Citizen science data opens multiple avenues for iridovirus research and prompts first detection of Invertebrate iridescent virus 31 in Australia.

From citizen science data we report the first records of blue to violet-colored oniscideans (Oniscidea: Isopoda), indicating potential invertebrate iridescent virus (IIV; Betairidovirinae: Iridoviridae) infection: in Africa, South America, and Oceania; and of the new hosts Armadillidium nasatum and Balloniscus sellowii. DNA sequencing of indigo Porcellio scaber confirms the presence of Invertebrate iridescent virus 31 in Australia. Beyond the Oniscidea, new, putative IIV hosts are identified: hoverfly pupae (Eristalinae), a tortrix moth larva (Phaecasiophora niveiguttana), and a millipede (Harpaphe haydeniana). In addition, the purported positive correlation between virion diameter and wavelength of iridescence is analyzed qualitatively for the first time.

Some adult and larval nematodes from fishes off New Caledonia.

A collection of nematodes from the Muséum National d'Histoire Naturelle (National Museum of Natural History), Paris, France, was studied. The nematodes had previously been collected from a range of marine fish hosts. The aim of this study was to investigate the identity of these nematodes. Detailed body measurements of the nematodes were taken via light microscopy and where possible first and second internal transcribed spacers (ITS-1 and ITS-2) of ribosomal DNA were subjected to PCR, purified and sequenced. Six species and three larval types were found from a range of fish species and included 13 new host records and two new geographical records. Of the taxa found, Hysterothylacium kajikiae is the only species which may have zoonotic potential. The majority of host fish in this study are edible species, commercially and recreationally fished and frequently incorporated into the cuisine of New Caledonia as raw fish dishes. This study will allow better understanding of the diversity, life cycles, distribution and host-parasite relationships in the New Caledonia area.

Occurrence of anisakid parasites in marine fishes and whales off New Caledonia.

Anisakid nematodes are the most infamous parasites occurring in seafood with ability to infect humans. In the present study, the infective stages of five anisakid larval types, including Anisakis types I and III, Terranova types I and II and Contracaecum larval type, as well as adult Anisakis paggiae are reported from 16 host species from New Caledonian waters. The specific identity of the larval types was investigated using ITS sequence data. Anisakis larval types I and III were identified as Anisakis typica and Anisakis brevispiculata, respectively, based on identical ITS sequences. However, the specific identity of the Terranova larval types and Contracaecum larval type remains unknown until a matching ITS sequence from a well-identified adult is available. Several fish host species are reported for the first time for anisakid larval types found in this study. Considering that third-stage larvae of anisakids are known to be the infective stage of the parasite for humans and the popularity of seafood in New Caledonia, presence of these parasites in New Caledonian fish is of high importance in terms of public health and raising awareness among various stakeholders. Although adult nematodes in the present study were identified as Anisakis paggiae, the spicule length is shorter in our specimens and falls within the range reported for Anisakis oceanicus previously reported in Pacific waters from black fish (genus Globicephala) and later synonymised with Anisakis physeteris. However, our specimens are different from A. physeteris in morphology of ventriculus. Anisakis paggiae has been reported from whales in southern hemisphere and this is the first report from the Pacific regions.

Characterisation of Ascaridoid larvae from marine fish off New Caledonia, with description of new Hysterothylacium larval types XIII and XIV.

Here we report occurrence of six different morphotypes of ascaridoid type larvae from 28 species of fish collected from New Caledonian waters. The larvae were morphologically identified as Anisakis type I, Hysterothylacium type VI and new larval types XIII and XIV, Raphidascaris larval type and Terranova larval type II. Representatives of each morphotype were subjected to the amplification of the second internal transcribed spacers (ITS-2) of ribosomal DNA (rDNA) and those sequences were compared with ITS-2 sequences of other ascaridoid nematodes previously deposited in GenBank. ITS-2 sequences of Anisakis larval type I were identical to those of A. typica. ITS-2 sequences of Hysterothylacium larval type VI in the present study were identical to those previously found in Eastern Australian waters. No match was found for ITS-2 sequences of Hysterothylacium larval types XIII and XIV; therefore, the specific identities of these larval types remain unclear. ITS-2 sequences of Raphidascaris larval type were identical to those of R. trichiuri, which have previously been reported in Taiwanese waters. Terranova larval type II in the present study had identical ITS-2 sequences with Terranova larval types reported from Australian waters, however, the specific identity is unknown. This taxonomic work is essential if further research on these zoonotic parasites is to be effective. This includes investigations into such aspects as life cycle studies, impacts on human health and risk assessment for their transmission to humans.