar local environmental conditions due to the Priabonian climatic cooling in the Boreal realm might have also facilitated the speciation.
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