Ciguatera Fish Poisoning: The Risk from an Aotearoa/New Zealand Perspective

Gambierdiscus and Fukuyoa species have been identified in Aotearoa/New Zealand's coastal waters and G. polynesiensis, a known producer of ciguatoxins, has been isolated from Rangitāhua/Kermadec Islands (a New Zealand territory). The warming of the Tasman Sea and the waters around New Zealand's northern subtropical coastline heighten the risk of Gambierdiscus proliferating in New Zealand. If this occurs, the risk of ciguatera fish poisoning due to consumption of locally caught fish will increase. Research, including the development and testing of sampling methods, molecular assays, and chemical and toxicity tests, will continue. Reliable monitoring strategies are important to manage and mitigate the risk posed by this emerging threat. The research approaches that have been made, many of which will continue, are summarised in this review.

Evidence of cryptic species in the blenniid Cirripectesalboapicalis species complex, with zoogeographic implications for the South Pacific

Rapa Nui, commonly known as Easter Island (Chile), is one of the most isolated tropical islands of the Pacific Ocean. The island location of Rapa Nui makes it the easternmost point of the geographic ranges for many western Pacific fish species that are restricted to the subtropical islands south of 20°S latitude. The blenniid fish species Cirripectesalboapicalis has been thought to have one of the most extensive geographic distribution ranges among these southern subtropical fish species, extending from the southern Great Barrier Reef to Rapa Nui. A phylogenetic analysis was conducted to determine the taxonomic status of the species. The results provide genetic evidence that suggests that this formerly South Pacific-wide species comprises at least three cryptic species with allopatric geographic distributions. The analyses reveal the geographic distributions of these clades and their genetic relationships with each other, and with other species within the genus Cirripectes. The processes that culminated in the current geographic distribution of this species complex and the zoogeographic implications of this finding for the South Pacific region are discussed.

Molecular Identification of Gambierdiscus and Fukuyoa (Dinophyceae) from Environmental Samples

Ciguatera Fish Poisoning (CFP) is increasing across the Pacific and the distribution of the causative dinoflagellates appears to be expanding. Subtle differences in thecal plate morphology are used to distinguish dinoflagellate species, which are difficult to determine using light microscopy. For these reasons we sought to develop a Quantitative PCR assay that would detect all species from both Gambierdiscus and Fukuyoa genera in order to rapidly screen environmental samples for potentially toxic species. Additionally, a specific assay for F. paulensis was developed as this species is of concern in New Zealand coastal waters. Using the assays we analyzed 31 samples from three locations around New Zealand and the Kingdom of Tonga. Fourteen samples in total were positive for Gambierdiscus/Fukuyoa and two samples were also positive using the F. paulensis assay. Samples from the Kermadec Islands were further characterized using high-throughput sequencing metabarcoding. The majority of reads corresponded to Gambierdiscus species with three species identified at all sites (G. australes, G. honu and G. polynesiensis). This is the first confirmed identification of G. polynesiensis, a known ciguatoxin producer, in New Zealand waters. Other known toxin-producing genera were also detected, included Alexandrium, Amphidinium, Azadinium, Dinophysis, Ostreopsis, and Prorocentrum.

New lepidium (brassicaceae) from new zealand

A revision of the New Zealand endemic Lepidium oleraceum and allied species is presented. Sixteen species are recognised, 10 of these are new. The new species are segregated on the basis of morphological characters supported by molecular data obtained from three DNA markers (two rDNA and one cpDNA). One species, Lepidium castellanum sp. nov., is endemic to the Kermadec Islands where it is sympatric with Lepidium oleraceum. The North Island of New Zealand supports four species, with two of them, Lepidium amissum sp. nov. and Lepidium obtusatum, now extinct. The South Island supports six species, that, aside from Lepidium banksii, Lepidium flexicaule and Lepidium oleraceum, are all confined to the south-eastern half of the island (Lepidium aegrum sp. nov., Lepidium crassum sp. nov. and Lepidium juvencum sp. nov.). One of these, Lepidium juvencum sp. nov., extends to Stewart Island. The Chatham Islands support six species (Lepidium flexicaule, Lepidium oblitum sp. nov., Lepidium oleraceum, Lepidium oligodontum sp. nov., Lepidium panniforme sp. nov., and Lepidium rekohuense sp. nov.), one of which, Lepidium oligodontum sp. nov., extends to the Antipodes Islands group. The remote, subantarctic Bounty Islands group supports one endemic, Lepidium seditiosum sp. nov., which is the only vascular plant to be recorded from there. Lepidium limenophylax sp. nov. is known from islands off the south-western side of Stewart Island/Rakiura, The Snares and Auckland islands. Lepidium naufragorum, although not related to Lepidium oleraceum and its allies, is also treated because populations with entire leaves are now known. Typification is undertaken for Lepidium banksii, Lepidium oleraceum, Lepidium oleraceum var. acutidentatum, var. frondosum and var. serrulatum.