Pandarus Leach, 1816 (Copepoda: Siphonostomatoida: Pandaridae) species collected from elasmobranchs off South Africa with the description of Pandarus echinifer n. sp.

Eight species of Pandarus Leach, 1816 collected from hosts caught off South Africa are reported. These species include P. bicolor Leach, 1816, P. niger Kirtisinghe, 1950 and P. carcharhini Ho, 1963 belonging to the "bicolor" group and P. cranchii Leach, 1819, P. satyrus Dana, 1849, P. smithii Rathbun, 1886 and P. sinuatus Say, 1818 belonging to the "cranchii" group. Notes on previous and new distinguishing features are provided with illustrations, specifically the relative lengths of the dorsal plates and caudal rami as well as the structure of the distomedial spine on the second segment of leg 1 exopod. Additionally, illustrated re-descriptions are provided for P. satyrus and P. sinuatus. Furthermore, a new species Pandarus echinifer n. sp., also belonging to the "cranchii" group, collected from the snaggletooth shark Hemipristis elongata (Klunzinger) is described. This species is most similar to P. sinuatus but can be distinguished from it by the heavily spinulated distomedial spine on the last segment of the first leg exopod. Molecular analysis of the cytochrome oxidase I partial gene is used to calculate sequence divergences amongst different individuals and species. According to the results (as well as based on morphological characters) P. rhincodonicus Norman, Newbound & Knott, 2000 is a synonym of P. cranchii. New hosts and geographic localities from South Africa (and Ningaloo Park, Western Australia) are reported.

New monogeneans from the bathydemersal southern African endemic catshark, Holohalaelurus regani (Gilchrist, 1922).

The catshark genus Holohalaelurus Fowler is currently represented by five species distributed off the southern and eastern parts of the African coast. Very few parasitological records exist for any of these five species, representing a significant knowledge gap. We report the first monogenean species from the bathydemersal species Holohalaelurus regani (Gilchrist): a new species of Microbothriidae Price, 1936, Leptomicrobothrium holohalaelure n. sp. from the dorsal skin surface, and a new species of Hexabothriidae Price, 1942 representing a new genus, Scyliorhinocotyle narvaezae n. gen., n. sp., from the gill lamellae. Both monogenean records represent the first for any member of the catshark genus Holohalaelurus. Previously we focused on the identification of monogenean taxa of emerging veterinary importance for public aquaria. We now begin a focused effort to document a generally unexplored monogenean biodiversity from diverse marine habitats off South Africa.

Sea lice (Copepoda: Caligidae) from South Africa, with descriptions of two new species of Caligus.

Thirteen species of sea lice (family Caligidae) are reported from a range of elasmobranch and actinopterygian fishes caught off South Africa or obtained from public aquaria in South Africa. Two new species of Caligus Müller, 1785 are described: C. linearis n. sp. from Pomatomus saltatrix (Linnaeus) and C. tumulus n. sp. from Chrysoblephus cristiceps (Valenciennes). A supplementary description is provided for both sexes of Caligus tetrodontis Barnard, 1948 taken from Amblyrhynchotes honckenii (Bloch) and previous records of this parasite from South African fishes are critically reviewed. It is concluded that Caligus material from Arothron hispidus Linnaeus was previously misidentified as C. tetrodontis and is in urgent need of re-examination. Morphological and molecular observations on Caligus furcisetifer Redkar, Rangnekar & Murti, 1949 indicate that this copepod is phenotypically and genetically identical to Lepeophtheirus natalensis Kensley & Grindley, 1973, and the latter becomes a junior subjective synonym of C. furcisetifer. We include new geographical distribution records for Caligus longipedis Bassett-Smith, 1898, C. rufimaculatus Wilson, 1905 and Lepeophtheirus spinifer Kirtisinghe, 1937, extending into South African waters, as well as both new distribution and host records for Alebion gracilis Wilson, 1905, Caligus dakari van Beneden, 1892 and Lepeophtheirus acutus Heegaard, 1943. The molecular analysis confirmed the monophyly of the genus Caligus. The South African species of Caligus did not cluster together, but the two included South African species of Lepeophtheirus were recovered as sister taxa.

A redescription of the female of Lernaeopoda bivia Leigh-Sharpe, 1930 (Lernaeopodidae: Siphonostomatoida) and a first description of the male.

Within the family Lernaeopodidae Milne Edwards, 1840 the females of Lernaeopoda spp. are very similar to those of Neoalbionella spp. Contrarily, the male morphology is different enough to allow distinction between species of the two genera. Unfortunately, males are not always attached to collected females and therefore often not described. Hence the validity of some of the Lernaeopoda spp. are still questionable due to incomplete descriptions of the female and no description of the male. Lernaeopoda bivia Leigh-Sharpe, 1930 is an example of an accepted species due to a redescription of the female done in 1986 but without a description of the male. Lernaeopoda bivia has only been reported twice, collected from Schroederichthys bivius (Müller & Henle). Recently, females with attached males were collected from Triakis semifaciata Girard from Inner Cabrillo Beach in southern California. The female morphology of L. bivia is similar to the previous redescription with some additional features and illustrations while the male conforms to the morphology of males of Lernaeopoda spp. The dental formula of males and females of the species of the genus differ with males having one P1, S1 less than females. The structure and armature of the appendages of the three described species of males (L. galei Krøyer, 1837, L. bidiscalis Kane, 1892 and L. bivia) is mostly similar with the tympanal membrane of the three species the most distinctive feature. A key to identify the females of the valid species of Lernaeopoda is provided.

Acanthocephalans from Australian elasmobranchs (Chondrichthyes) with a description of a new species in the genus Gorgorhynchus Chandler, 1934 (Rhadinorhynchidae).

Gorgorhynchus occultus n. sp. is described from Sutorectus tentaculatus (Peters) (Orectolobidae) collected off Bunbury, Western Australia in 1986. The new species differs from all other species of Gorgorhynchus Chandler, 1934 by having a suite of characters including a proboscis hook formula of 18-20 rows of 8-9 hooks, a well-developed neck, irregular circles of small spines in a single anterior field, the male reproductive system limited to the posterior quarter of the trunk and three cement glands. In a survey of 284 sharks collected between 2015 and 2018 from 10 localities in Australian waters, 11 individuals were infected with acanthocephalan cystacanths. One individual of Sphyrna mokarran (Rupell) (Sphyrnidae) was infected with Corynosoma cetaceum Johnston & Best, 1931. Serrasentis sagittifer (Linton, 1889) (Rhadinorhynchidae) was found in five individuals of S. mokarran, four individuals of Syphyrna lewini (Griffith & Smith) and one individual of Carcharhinus coatesi (Whitley) (Carcharhinidae). These infections may be accidental because it has been suggested that acanthocephalans cannot tolerate the high levels of urea used by marine and esturine elasmobranchs for osmoregulation. The two most common host species examined, S. mokarran and S. lewini had the highest intensities and prevalences of infection with S. sagittifer. Although more individuals of S. lewini were examined, S. mokarran had the higher prevalence of infection.

A new species of Branchellion Savigny, 1822 (Hirudinida: Piscicolidae), a marine leech parasitic on the giant electric ray Narcine entemedor Jordan & Starks (Batoidea: Narcinidae) off Oaxaca, Mexico.

Branchellion spindolaorum n. sp. (Hirudinida: Piscicolidae) is described based on specimens found parasitising the giant electric ray Narcine entemedor Jordan & Starks off the coast of Oaxaca, Mexico. The new species can be clearly distinguished from the other species of Branchellion Savigny, 1822 by the presence of 30 pairs of lateral branchiae and 10 pairs of pulsatile vesicles. The definition of the genus Branchellion is expanded to include species with either 30, 31 or 33 pairs of foliaceous (plate-like) lateral branchiae in the urosome. In addition, we provide for the first time for the genus, scanning electron micrographs of the secondary suckers located on the ventral surface of the posterior sucker. Additionally, partial DNA sequences of the mitochondrial cytochrome c oxidase subunit 1 (cox1) were generated and compared with homologous sequences of other species of the genus. Branchellion spindolaorum n. sp. represents the fourth species of the genus known in the Eastern Pacific and the first record of a leech parasitising N. entemedor.

A new species of Dollfusiella Campbell & Beveridge, 1994 (Cestoda: Eutetrarhynchidae), with remarks on Halysiorhynchus macrocephalus (Shipley & Hornell, 1906) (Cestoda: Mixodigmatidae) from the bowmouth guitarfish Rhina ancylostoma Bloch & Schneider (Rhinidae) in the Persian Gulf.

Dollfusiella nimai n. sp. (Cestoda: Eutetrarhynchidae) is described from the intestine of Rhina ancylostoma Bloch & Schneider in the Persian Gulf. The number of the hooks per half spiral row in the metabasal tentacular armature distinguishes the new species from its congeners, except for D. vooremi (São Clemente & Gomes, 1989) possessing approximately the same number of hooks per half spiral row. While the principle hooks 1(1')-21(21') were homeomorphous in the metabasal armature of D. nimai n. sp., the billhooks on the antibothrial surface and the uncinate hooks on the bothrial surface were the principle hooks 1(1')-16(16') in the metabasal armature of D. vooremi. Dollfusiella nimai n. sp. most closely resembles D. michiae (Southwell, 1929) in the tentacular armature as well as the morphology of the scolex and strobila but differs clearly in the number of the hooks per half spiral row in the metabasal tentacular armature (25-26 vs 16 respectively). A detailed examination of the specimens of Halysiorhynchus macrocephalus (Shipley & Hornell, 1906) (Cestoda: Mixodigmatidae) ex R. ancylostoma from the Persian Gulf revealed intraspecific variability including the number of the principle hooks per half spiral row in the metabasal armature, the number of the hook rows in the basal armature, and the size of the basal hooks.

Morphological variability and molecular characterization of Mawsonascaris australis (Johnston & Mawson, 1943) (Nematoda: Ascaridoidea: Acanthocheilidae) from the brown guitarfish Rhinobatos schlegelii Müller & Henle (Rhinopristiformes: Rhinobatidae).

A rare ascaridoid species, Mawsonascaris australis (Johnston & Mawson, 1943), is reported from the Taiwan Strait for the first time, and the brown guitarfish Rhinobatos schlegelii Müller & Henle (Rhinopristiformes: Rhinobatidae) represents a new fish host. The detailed morphology of M. australis was studied using light and scanning electron microscopy (SEM) based on the newly collected specimens. The results revealed some important, but previously unreported or erroneous, morphological features, including the lateral alae starting well posterior to the base of the ventrolateral lips, the presence of one pair of double paracloacal papillae and a single, small precloacal median papilla on the anterior margin of the cloaca. In addition, in order to determine whether the morphometric difference in the relative lengths of the right and left spicules represents intraspecific or interspecific variation, specimens of M. australis were characterized using molecular approaches by sequencing and analysing the ribosomal internal transcribed spacer (ITS) and mitochondrial cox1 genes. The results indicate that this morphometric difference represents intraspecific variability.

Tetraphyllidean and onchoproteocephalidean cestodes of elasmobranchs from Moreton Bay, Australia: description of two new species and new records for seven described species.

Parasitological examination of elasmobranchs of Moreton Bay, Queensland, Australia, resulted in the discovery of cestodes belonging to several armed genera of the Tetraphyllidea and Onchoproteocephalidea. Two new tetraphyllideans, Yorkeria moretonensis n. sp. and Yorkeria williamsi n. sp., are described from Chiloscyllium cf. punctatum (Hemiscylliidae). Yorkeria moretonensis n. sp. differs from its congeners in the possession of vitelline follicles that are discontinuous in the region of the ovary and in the length of its pedicels. Yorkeria williamsi n. sp. is most similar to Y. parva Southwell, 1927, but has larger, oval bothridia, longer pedicels and differences in the sizes of the scolex hooks. Yorkeria longstaffae Caira, Jensen & Rajan, 2007 is reported from Moreton Bay for the first time, and Spiniloculus mavensis Southwell, 1925 is re-reported from the type-locality and likely type-host (Moreton Bay and Chiloscyllium cf. punctatum, respectively), over 90 years after its original description. Six known onchoproteocephalideans, Acanthobothrium cannoni Campbell & Beveridge, 2002, A. chisholmae Campbell & Beveridge, 2002, A. ocallaghani Campbell & Beveridge, 2002, A. margieae Fyler, 2011, Megalonchos shawae Caira, Reyda & Mega, 2007 and M. sumansinghai Caira, Reyda & Mega, 2007, are reported from Moreton Bay for the first time, representing significant range extensions for all species.

Phylogenetic evidence for an ancestral coevolution between a major clade of coccidian parasites and elasmobranch hosts.

Cartilaginous fishes are the oldest jawed vertebrates and are also reported to be the hosts of some of the most basal lineages of Cestoda and Aporocotylidae (Digenea) parasites. Recently a phylogenetic analysis of the coccidia (Apicomplexa) infecting marine vertebrates revealed that the lesser spotted dogfish harbours parasite lineages basal to Eimeria Schneider, 1875 and the group formed by Schellackia Reichenow, 1919, Lankesterella Ames, 1923, Caryospora Leger, 1904 and Isospora Schneider, 1881. In the present study we have found additional lineages of coccidian parasites infecting the cownose ray Rhinoptera bonasus Mitchill and the blue shark Prionace glauca Linnaeus. These lineages were also found as basal to species from the genera Lankesterella, Schellackia, Caryospora and Isospora infecting higher vertebrates. These results confirm previous phylogenetic assessments and suggest that these parasitic lineages first evolved in basal vertebrate hosts (i.e. Chondrichthyes), and that the more derived lineages infect higher vertebrates (e.g. birds and mammals) conforming to the evolution of their hosts. We hypothesise that elasmobranchs might host further ancestral parasite lineages harbouring unknown links of parasite evolution.

Resurrection of Alebion difficile (van Beneden, 1892) (Copepoda: Siphonostomatoida: Caligidae) with notes on other species of Alebion Krøyer, 1863 collected from elasmobranchs off South Africa and an updated key of the adult females.

Alebion Krøyer, 1863 is one of the genera of the Caligidae Burmeister, 1835 and can easily be distinguished from other genera by the presence of modified exopodal spines on legs 1-3. Currently there are eight recognised species infecting a variety of elasmobranch hosts. Alebion difficile (van Beneden, 1892) is resurrected based on the difference in the structure of the spermatophores on the genital complex of the female but also the difference in the relative lengths of the posterior processes of the genital complex, the lateral processes on the first abdominal somite and the caudal rami. Additionally, the adult male of A. difficile is described and illustrated and notes provided about the morphology of the sub-adult females and males. Other Alebion species and their hosts collected off South Africa are reported and an updated key to the adult females of the species of Alebion is provided.

Description of four new species and a revision of the genus Tripaphylus Richiardi in Anonymous, 1878 (Copepoda: Siphonostomatoida: Sphyriidae).

Tripaphylus Richiardi in Anonymous, 1878 is one of the genera of the Sphyriidae Wilson, 1919 and it currently accommodates ten species. Only scanty descriptions are available for the females and some males of the species. Tripaphylus specimens, described and illustrated in this paper, were collected from elasmobranch hosts off the South African coast or came from the private collection of the late Dr G. Benz. Collected specimens were fixed and preserved in 70% ethanol, examined by light - and scanning electron microscopy, and compared with the known species. Descriptions and illustrations are provided for the transformed adult females and males of T. elongatus (Wilson, 1932) and T. versicolor (Wilson, 1919) while illustrated descriptions of the transformed adult females are also provided for T. ferox (Wilson, 1919) and T. vaissierei (Delamare Deboutteville & Nuñes-Ruivo, 1954). Additionally, the material previously reported as T. ferox is considered to represent T. elongatus and that reported as T. lobatus (Kirtisinghe, 1964) is considered a junior synonym of T. vaissierei. Based on the collected material the transformed adult female and male of T. lewisi n. sp. are described as well as the adult transformed females of T. benzi n. sp., T. hoi n. sp., and T. beatricae n. sp. A summarised review of the main features is provided for each of the previously described T. musteli (van Beneden, 1851), T. hemigalei Kirtisinghe, 1964, T. australis (Kabata, 1993), T. triakis (Castro Romero, 2001) and T. asymboli (Turner, Kyne & Bennett, 2003). Furthermore, reasons are provided for the recommendation that T. hemigalei be considered a species inquirenda. An identification key to the transformed adult females of all species of Tripaphylus is provided and the host records are also updated.

Redescription of Tripaphylus musteli (van Beneden, 1851) (Copepoda: Sphyriidae) and the relegation of Paeon Wilson, 1919 to synonymy with Tripaphylus Richiardi in Anonymous, 1878.

Tripaphylus musteli (van Beneden, 1851) (Copepoda, Siphonostomatoida, Sphyriidae) is redescribed from an adult female collected from the branchial chamber of a starry smooth-hound, Mustelus asterias Cloquet (Carcharhiniformes, Triakidae), captured in the English Channel off Portland, UK. The new account of T. musteli is the first based on a complete adult female and highlighted the lack of a robust distinction separating Tripaphylus Richiardi, in Anonymous, 1878 and Paeon Wilson, 1919 prompting us to relegate Paeon to a junior subjective synonym of Tripaphylus. In the light of this synonymy the eight former species of Paeon are transferred to Tripaphylus as follows: T. ferox (Wilson, 1919) new combination, T. elongatus (Wilson, 1932) new combination, T. vassierei (Delamare Deboutteville & Nuñes-Ruivo, 1954) new combination, T. lobatus (Kirtisinghe, 1964) new combination, T. asymboli (Turner, Kyne & Bennett, 2003) new combination, T. versicolor (Wilson, 1919) new combination, T. australis (Kabata, 1993) new combination, and T. triakis (Castro Romero, 2001) new combination. Comparisons between terminology used in this report and that in the literature indicate that all transformed adult females of Tripaphylus probably possess a full complement of cephalic appendages and maxillipeds. All limbs, with the exception of the maxillae share a general morphological similarity to the corresponding appendages of conspecific males. The maxilla of the transformed adult female of Tripaphylus is a small digitiform protuberance associated with a swelling in some species.

A new genus of rhinebothriidean cestodes from batoid elasmobranchs, with the description of five new species and two new combinations.

Survey work of batoid elasmobranchs in the eastern Atlantic and Indo-Pacific revealed multiple species of a new genus of cestode. Stillabothrium Healy et Reyda gen. n. (Rhinebothriidea: Escherbothriidae) is unique in its possession of an even number of non-medial longitudinal septa in the posterior portion of the bothridia, resulting in a series of loculi that are longer than wide (i.e. vertically oriented) and are arranged in columns. Five new species of Stillabothrium are described, S. ashleyae Willsey et Reyda sp. n., S. davidcynthiaorum Daigler et Reyda sp. n., S. campbelli Delgado, Dedrick et Reyda sp. n., S. hyphantoseptum Herzog, Bergman et Reyda sp. n., S. jeanfortiae Forti, Aprill et Reyda sp. n., and two species are formally transferred to the genus, S. amuletum (Butler, 1987) comb. n., and S. cadenati (Euzet, 1954) comb. n., the latter of which is redescribed. The species differ in the configuration of the other bothridial septa and in proglottid anatomy. Species of Stillabothrium were found parasitising a total of 17 species of batoid elasmobranchs of the genera Dasyatis Rafinesque, Glaucostegus Bonaparte, Himantura Müller et Henle, Pastinachus Rüppell, Rhinobatos Linck and Zanobatus Garman, including several host species that are likely new to science. A phylogenetic hypothesis based on Bayesian analysis of 1 084 aligned positions of the D1-D3 region of 28S rDNA for 27 specimens representing 10 species of Stillabothrium and two outgroup species supported the monophyly of Stillabothrium. These results also supported morphologically determined species boundaries in all cases in which more than one specimen of a putative species was included in the analysis. Host specificity appears to vary across species of Stillabothrium, with the number of host species parasitised by each species of Stillabothrium ranging from one to four. The geographic distribution of species of Stillabothrium spans the eastern Hemisphere, including the eastern Atlantic (coastal Senegal) and several locations in the Indo-Pacific (coastal Vietnam, Borneo and Australia). In addition, Phyllobothrium biacetabulatum Yamaguti, 1960 is formally transferred into family Escherbothriidae, although its generic placement remains uncertain (species incertae sedis).

Two new species of Rhinebothrium (Cestoda: Rhinebothriidea) from granulated guitarfish Glaucostegus granulatus in the Gulf of Oman.

During a study of the rhinebothriideans of rays in the Gulf of Oman, two new species of Rhinebothrium Linton, 1890, Rhinebothrium kruppi sp. n. and R. persicum sp. n., were identified in Glaucostegus granulatus (Cuvier). Some significant features that distinguish R. kruppi sp. n. from R. persicum sp. n. include: scolex characteristics (hinged with 42-46 loculi vs. fusiform with 68-62 loculi), number of testes (4-5 vs. 20-27), genital pore position (61.1-76.9% of proglottid length vs. 47.2-63.3%), ovarian morphology (lobulated vs. follicular), cirrus-sac expansion (past midline of proglottid vs. limited to poral side of proglottid), vas deferens configuration (spanning posteriorly to near ovarian isthmus vs. to the level of ovarian anterior margins) and details of microthrix morphology. In addition, a combination of the aforementioned characteristics can be used to distinguish these two new species from other valid species of Rhinebothrium. These are the first species of rhinebothriidean cestodes to be described systematically from the Gulf of Oman, Iran. The two new species reported here increase the number of valid species of Rhinebothrium to 43.

Pigmentation patterns are useful for species identification of third-stage larvae of gnathiids (Crustacea: Isopoda) parasitising coastal elasmobranchs in southern Japan.

Previous studies from southern Japan reported larval stages of eight gnathiid isopod species parasitising coastal elasmobranchs. Since gnathiid larvae of these different species closely resembled each other, it was necessary to obtain specimens of free-living adult males for identification to the species level. This was achieved by allowing larvae of the final stage to moult into adult males. From these males, specimens of a species new to science were discovered and described here as Gnathia rufescens n. sp. The main differentiating characteristics of G. rufescens n. sp. are: (i) the apex of pleotelson is oval shaped; (ii) the dorsal sulcus is wide in the posterior part; and (iii) the article 3 of the pylopod is not reduced in the male. Additionally, this paper summarises the specific pigmentation patterns of third-stage larvae of the new species and eight previously described species. Furthermore, host records and host use by the gnathiids were summarised based on data from 158 hosts and over 4,500 gnathiid samples; these are discussed with a focus on host-specificity of the nine gnathiid species studied.

Morphological and molecular characterisation of Ditrachybothridium macrocephalum Rees, 1959 (Cestoda: Diphyllidea) from Galeus melastomus Rafinesque in the Western Mediterranean.

New morphological, molecular and ecological data for Ditrachybothridium macrocephalum Rees, 1959 (Cestoda: Diphyllidea) are presented and discussed based on specimens recovered from the blackmouth catshark Galeus melastomus Rafinesque (Scyliorhinidae) in the Western Mediterranean. A redescription of the plerocercus of this parasite is provided and new data on immature and mature worms including the first description of the eggs are reported, based on light and scanning electron microscopy observations. Analysis of 28S rDNA (domains D1-D3) sequences from plerocerci, immature and adult specimens revealed that they are conspecific with specimens from the North East Atlantic. Although previous authors considered that museum specimens identified as D. macrocephalum may represent more than one species, examination of type- and voucher material revealed no relevant morphological differences between museum specimens and the present material. Information on infection levels of D. macrocephalum is provided from a large number of host specimens (n = 170). This species was more abundant in juvenile than in adult hosts and on the middle slope than on the upper slope; this may be related to ontogenetic and bathymetric diet shifts of G. melastomus.

Ectoparasites of the Critically Endangered green sawfish Pristis zijsron and sympatric elasmobranchs in Western Australia.

This study reports the metazoan ectoparasite fauna of juvenile Critically Endangered green sawfish, Pristis zijsron, and sympatric elasmobranchs in Western Australia. Five parasite taxa were found on 76 screened P. zijsron: Caligus furcisetifer (Copepoda: Caligidae), Dermopristis pterophila (Monogenea: Microbothriidae), Branchellion plicobranchus and Stibarobdella macrothela (Hirudinea: Piscicolidae), and praniza larvae of an unidentified gnathiid isopod. Only C. furcisetifer and D. pterophila were common, exhibiting discrepant site-specificity, with C. furcisetifer occurring mostly on the head and rostrum, and D. pterophila around the pectoral and pelvic fins. Intensity of infection for C. furcisetifer and D. pterophila increased with host total length and was influenced by host sex, but in opposite directions; intensity of C. furcisetifer was greater on female P. zijsron, whereas intensity of D. pterophila was greater on males. In the Ashburton River, likelihood of infection for C. furcisetifer and D. pterophila on P. zijsron increased with time since substantial freshwater discharge events, suggesting decreased salinity impacts both taxa. In addition to P. zijsron, five other sympatric elasmobranch species were opportunistically screened for ectoparasites in the study area: the giant shovelnose ray, Glaucostegus typus, the eyebrow wedgefish, Rhynchobatus palpebratus, the nervous shark, Carcharhinus cautus, the lemon shark, Negaprion acutidens, and the graceful shark, Carcharhinus amblyrhynchoides. Caligus furcisetifer was found on R. palpebratus; no other parasites of P. zijsron were found on other sympatric elasmobranch species. Conversely, Perissopus dentatus (Copepoda: Pandaridae) was found on all three carcharhinids but not on batoid rays (P. zijsron, G. typus or R. palpebratus).

A retrospective study of disease in elasmobranchs.

This report reviews diseases of 1546 elasmobranchs representing at least 60 species submitted to Northwest ZooPath from 1994 to 2010. Cownose rays (Rhinoptera bonasus) (78), southern rays (Dasyatis americana) (75), dusky smooth-hounds (Mustelus canis) (74), bonnethead sharks (Sphyrna tiburo) (66), and bamboo sharks (Hemiscylliidae) (56) were the most commonly submitted species. Infectious/inflammatory disease was most common (33.5%) followed by nutritional (11.9%, mostly emaciation), traumatic (11.3%), cardiovascular (5.5%, mostly shock), and toxin-associated disease (3.7%). Bacterial infections (518/1546, 15%) included sepsis (136/518, 26%), dermatitis (7%), branchitis (6%), and enteritis (4%). Fungal infections (10/1546, 0.6%) included dermatitis (30%), hepatitis (30%), and branchitis (20%). Viral or suspected viral infections or disease processes (15/1546, 1%) included papillomatosis (47%), herpesvirus (20%), and adenovirus (7%). Parasitic infections (137/1546, 9%) included nematodiasis (36/137, 26%), ciliate infections (23%), trematodiasis (20%), coccidiosis (6%), myxozoanosis (5%), amoebiasis (4%), cestodiasis (1%), and flagellate infections (1%). Inflammation of unknown cause (401/1546, 26%) included enteritis (55/401, 14%), branchitis (9%), encephalitis (9%), and dermatitis (7%). Traumatic diseases (174/1546, 11.3%) included skin trauma (103/174, 60%), stress/maladaptation (9%), and gut trauma (7%). Toxicoses (57/1546, 4%) included toxic gill disease (16/57, 26%), gas bubble disease (19%), fenbendazole (7%), ammonia (7%), chlorine (5%), and chloramine (3%). Species trends included visceral nematodiasis in black-nosed sharks (Carcharhinus acronotus) (55%); sepsis in dusky smooth-hounds (41%), blue-spotted stingrays (36%), southern rays (36%), and wobeggong sharks (Orectolobus spp) (69%); emaciation in bamboo (33%) and bonnethead (32%) sharks and freshwater stingrays (Potamotrygon motoro) (32%); and trauma in bonnethead sharks (30%).

Pristiorhynchus palmi n. g., n. sp. (Cestoda: Trypanorhyncha) from sawfishes (Pristidae) off Australia, with redescriptions and new records of six species of the Otobothrioidea Dollfus, 1942.

A new genus of trypanorhynch cestodes, Pristiorhynchus n. g. (Otobothrioidea: Otobothriidae), is described from two species of modern sawfishes (Pristidae) from off northern Australia. Pristiorhynchus palmi n. g., n. sp. is characterised by an acraspedote scolex with two bothria, paired bothrial pits on the posterior margins of each bothrium, the absence of gland-cells within the bulbs and prebulbar organs, a retractor muscle inserting at the posterior region of the elongate bulbs, a characteristic basal tentacular armature with dispersed billhooks and a heteroacanthous atypical metabasal armature with five principle and three intercalary hooks. Furthermore, redescriptions are provided for Symbothriorhynchus tigaminacantha Palm, 2004, Parotobothrium balli (Southwell, 1929) and Pseudotobothrium arii (Bilqees & Shaukat, 1976). Observations of adult worms revealed novel information on the segment morphology, which has not been described for these three species. Specimens of Proemotobothrium linstowi (Southwell, 1924), Pr. southwelli Beveridge & Campbell, 2001 and Fossobothrium perplexum Beveridge & Campbell, 2005 collected from elasmobranchs from several sampling localities off Australia revealed additional information on host range and geographical distribution.