Some Copepoda Parasitic on Fishes of the New Zealand Region

<p>Material representing 38 species of parasitic Copepoda, Order Caligoida, from New Zealand marine fishes, belonging to 20 genera and six families is discussed. Except for Lepeophtheirus erecsoni Thomson, of which only damaged material was available, the species are described and figured in detail. Previous records from New Zealand waters are discussed. The name Caligus vicarius is proposed for C. longicaudatus Brady which is preoccupied. Species examined and their hosts are as follows (new hosts for previously known species, and previously known species newly recorded from New Zealand are marked with asterisks) - Caligidae: Caligus brevis Shiinox on Pseudolabrus pittensisx, P. milesx and P. celidotusx; C. aesopus Wilsonx on Seriola grandisx; C. pelamydis Kroyerx on Thyrsites atunx; C. buechlerae Hewitt on Tripterygion sp.; Lepeophtheirus erecsoni Thomson on Latridopsis ciliaris; L. scutiger Shiinox on Pseudolabrus pittensisx, P. milesx and P. celidotusx; L. insignis Wilsonx on Mola mola; L. polyprioni Hewitt on Polyprion oxygenios and P. moeone; L. argentus Hewitt on Hyperoglyphe porosa; L. heegaardi Hewitt on Lepidopus caudatus; L. distinctus Hewitt on Genypterus blacodes; Euyphoridae: Gloiopotes huttoni (Thomson) on Makaira mitsukurii and M. marlina; Elytrophora brachyptera Gerstaekerx on Thunnus alalunga and. T. maccoyix; Pandaridae: Nesippus orientalis Hellerx on Mustelus antarcticus and Notorhynchus pectorosusx; N. borealis (Steenstrup and Lutken)x on Isurus oxyrinchusx; Dinemoura latifolia Steenstrup and Lutken on Carcharodon carcharias, Isurus oxyrinchus and Galeorhinus australis; D. producta (Muller) on Cetorhinus maximus and Carcharodon carcharias; Demoleus latus Shiinox on Squalus acanthiasx; Echthrogaleus braccatus (Dana) on an unrecorded host; E. coleoptratus (Guerin)x on Prionace glauca and Lamna nasus; E. denticulatus Smith on an unrecorded host; Phyllothyreus cornutus (Milne-Edwards)x on Isurus oxyrinchus; Pandarus bicolor Leachx on Squalus acanthias, Galeorhinus australisx, Notorhynchus pectorosusx and Cyprimulus sp.x; P. cranchii Leach on Galeorhinus australisx and Isurus oxyrinchus; Perissopus dentatus Steenstrup and Lutkenx on a hammerhead shark; Cecropidae: Cecrops latreillii Leach on Mola mola; Eudactylinidae: Nemesis lamna Rissox on Carcharodon carcharias, Cetorhinus maximus and Isurus oxyrinchus; N. robusta (van Beneden)x on Alopias vulpinus; Congericola pallidus van Benedenx on Conger vereauxix Dichelesthiidae; Pseudocycnus appendiculatus Hellerx on Thunnus alalunga; a new species of Hatschekia on Allomycterus jaculiferus; a further new species of Hatschekia on Lepidopus caudatus; Anthosomidae: a new species of Pseudolernanthropus on Thyrsites atun and Jordanidia solandri; a new species of Lernanthropus on Seriolella brama; Aethon percis (Thomson) on Parapercis coelias; two new species of Aethon on Cheilodactylus macropterus and Latridopus caudatues; Anthosoma crassum (Abildgaard) on Carcharodon carcharias, Isurus oxyrinchus, Lamna nasus and Galeorhinus galeusx; this collection includes all species belonging to these families which have previously and reliably been recorded from New Zealand waters, and of which adequate descriptions exist. The similarities of the cephalic appendages of caligoid copepods to those of free living copepods is discussed. The biogeographical relationships of the species here recorded are considered and it is concluded that many of these species, particularly those parasitic on elasmobranchs, are widespread, and that many of those with apparently restricted distributions may become known from other regions, especially when the little investigated parasite faunas of fishes from the South Pacific and South Atlantic become more fully known; the hosts from which the present species have been recorded are compared; it is shown that species occurring on elasmobranchs are confined to this but show little host specificity within it; teleost parasites may be restricted to one host species, one host genus, one host family, or to host families with systematic or ecological affinities; Cecrops latreillii is unique among these parasites in occurring on three quite different and apparently unrelated host species.</p>

Some Copepoda Parasitic on Fishes of the New Zealand Region

<p>Material representing 38 species of parasitic Copepoda, Order Caligoida, from New Zealand marine fishes, belonging to 20 genera and six families is discussed. Except for Lepeophtheirus erecsoni Thomson, of which only damaged material was available, the species are described and figured in detail. Previous records from New Zealand waters are discussed. The name Caligus vicarius is proposed for C. longicaudatus Brady which is preoccupied. Species examined and their hosts are as follows (new hosts for previously known species, and previously known species newly recorded from New Zealand are marked with asterisks) - Caligidae: Caligus brevis Shiinox on Pseudolabrus pittensisx, P. milesx and P. celidotusx; C. aesopus Wilsonx on Seriola grandisx; C. pelamydis Kroyerx on Thyrsites atunx; C. buechlerae Hewitt on Tripterygion sp.; Lepeophtheirus erecsoni Thomson on Latridopsis ciliaris; L. scutiger Shiinox on Pseudolabrus pittensisx, P. milesx and P. celidotusx; L. insignis Wilsonx on Mola mola; L. polyprioni Hewitt on Polyprion oxygenios and P. moeone; L. argentus Hewitt on Hyperoglyphe porosa; L. heegaardi Hewitt on Lepidopus caudatus; L. distinctus Hewitt on Genypterus blacodes; Euyphoridae: Gloiopotes huttoni (Thomson) on Makaira mitsukurii and M. marlina; Elytrophora brachyptera Gerstaekerx on Thunnus alalunga and. T. maccoyix; Pandaridae: Nesippus orientalis Hellerx on Mustelus antarcticus and Notorhynchus pectorosusx; N. borealis (Steenstrup and Lutken)x on Isurus oxyrinchusx; Dinemoura latifolia Steenstrup and Lutken on Carcharodon carcharias, Isurus oxyrinchus and Galeorhinus australis; D. producta (Muller) on Cetorhinus maximus and Carcharodon carcharias; Demoleus latus Shiinox on Squalus acanthiasx; Echthrogaleus braccatus (Dana) on an unrecorded host; E. coleoptratus (Guerin)x on Prionace glauca and Lamna nasus; E. denticulatus Smith on an unrecorded host; Phyllothyreus cornutus (Milne-Edwards)x on Isurus oxyrinchus; Pandarus bicolor Leachx on Squalus acanthias, Galeorhinus australisx, Notorhynchus pectorosusx and Cyprimulus sp.x; P. cranchii Leach on Galeorhinus australisx and Isurus oxyrinchus; Perissopus dentatus Steenstrup and Lutkenx on a hammerhead shark; Cecropidae: Cecrops latreillii Leach on Mola mola; Eudactylinidae: Nemesis lamna Rissox on Carcharodon carcharias, Cetorhinus maximus and Isurus oxyrinchus; N. robusta (van Beneden)x on Alopias vulpinus; Congericola pallidus van Benedenx on Conger vereauxix Dichelesthiidae; Pseudocycnus appendiculatus Hellerx on Thunnus alalunga; a new species of Hatschekia on Allomycterus jaculiferus; a further new species of Hatschekia on Lepidopus caudatus; Anthosomidae: a new species of Pseudolernanthropus on Thyrsites atun and Jordanidia solandri; a new species of Lernanthropus on Seriolella brama; Aethon percis (Thomson) on Parapercis coelias; two new species of Aethon on Cheilodactylus macropterus and Latridopus caudatues; Anthosoma crassum (Abildgaard) on Carcharodon carcharias, Isurus oxyrinchus, Lamna nasus and Galeorhinus galeusx; this collection includes all species belonging to these families which have previously and reliably been recorded from New Zealand waters, and of which adequate descriptions exist. The similarities of the cephalic appendages of caligoid copepods to those of free living copepods is discussed. The biogeographical relationships of the species here recorded are considered and it is concluded that many of these species, particularly those parasitic on elasmobranchs, are widespread, and that many of those with apparently restricted distributions may become known from other regions, especially when the little investigated parasite faunas of fishes from the South Pacific and South Atlantic become more fully known; the hosts from which the present species have been recorded are compared; it is shown that species occurring on elasmobranchs are confined to this but show little host specificity within it; teleost parasites may be restricted to one host species, one host genus, one host family, or to host families with systematic or ecological affinities; Cecrops latreillii is unique among these parasites in occurring on three quite different and apparently unrelated host species.</p>

Drivers of Spatial Distributions of Basking Shark (Cetorhinus maximus) in the Southwest Pacific

Basking sharks (Cetorhinus maximus) were widely reported throughout New Zealand waters. Once commonly observed, and sometimes in large numbers, basking sharks are now infrequently reported. Basking shark observations are known to be highly variable across years, and their distribution and occurrence have been shown to be influenced by environmental predictors such as thermal fronts, chl-a concentration, and the abundance of prey (zooplankton). Little is known of basking sharks in the South Pacific and more information on distribution, habitat use, and migratory patterns is required to better understand the species’ regional ecology. Here, we used bootstrapped Habitat Suitability Models [HSM, ensembled from Boosted Regression Tree (BRT) and Random Forest (RF) models] to determine the drivers of basking shark distribution, predict habitat suitability and estimated uncertainty in the South Pacific for the first time. High−resolution environmental (1 km2 grid resolution) and biotic data, including inferred prey species, and all available basking shark records across New Zealand’s Exclusive Economic Zone (EEZ) were included in the ensemble HSMs. The most influential driver of modeled basking shark distribution was vertical flux of particulate organic matter at the seabed, which may indicate higher levels of primary production in the surface ocean and higher prey density in the mesopelagic zone and at the seafloor. The BRT and RF models had good predictive power (AUC and TSS &gt; 0.7) and both models performed similarly with low variability in the model fit metrics. Areas of high basking shark habitat suitability included the east and west coasts of the South Island, Puysegur Ridge, and Auckland Island slope. The outputs produced here could be incorporated into future management framework for assessing threat and conservation needs (e.g., spatially explicit risk assessment) for this regionally protected species, as well as providing guidance for future research efforts (e.g., areas of interest for sampling).

An updated checklist of chondrichthyans of Calabria (Central Mediterranean, southern Italy), with emphasis on rare species

In this contribution the checklist of chondrichthyans of Calabria (Central Mediterranean, southern Italy) is reported. Data presented is derived from twenty years of opportunistic and active surveys from 2000 to 2020. A total of 55 species of chondrichthyans is present in Calabrian seas: 33 sharks, 20 rays, and 2 chimaeras. These species represent approximately 62% of the total reported for the Mediterranean. Approximately 71% of Calabrian species have been reported in the Tyrrhenian Sea, 49% in the Ionian Sea, and 33% in the Strait of Messina. According to IUCN criteria, new records of Endangered and Critically Endangered species (i.e., Carcahrodon carcharias [Linnaeus, 1758], Lamna nasus [Bonnaterre, 1788], Cetorhinus maximus [Gunnerus, 1765], Mobula mobular [Bonnaterre, 1788], Sphyrna zygaena [Linnaeus, 1758]) are reported, together with the first record of Raya brachyura Lafont, 1873 for the Ionian coasts and probably third confirmed record of the rare chimaera Hydrolagus mirabilis (Collett, 1904) for the Mediterranean.

A new species of the enigmatic shark genus Nanocetorhinus (Chondrichthyes) from the Oligocene of Austria with palaeoceanographic implications

Deep-neritic sediments of the Eferding Formation (Egerian, Upper Oligocene) of Upper Austria from the Kamig kaolinite quarry revealed minute teeth of the putatively planktivorous shark genus Nanocetorhinus. This is the oldest unambiguous record of this rarely documented genus, which was known so far only from Miocene deposits of Europe, North America and Japan. Based on previous studies, which showed a positive correlation between sediments of nutrient rich waters and plankton blooms with a majority of ichthyoliths of Keasius and Nanocetorhinus, we argue for a filter-feeding and migratory lifestyle of the latter. Thus, it is supposed that Nanocetorhinus migrated seasonally for foraging, in a similar way to the extant basking shark Cetorhinus maximus. This mode of life and the wide paleogeographic distribution of the open marine genus Nanocetorhinus requires a deep and fully marine connection between the Paratethys and the Proto-Mediterranean Sea during late Oligocene times, which might have been established via the Slovenian Corridor.

Assessing the importance of Isle of Man waters for the basking shark Cetorhinus maximus

Satellite tracking of endangered or threatened animals can facilitate informed conservation by revealing priority areas for their protection. Basking sharks Cetorhinus maximus (n = 11) were tagged during the summers of 2013, 2015, 2016 and 2017 in the Isle of Man (IoM; median tracking duration 378 d, range: 89-804 d; median minimum straight-line distance travelled 541 km, range: 170-10406 km). Tracking revealed 3 movement patterns: (1) coastal movements within IoM and Irish waters, (2) summer northward movements to Scotland and (3) international movements to Morocco and Norway. One tagged shark was bycaught and released alive in the Celtic Sea. Basking sharks displayed inter-annual site fidelity to the Irish Sea (n = 3), a Marine Nature Reserve (MNR) in IoM waters (n = 1), and Moroccan waters (n = 1). Core distribution areas (50% kernel density estimation) of 5 satellite tracked sharks in IoM waters were compared with 3902 public sightings between 2005 and 2017, highlighting west and south coast hotspots. Location data gathered from satellite tagging broadly correspond to the current boundaries of MNRs in IoM waters. However, minor modifications of some MNR boundaries would incorporate ~20% more satellite tracking location data from this study, and protective measures for basking sharks in IoM waters could further aid conservation of the species at local, regional and international scales. We also show the first documented movement of a basking shark from the British Isles to Norway, and the longest ever track for a tagged basking shark (2 yr and 2 mo, 804 d).