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1

A new species of Acanthocotyle Monticelli, 1888 (Platyhelminthes: Monogenea: Acanthocotylidae) from the ventral skin of the banded stingaree, Urolophus cruciatus (Lacepede, 1804), from Tasmania, Australia

100%
Kearn G., Whittington I., Chisholm L., Evans-Gowing R.
Acta Parasitologica
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2016
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tom 61
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nr 3
2

Food and feeding habits of the blackspotted smooth-hound, Mustelus punctulatus (Elasmobranchii: Carcharhiniformes: Triakidae), from the northern Adriatic

100%
Lipej L., Mavric B., Resek S., Cherif M., Capape C.
Acta Ichthyologica et Piscatoria
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2011
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tom 41
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nr 3
Background. The blackspotted smooth-hound, Mustelus punctulatus Risso, 1826, has been regularly caught in the northern Adriatic Sea, although a decreasing trend in its catches was observed off the coast of Slovenia within the last decade. The knowledge of feeding behaviour of elasmobranch fish species, through understanding of the local food web structure, contributes to better and more efficient fish stock assessment and ecosystem modelling. This study is a first step in determining the prey consumption by the blackspotted smooth-hound in the area. Materials and methods. A total of 151 blackspotted smooth-hounds caught by commercial fishermen in the Gulf of Trieste from 4 June 2002 to 4 June 2003 were examined in this study. The stomach contents were removed, sorted and identified to the lowest possible taxon using identification keys. Preys were counted and weighed. Frequency of occurrence (F%), relative abundance (N%), the percentage by weight (W%), the Index of Relative Importance (IRI), and its standardized value (%IRI) were calculated following standard procedures. For comparing the diet between four different size classes we calculate average prey weight, dietary diversity, average meal, and trophic level for each size class. Results. Atotal of 130 fish stomachs contained prey items.Crustaceanswere themost important prey items (IRI%= 56.14), whereas cephalopods were the second mostly preyed animals (IRI% = 20.2). Teleost fish and bivalves were also found in the stomachs. The most important prey species was Solecurtus strigillatus. Larger sharks consumed larger preys. Male and female sharks consumed similar food. Juvenile individuals consumed predominantly crustaceans, while cephalopods were more important in the diet of adult individuals. The calculated trophic index (TROPH) of M. punctulatus from northern Adriatic Sea was 3.7, showing that it is a highly carnivorous species. Conclusion. This study is a first step in determining prey consumption by Mustelus punctulatus which is, despite the fact that is still common in the area, a rather poorly known species. For elucidating the role of benthic sharks in the study area the further step would be to study the diet of a closely related common smooth-hound M. mustelus.
3

Dendromonocotyle urogymni sp.nov. [Monogenea, Monocotylidae] from Urogymnus asperrimus [Elasmobranchii, Dasyatidae] off Eastern Australia

100%
Chisholm L., Whittington I.
Acta Parasitologica
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2009
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tom 54
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nr 2
113-118
Dendromonocotyle urogymni sp. nov. is described from the dorsal surface of the porcupine ray, Urogymnus asperrimus, kept at Cairns Marine Aquarium Fish in Cairns, Queensland, Australia. Dendromonocotyle urogymni can be distinguished most readily from the other 15 species in the genus by the male copulatory organ which has a distinct spherical inflation mid-way along its length. This is the first monocotylid to be described from U. asperrimus.
4
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Givetian (Middle Devonian) sharks from Cairo, New York (USA): Evidence of early cosmopolitanism

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Potvin-Leduc D., Cloutier R., Landing E., Hernick L. V., Mannolini F.
Acta Palaeontologica Polonica
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2015
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tom 60
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nr 1
Whereas cosmopolitan distribution patterns are established for many Late Devonian vertebrates (e.g., placoderms, onychodontiforms), few palaeobiogeographic studies have considered chondrichthyans. Recent discoveries of shark material demonstrate that some chondrichthyans were cosmopolitan by the Middle Devonian. Abundant Givetian microremains have been recovered from the Cairo quarry in eastern New York State, USA. These include teeth of two shark species with Gondwanan affinities, the omalodontid Portalodus mannoliniae sp. nov. and the antarctilamnid Wellerodus priscus. Abundant teeth of P. mannoliniae sp. nov. are characterized by a smooth diplodont crown, polarized cusps, and a labially oriented base. The teeth demonstrate monognathic heterodonty. The juvenile morph is distinguished from the adult by smaller size, slender cusps, and variation in the shape of the base. W. priscus is represented by rare juvenile teeth. Two groups of scales that show affinity to material from northern (Spain) and East Gondwana (Antarctica) are tentatively attributed to the two described species. Antarctilamnid distribution suggests a north Gondwanan origin and a colonization of the margin of the landmass before dispersing to Laurentia by the Middle Devonian. This material further indicates that vertebrate global dispersal was initiated by the Middle Devonian, and emphasizes earlier palaeogeographic interpretations that the Middle Devonian “Hamilton fauna” of North American Laurussia originated in the Early Devonian in South American Gondwana.
5
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Taxonomic notes on Phoebodus heslerorum and Symmorium reniforme [Chondrichthyes, Elasmobranchii]

100%
Ginter M.
Acta Palaeontologica Polonica
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2002
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tom 47
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nr 3
The revision of shark teeth from the Pennsylvanian black shales of central USA, ascribed to “Phoebodus heslerorum” Williams, 1985 and Symmorium reniforme Cope, 1893, shows that “Ph. heslerorum” is a junior synonym of “Cladodus” divergens Trautschold, 1879. This species belongs neither to Phoebodus nor to Cladodus, so a new genus Heslerodus is proposed. Very common, robust cladodont teeth with a deep labio−basal depression and two buttons, often referred to as S. reniforme, do not belong to the latter species, but to “Cladodus” occidentalis Leidy, 1859. The generic affinity of “C.” occidentalis is yet undetermined, but it is possible that it represents ctenacanthoids.
6
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A contribution to the knowledge of Miocene Elasmobranchii from Pinczow (Poland)

80%
Radwanski A.
Acta Palaeontologica Polonica
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1965
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tom 10
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nr 2
Of sever al remains of ela smobranch fishes, found in the Lower Tortonian Leitha-limestones at Pińczow, 6 forms are briefly described, so far either unknown from the territory of Poland, or insufficiently known. An attention is paid to the occurrence of the two species, characteristic of tropical seas: Hemipristis serra Ag. and Aetobatis arcuatus Ag.
7
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Biometric analysis of the teeth of fossil and Recent hexanchid sharks and its taxonomic implications

80%
Adnet S.
Acta Palaeontologica Polonica
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2006
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tom 51
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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.
8
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Chondrichthyan remains from the Lower Carboniferous of Muhua, Southern China

80%
Ginter M., Sun Y.
Acta Palaeontologica Polonica
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2007
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tom 52
|
nr 4
The shallow water assemblage of chondrichthyan microremains, teeth, tooth plates and scales, from the middle Tournaisian (Mississippian) of the vicinity of Muhua village, Guizhou province, southern China, is thus far the richest and most diverse association of this age collected from a single locality and horizon, and represents a chondrichthyan community very restricted in time and space. It was recovered from a small bioclastic limestone lens, MH−1, occurring among basinal marls near the base of the Muhua Formation, and dated as to the Siphonodella crenulata conodont Zone. The majority of the fauna presented here consists of teeth with euselachian−type bases and crushing crowns belonging to bottom−dwelling durophagous chondrichthyans, most probably feeding on shelly invertebrates such as the abundant brachiopods. We assigned most of these teeth to Euselachii (six species, among them Cassisodus margaritae gen. et sp. nov.), Petalodontiformes (two species), Holocephali (five species), and Euchondrocephali incertae sedis (Cristatodens sigmoidalis gen. et sp. nov.). We also identified primitive polycuspid, clutching teeth representing Phoebodontiformes (Thrinacodus bicuspidatus sp. nov.), Symmoriiformes, and Ctenacanthiformes. The scales are typical growing, compound forms of the protacrodont, ctenacanth, and hybodont types. Two problematic denticulated plates were found, one of which resembles mandibular or palatal plates of Sibyrhynchus (Iniopterygii). Several of the identified chondrichthyan taxa have hitherto been known only from Laurussia, especially from the British Isles and central USA. In particular we found the first record of Chondrenchelyssp. and Diclitodus denshumani outside their type locality. Th. bicuspidatus sp. nov., also known from Nevada, Iran, and NW Australia, appears to be a cosmopolitan, middle Tournaisian index fossil.
9

Redescription of Monocotyle myliobatis (Monogenea, Monocotylidae) from the type host Myliobatis aquila (Elasmobranchii, Myliobatidae) off the Algerian coast

80%
Tazerouti F., Neifar L., Euzel L.
Acta Parasitologica
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2011
|
tom 56
|
nr 3
Monocotyle was proposed by Taschenberg (1878) to accommodate M. myliobatis Taschenberg, 1878 from the gills of Myliobatis aquila (Linnaeus) caught at the Aquarium of the Zoological Station of Naples (Italy). There have been three descriptions of this species: the original one by Taschenberg (1878) and two which are incomplete by Perugia and Parona (1890) and Palombi (1942). Illustrations by these authors are poor and sometimes conflicting. We have rediscovered M. myliobatis on the gills of the type host Myliobatis aquila caught near Algiers, Tamentfoust (36°47′N, 3°12′E) (Algeria). We provide new illustrations of this monogenean, based on new specimens. We also redescribe the anatomy, with special attention to the male and female reproductive systems, and we provide additional data regarding the morphology, the number and arrangement of the septal sclerites of the haptor and the haptoral marginal papillae. We indicate the similarity between Monocotyle myliobatis and Monocotyle sp. Euzet et Maillard, 1967 collected from Pteromyleus bovinus, Geoffroy Saint Hillaire (Elasmobranchii, Myliobatidae) by J. Cadenat off Dakar (Senegal).
10

Trimusculotrema heronensis sp.nov. [Monogenea, Capsalidae] from the skin of the pink whipray Himantura fai [Elasmobranchii, Dasyatidae] from Heron Island, Queensland, Australia

80%
Whittington I. D., Kearn G. C.
Acta Parasitologica
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2008
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tom 53
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nr 3
Trimusculotrema heronensis sp. nov. is described from the skin of the pink whipray, Himantura fai, caught at Heron Island on the Great Barrier Reef, Queensland, Australia. The parasite differs from its closest relative, T. uarnaki, by its greater size and by features of the cirrus. There is evidence that the haptor of T. heronensis secretes cement. The living parasite is unable to swim. Whether Trimusculotrema spp. are benedeniines or entobdellines is discussed.
11

Scanning electron microscopy of the scolex and neck of the tapeworm Cathetocephalus thatcheri [Cestoda, Tetraphyllidea] from the sandbar shark Carcharhinus plumbeus [Chondrichthyes, Elasmobranchii]

80%
Conn D. B., Whittaker F. H., Curless W. W.
Acta Parasitologica
|
2004
|
tom 49
|
nr 1
Scanning electron microscopy of the scolex and neck of the cestode Cathetocephalus thatcheri confirmed earlier light-microscope descriptions showing that the scolex consists of a single apical lenticular adhesive complex, oriented transverse to the long axis of the strobila. The apical region of the scolex consists of a medial ridge from which extend numerous pairs of short bilamellate septa. On each side of the medial ridge, along its entire length, is a ridge in the form of sinusoidal wave that forms a loop around each of the septa. The tegument of the anterior surface of the medial ridge is formed into numerous tegumental folds that are aligned perpendicular to the long axis of the ridge. Posteriorly, the scolex has a rugose surface and forms a collar or lip around the upper part of the adherent surface. The sinusoidal ridges are continuous around the ends of the scolex. At the ends, the medial ridge tapers considerably. The tegument of the neck bears numerous papillae. No microtriches were observed on any part of the scolex or neck.
12
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Neoselachian remains [Chondrichthyes, Elasmobranchii] from the Middle Jurassic of SW Germany and NW Poland

80%
Kriwet J.
Acta Palaeontologica Polonica
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2003
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tom 48
|
nr 4
New neoselachian remains from the Middle Jurassic of SW Germany and NW Poland are described. The locality of Weilen unter den Rinnen in SW Germany yielded only few orectolobiform teeth from the Aalenian representing at least one new genus and species, Folipistrix digitulus, which is assigned to the orectolobiforms and two additional orectolobiform teeth of uncertain affinities. The tooth morphology of Folipistrix gen. nov. indicates a cutting dentition and suggests specialised feeding habits. Neoselachians from Bathonian and Callovian drill core samples from NW Poland produced numerous selachian remains. Most teeth are damaged and only the crown is preserved. Few identifiable teeth come from uppermost lower to lower middle Callovian samples. They include a new species, Synechodus prorogatus, and rare teeth attributed to Palaeobrachaelurussp., Pseudospinax? sp., Protospinax cf. annectans Woodward, 1919, two additional but unidentifiable Protospinax spp. and Squalogaleussp. Scyliorhinids are represented only by few isolated tooth crowns. No batoid remains have been recovered. The two assemblages contribute to the knowledge about early neoselachian distribution and diversity.
13

Critically endangered Pristis microdon [Elasmobranchii], as a host for the Indian parasitic copepod, Caligus furcisetifer Redkar, Rangnekar et Murti, 1949 [Siphonostomatoida]: New records from Northern Australia

71%
Morgan D. L., Tang D., Peverell S. C.
Acta Parasitologica
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2010
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tom 55
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nr 4
419-423
This paper presents the first records of the parasitic copepod Caligus furcisetifer Redkar, Rangnekar et Murti, 1949 beyond Indian waters, specifically, on the body surface and head of the critically endangered largetooth sawfish (commonly referred to as the freshwater sawfish in Australia), Pristis microdon Latham, 1794 (Elasmobranchii, Pristidae), in brackish tidal waters of the Fitzroy River in the Kimberley region of Western Australia and the Leichhardt River in the Gulf of Carpentaria in northern Queensland. This represents a geographic range extension of ∼8000 km for this parasite. Further, it is only the second member of the genus Caligus to be found on an elasmobranch host in Western Australia and it is the first time this species has been reported from the Southern Hemisphere. Male biased dispersal of P. microdon may be the vector in which the parasite has dispersed from India across to northern Australia, or vice versa. A decline in populations of the critically endangered P. microdon (and possibly other pristid species) in these regions may lead to a concomitant decline in their parasite fauna.
14
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Late Eocene scyliorhinid sharks from the Trans-Urals, Russia

71%
Malyshkina T.
Acta Palaeontologica Polonica
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2006
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tom 51
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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.
15

A new genus and new species of microbothriid monogenean [Platyhelminthes] with a functionally enigmatic reproductive system, parasitic on the skin and mouth lining of the largetooth sawfish, Pristis microdon, in Australia

61%
Kearn G. C., Whittington I. D., Evans-Gowing R.
Acta Parasitologica
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2010
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tom 55
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nr 2
115-122
Dermopristis paradoxus gen. et sp. nov., a microbothriid monogenean parasite from the skin and mouth lining of the largetooth sawfish, Pristis microdon (Elasmobranchii, Pristidae) in Australia, is described. The parasite has 2 juxtaposed testes and differs from other microbothriids in possessing a unique and unusual terminal male reproductive tract comprising a proximal and a distal tube, the latter with a conspicuous opening on the ventral surface and lacking a recognisable male copulatory organ. The smalltooth sawfish, P. pectinata, also has a skin-parasitic microbothriid, Dermophthirioides pristidis Cheung et Nigrelli, 1983, but this parasite species has a prominent copulatory papilla. Dermopristis paradoxus also has parallel ridges with broad tops running in a roughly transverse direction across the ventral surface of the body. The ventral ridges are prominent from the level of the pharynx to the posterior region of the body. The function of the ridges is unknown. Reproductive biology, attachment and feeding in D. paradoxus are discussed. In the absence of unmounted parasite specimens for sectioning, a mounted specimen of D. paradoxus was released from the slide and successfully processed to provide serial, stained, resin sections. This useful technique is recommended to provide anatomical information in situations where only specimens on slides are available for study.
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