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Ten Southern Hemisphere cephalopod species from six families collected from six localities in western, southern and eastern Australia were examined for dicyemid parasites. A total of 11 dicyemid species were recorded, with three cephalopod species uninfected, four infected by one dicyemid species and three infected by multiple dicyemid species. Dicyemid species prevalence ranged from 24-100%, with observed infection patterns explored due to host size, host life history properties, host geographical collection locality and inter-parasite species competition for attachment sites, space and nutrients. Left and right renal appendages were treated as separate entities and four different patterns of infection by asexual and sexual dicyemid stages were observed. The detection within a single host individual of asexual dicyemid stages in one renal appendage and sexual dicyemid stages in the other renal appendage supported the notion that developmental cues mediating stage transition are parasite-controlled, and also occurs independently and in isolation within each renal appendage. Our study exploring dicyemid parasite fauna composition in relation to cephalopod host biology and ecology therefore represents a thorough, broad-scale taxonomic analysis that allows for a greater understanding of dicyemid infection patterns.

The elongated encased spermatophores of the capsalid (entobdelline) monogeneans Neoentobdella diadema (Monticelli, 1902) Kearn et Whittington, 2005 and N. apiocolpos (Euzet et Maillard, 1967) Kearn et Whittington, 2005 have been found attached by their proximal ends to the region of the vaginal opening, with the bulk of the spermatophore projecting from the vagina and therefore lying outside the body. In spite of previous reports, no spermatophores were found projecting from the common genital opening and if spermatophore exchange is as rapid as it is in the related entobdelline Entobdella soleae, then the chances of finding a spermatophore in this location are small. In N. diadema and N. apiocolpos it is likely that sperm enters the vagina through the open proximal end of an attached spermatophore, after which the empty spermatophore case is probably discarded. There is no evidence for a previous proposal that the whole spermatophore is engulfed by the vagina followed by digestion of the case to release the sperm. Three specimens of N. diadema were found each with two spermatophore cases projecting from the vagina and a specimen of N. apiocolpos carried three cases. Assuming that each parasite is able to donate or receive only one spermatophore at each mating, then the presence of one spermatophore does not prevent a further mating and acceptance of a fresh spermatophore. In spite of differences between the spermatophores of E. soleae and N. diadema/N. apiocolpos, the events of spermatophore exchange may be similar.

Branchotenthes octohamatus sp. n. (Monogenea: Hexabothriidae) is described from the gills of the southern fiddler ray, Trygonorrhina fasciata Müller et Henle (Elasmobranchii: Rhinobatidae), off Adelaide, South Australia. It is distinguished from the type species, Branchotenthes robinoverstreeti Bullard et Dippenaar, 2003, by producing eggs that are joined end to end forming a chain, in the morphology of the male copulatory organ that has a pronounced constriction in duct diameter between proximal and distal regions, the possession of a thin muscular layer surrounding the proximal part of the male copulatory organ and distal region of the vaginae, and by the absence of a raised process on the shaft of the hamulus. An amended generic diagnosis is provided and the reliability of sperm duct number as a generic character is discussed. The oncomiracidium of B. octohamatus is also described and is the first monogenean to be described with only eight hooklets in the larval haptor. This discovery of eight hooklets may be important for higher-level monogenean evolutionary hypotheses.

Dendromonocotyle species (Monogenea: Monocotylidae) are the only monocotylids to parasitize the skin of chondrichthyan hosts. Currently 11 species are recorded from the skin of ray species in the Dasyatidae, Myliobatidae and Urolophidae. There have been increasing reports of Dendromonocotyle outbreaks on rays kept in public aquaria. This paper provides a broad review of Dendromonocotyle that should assist taxonomists and aquarists with species identification and help decisions on potential control methods for Dendromonocotyle infections. The taxonomy and host-specificity of Dendromonocotyle are discussed and a key to current species is provided. We summarise what little is known about the biology of Dendromonocotyle including egg embryonation and hatching, feeding, camouflage and reproduction. The efficacy of freshwater baths, chemical treatments and biological control measures such as the use of cleaner fish for Dendromonocotyle is also discussed. We demonstrate that effective control of Dendromonocotyle on captive rays is hampered by the lack of basic biological data on the life cycle of the parasites. A case history is provided outlining the success of a public aquarium (Underwater World, Mooloolaba, Queensland, Australia) in managing D. pipinna infections on captive Taeniura meyeni without chemical intervention simply by taking measures to reduce host stress.

Secreted anterior adhesives, used for temporary attachment to epithelial surfaces of fishes (skin and gills) by some monogenean (platyhelminth) parasites have been partially characterised. Adhesive is composed of protein. Amino acid composition has been determined for seven monopisthocotylean monogeneans. Six of these belong to the Monocotylidae and one species, Entobdella soleae (van Beneden et Hesse, 1864) Johnston, 1929, is a member of the Capsalidae. Histochemistry shows that the adhesive does not contain polysaccharides, including acid mucins, or lipids. The adhesive before secretion and in its secreted form contains no dihydroxyphenylalanine (dopa). Secreted adhesive is highly insoluble, but has a soft consistency and is mechanically removable from glass surfaces. Generally there are high levels of glycine and alanine, low levels of tyrosine and methionine, and histidine is often absent. However, amino acid content varies between species, the biggest differences evident when the monocotylid monogeneans were compared with E. soleae. Monogenean adhesive shows similarity in amino acid profile with adhesives from starfish, limpets and barnacles. However, there are some differences in individual amino acids in the temporary adhesive secretions of, on the one hand, the monogeneans and, on the other hand, the starfish and limpets. These differences may reflect the fact that monogeneans, unlike starfish and barnacles, attach to living tissue (tissue adhesion). A method of extracting unsecreted adhesive was investigated for use in further characterisation studies on monogenean glues.

Ten Southern Hemisphere cephalopod species from six families collected from six localities in western, southern and eastern Australia were examined for dicyemid parasites. A total of 11 dicyemid species were recorded, with three cephalopod species uninfected, four infected by one dicyemid species and three infected by multiple dicyemid species. Dicyemid species prevalence ranged from 24-100%, with observed infection patterns explored due to host size, host life history properties, host geographical collection locality and inter-parasite species competition for attachment sites, space and nutrients. Left and right renal appendages were treated as separate entities and four different patterns of infection by asexual and sexual dicyemid stages were observed. The detection within a single host individual of asexual dicyemid stages in one renal appendage and sexual dicyemid stages in the other renal appendage supported the notion that developmental cues mediating stage transition are parasite-controlled, and also occurs independently and in isolation within each renal appendage. Our study exploring dicyemid parasite fauna composition in relation to cephalopod host biology and ecology therefore represents a thorough, broad-scale taxonomic analysis that allows for a greater understanding of dicyemid infection patterns.

The Gyrodactylidae is a diverse family of predominantly viviparous monogeneans (for familial status of oviparous genera see Boeger W.A, Kritsky D.C, Belmont-Jegu E. 1994: J. Helminthol. Soc. Wash. 61: 34-44) found on a wide variety of fish taxa globally. Gyrodactylids are thought to be more common in high latitude environments and conversely less common in low latitude environments such as the Great Barrier Reef (GBR) (Rohde K. 1985: Hydrobiologia 127: 197201). Most research on gyrodactylids has been carried out in temperate areas of Europe and North America, but the gyrodactylid fauna of the Indo-Pacific Ocean remains comparatively unknown. In Australia, for example, few of the estimated 3000 coastal marine fish species (Kuiter R.H. 1996: Guide to Sea Fishes of Australia. New Holland, Sydney, 433 pp.) have been examined thoroughly for small ectoparasites such as gyrodactylids. There is the potential, therefore, for a diverse, undiscovered gyrodactylid fauna on Australian marine fishes. This note presents the results of a survey for these parasites from coastal marine fishes from Queensland, Australia. Our survey has resulted in the discovery of several new gyrodactylid species, and descriptions of some of these have already been published (Ernst I., Whittington I.D., Jones M.K. 2000: Syst. Parasitol. 45: 61-73; Ernst I., Jones M.K., Whittington I.D. 2001: J. Nat. Hist. 35: 313-340). Fishes were collected between 1995 and 2000 by beach seine, cast net, line fishing, anaesthetic (clove oil) or spearfishing. On the GBR, fishes were collected at Heron and Wistari Reefs (23°27’S, 151°55’E) in the southern region and Eagle Islet (14°42’S, 145°23’E) and Lizard Island (14°40’S, 145°28’E) in the northern region. Fishes were collected in south-east Queensland at Amity Point (27°45’S, 153°26’E), Dunwich (27°30’S, 153°24’E), Manly (27°28’S, 153°11’E), Redcliffe (27°14’S, 153°07’E), Wellington Point (27°28’S, 153°11’E), Noosa (26°23’S, 153°07’E), Nudgee Beach (27°21’S, 153°06’E) and Southport Broadwater (27°58’S, 153°25’E). Fishes were identified using the books of Randall et al. (Randall J.E., Allen G.R., Steene R.C. 1990, 1998: Fishes of the Great Barrier Reef and Coral Sea. Editions 1 and 2. Crawford House Press, Bathurst, 507 pp. and 557 pp.), Kuiter (Kuiter R.H. 1993: Coastal Fishes of South-Eastern Australia. Crawford House Press, Bathurst, 437 pp.) and Myers (Myers R.F. 1991: Micronesian Reef Fishes. Coral Graphics, Guam, 298 pp.). Live fish of the same species were placed in individual containers of seawater for transport to the laboratory where they were held in separate aquaria until dissection. Fish were killed and dissected and worms were mounted as described in Ernst et al. (2000, op. cit.). Specimens are deposited in the Queensland Museum (QM), P.O. Box 3300, Brisbane, Queensland 4101, Australia. We examined 501 marine teleosts comprising 104 species in 37 families (Table 1). Gyrodactylids were found on 20 fish species (19% of those examined) from 9 families. At least 16 different species of gyrodactylids were found in this survey including: 7 species of Gyrodactylus von Nordmann, 1832, 7 species of Acanthoplacatus Ernst, Jones et Whittington, 2001, 1 species of Anacanthocotyle Kritsky et Fritts, 1970 and 1 species of Polyclithrum Rogers, 1967 (Table 2). Due to insufficient material, the specific status could not be determined for a single specimen of Gyrodactylus from a goby and specimens of Acanthoplacatus from two siganid species (Table 2). It is possible that these specimens represent three additional gyrodactylid species. Therefore, the gyrodactylids collected in this survey represent between 16 and 19 species. Those specimens ascribed specific status (Table 2) are considered to be new species (see also Ernst et al. 2001, op. cit.) and constitute a major addition to the known gyrodactylid fauna of the world which is estimated to include over 400 species (see Harris P.D. 1993: Bull. Fr. Peche Piscic. 328: 546). When interpreting these data, two sources of bias should be borne in mind. First, we did not examine species in some potential host families that have been studied for monogeneans previously and which are not reported as hosts of gyrodactylids (e.g. Lethrinidae, Serranidae; see Whittington I.D. 1998: Int. J. Parasitol. 28: 1481-1493). Secondly, only a few specimens of some fish species were examined (Table 1). Of 104 marine fish species examined in this survey, 33 species are represented by 5 or more specimens and only 13 species are represented by 10 or more specimens (Table 1). With sample sizes of 5 and 10 individuals, parasite prevalences of up to 45 and 26%, respectively (95% confidence limit) could go undetected (see Post R.J., Millest A.L. 1991: Parasitol. Today 7: 141). Therefore the reported absence of gyrodactylids from some fish species should be interpreted cautiously because only relatively prevalent gyrodactylid species are likely to have been detected. This is not the first survey for monogeneans in marine waters of Australia. Rohde (1985, op. cit.) presented the results of surveys for monogeneans from the northern GBR where he examined 239 specimens of 56 fish species, the southern GBR where he examined 392 specimens of 74 fish species and northern New South Wales (NSW) where he examined 1859 specimens of 45 fish species. Gyrodactylid species were poorly represented, with only one or two unidentified species recorded from the southern GBR and one unidentified species recorded in northern NSW. Rohde (1985, op. cit.) compared these results with surveys for monogeneans from other geographic areas. He presented data showing that FOLIA PARASITOLOGICA 48: 165-168, 2001

Dendromonocotyle colorni sp. n. (Monogenea: Monocotylidae) is described from the dorsal skin surface of two specimens of Himantura uarnak (Forsskål) kept at the Eilat Underwater Observatory in Israel. Dendromonocotyle colorni is distinguished from the other eight species in the genus by the morphology of the terminal papillar sclerite on the haptor, the distal portion of the male copulatory organ and the morphology of the vagina. The development of the male copulatory organ is detailed for D. colorni and the adaptations of species of Dendromonocotyle to life on the dorsal skin surface of rays are discussed. Dendromonocotyle octodiscus Hargis, 1955 was identified from the dorsal skin surface of the southern stingray Dasyatis americana Hildebrand et Schroeder off Bimini, Bahamas and represents a new host record.

Heliocotyle ewingi sp. n. (Monogenea: Monocotylidae) is described from the gills of Myliobatis australis Macleay, 1881 (Myliobatididae) collected from Norfolk Bay near Hobart, Tasmania, Australia. Heliocotyle ewingi can be distinguished readily from the only other species in the genus, Heliocotyle kartasi Neifar, Euzet et Ben Hassine, 1999, by the presence of a single pseudoseptum on each of the peripheral loculi except the posteriormost, eyespots and by the morphology of the male copulatory organ which is a short, straight sclerotised tube which lacks a sclerotised accessory piece. The generic diagnosis is revised to accommodate the new species and the anterior glands are discussed.

Dioncopseudobenedenia Yamaguti, 1965 (Monogenea: Capsalidae) is redefined. Dioncopseudobenedenia kala Yamaguti, 1965 (type species) is redescribed from type material from Hawaii and from new specimens from Heron Island, Queensland, Australia and New Caledonia. We made detailed observations on D. macracantha Yamaguti, 1968 from type material from Hawaii, and from new material from Heron Island and New Caledonia. Dioncopseudobenedenia ancoralis sp. n. is described from the gill chamber of Siganus lineatus (Valenciennes) from Green Island and Heron Island, Australia and from New Caledonia. This study confirms that only one pair of large central sclerites is present on the haptor in Dioncopseudobenedenia species. The male copulatory organ in species of Dioncopseudobenedenia is a penis contained in a fluid-filled space (= penis canal) with weakly muscular walls. Dioncopseudobenedenia kala and D. ancoralis bear a sclerite at the tip of the penis. In D. macracantha, the structure of the penis, which has no terminal sclerite, indicates it may combine the functions of a penis and a cirrus. Dioncopseudobenedenia is compared with Calicobenedenia Kritsky et Fennessy, 1999, the other capsalid genus with a single pair of large sclerites on the haptor. The large haptoral sclerites in species of Dioncopseudobenedenia resemble accessory sclerites, whereas those of C. polyprioni Kritsky et Fennessy, 1999 resemble hamuli. Observations of oncomiracidia confirmed that the large haptoral sclerites in D. kala are accessory sclerites. Haptoral morphology suggests that different Dioncopseudobenedenia spp. employ different means of attachment. Mating behaviour was observed twice between two different pairs of D. kala specimens from Heron Island. Two preserved specimens from Noumea, New Caledonia had structures near the dorsal vaginal pore that we interpret as spermatophores. This is the first report of spermatophores in a capsalid inhabiting the gill chamber. The geographic distribution of Dioncopseudobenedenia spp. is discussed.

International audience; Over a 7-year period, parasites have been collected from 28 species of groupers (Serranidae, Epinephelinae) in the waters off New Caledonia Host-parasite and parasite-host lists are provided, with a total of 337 host-parasite combinations, including 146 parasite identifications at the species level Results are included for isopods (5 species), copepods (19) monogeneans (56), digeneans (28), cestodes (12) and nematodes (12) When results are restricted to those 14 fish species for which more than five specimens were examined and to parasites identified at the species level, 109 host-parasite combinations were recorded, with 63 different species, of which monogeneans account for half (32 species), and an average of 4 5 parasite species per fish species Digenean records were compared for 16 fish species shared with the study of Cribb et al (2002), based on a total of 90 parasite records identified at the species level, New Caledonia has 17 new records and only seven species were already known from other locations We hypothesize that the present results represent only a small part of the actual biodiversity, and we predict a biodiversity of 10 different parasite species and 30 host-parasite combinations per serranid A comparison with a study on Heron Island (Queensland, Australia) by Lester and Sewell (1989) was attempted of the four species of fish in common and in a total of 91 host-parasite combinations, only six parasites identified at the species level were shared This suggests strongly that insufficient sampling impairs proper biogeographical or ecological comparisons Probably only 3% of the parasite species of coral reef fish are already known in New Caledonia

Two new species of entobdelline (capsalid) monogeneans are described from the skin of Australian dasyatid stingrays, namely Neoentobdella cribbi sp. n., a small parasite from the estuarine stingray, Dasyatis fluviorum Ogilby (Elasmobranchii: Dasyatidae) and Neoentobdella baggioi sp. n., a relatively large parasite from the porcupine ray, Urogymnus asperrimus (Bloch et Schneider) (Elasmobranchii: Dasyatidae). A striking feature of both of these new parasite species is a pad, possibly located within the genital atrium, armed with rows of closely spaced, rod-shaped microsclerites. Both species also possess a muscular papilla in the genital tract and a club-shaped structure near the common genital opening on the left lateral margin of the body. In N. cribbi, the latter feature is large and located anterior to the genital pad and in N. baggioi, it is small and located in a more posterior position. Similar embellishments in the genital area occur in N. natans Kearn et Whittington, 2005 and in N. parvitesticulata Kearn et Whittington, 2005, while other species (e.g. N. garneri Whittington et Kearn, 2009 and N. taiwanensis Whittington et Kearn, 2009) lack these features and differ also in functional aspects of the male copulatory apparatus and the haptor. Separate generic status for these two groupings is indicated, but must await a comparative and comprehensive review of all Neoentobdella spp.

Myliocotyle borneoensis sp. n. and M. multicrista sp. n. (Monocotylidae: Heterocotylinae) are described from the gills of the mottled eagle ray, Aetomylaeus maculatus (Gray), and the banded eagle ray A. nichofii (Bloch et Schneider) (Mylio- batidae), respectively, collected from the northern coast of Malaysian Borneo. These are the first monogeneans to be described on elasmobranchs from Borneo. The formerly monotypic Myliocotyle (for M. pteromylaei) was distinguished from other mono- cotylids by the distribution and morphology of the eight sclerotised dorsal haptoral accessory structures and the morphology of the male copulatory organ. However, we have determined that M. pteromylaei has ten structures on the dorsal surface of the haptor. Myliocotyle borneoensis is distinguished from M. pteromylaei by the morphology of the male copulatory organ and its accessory piece. Myliocotyle multicrista has 12 sclerotised dorsal haptoral accessory structures and a male copulatory organ with two accessory pieces. Additional sclerotised ridges across the ventral surfaces of each loculus (except the posterior-most pair) are also present in M. multicrista. The diagnosis for Myliocotyle is revised given our discovery of additional dorsal haptoral accessory structures in the type species and to accommodate other new characters of the two new species. Anterior secretions of Myliocotyle are discussed.

The Capsalidae are monogeneans parasitizing 'skin', fins and gills of marine fishes. Some capsalids are pathogenic to cultivated fish and a few have caused epizootic events. It is a cosmopolitan family with broad host associations (elasmobranchs and teleosts, including sturgeons). Approximately 200 capsalid species are placed in nine subfamilies and 44-46 genera, some of which are well known (Benedenia, Capsala, Entobdella, Neobenedenia). Sturgeons host two capsalid species (Nitzschiinae) and 15 species in five genera are reliably reported from elasmobranchs. The combination of ancient (shark, ray, sturgeon) and modern (teleost) host fish lineages indicates that capsalid evolution is likely a blend of coevolution and host-switching, but a family phylogeny has been lacking due to deficient knowledge about homologies. The current phenetic subfamilial classification is discussed in detail using a preliminary phylogeny generated from large subunit ribosomal DNA sequence data from representatives of five subfamilies. Monophyly of the Capsalidae is supported by possession of accessory sclerites. Hypotheses are proposed for the possible radiation of capsalids. A suggestion that Neobenedenia melleni, a pathogenic species atypical due to its broad host-specificity (>100 host teleost species from >30 families in five orders), may be a complex of species is supported from genetic evidence. This may explain peculiarities in biology, taxonomy, host associations and geographic distribution of N. 'melleni' and has implications for fish health. Holistic studies using live and preserved larval and adult capsalid specimens and material for genetic analysis are emphasised to further determine identity, phylogeny and details of biology, especially for pathogenic species.