ever the information presented in publications is not always easy to interpret. Toxic blooms often contain several species and studies on individual species are therefore required to determine the species responsible for the toxin production. In addition, species are sometimes difficult to identify and the species concept in cyanobacteria is a challenge. Nomenclatural Problems There are four specific problems facing the Task Team: Problem 1. The Alexandrium problem Alexandrium is one of the commonest used generic names for toxin-producing HAB dinoflagellate species, but there was initial disagreement about the name to be used for the tamarense group and its allies: Alexandrium Halim, Protogonyaulax F.J.R. Taylor, Gessnerium Halim or Gonyaulax Diesing. An important step was made towards avoiding further confusion at the HAB Conference in Lund, Sweden, in 1988 when the taxonomic expert, Prof. Enrique Balech from Argentina, was invited to discuss and give his opinion on the taxonomy of the group. After a detailed presentation, Balech concluded that all species should be included in the genus Alexandrium Halim. This resulted in heated discussion from/in the audience but objections raised were rejected by Prof. Balech. The chairman of the session, Prof. Karen Steidinger, finally concluded the discussion by asking all persons in the audience to agree on using only Alexandrium in the future. This proposal was adopted and the name Alexandrium has subsequently been used by scientists working on HABs. However in 2019 it was discovered that a species of the poorly known genus Centrodinium nested within the genus Alexandrium in the molecular trees provided by Li et al [1]. Species belonging to both genera formed a monophyletic group. As Centrodinium was described by Kofoid in 1907 [2] but 2 Alexandrium by Halim only in 1960, the old name Centrodinium takes priority if the two genera are to be merged. As changes of well-known names are a source of confusion, the botanical code establishes that well-known names of particular importance may be conserved: Conservation aims at retention of those names that best serve stability of nomenclature (International Code of Nomenclature for Algae, Fungi and Plants 2018, Art. 14, 2). The case of Alexandrium versus Centrodinium is such a case. A formal proposal to conserve the name Alexandrium instead of Centrodinium is now being prepared to be submitted to the General Committee of the International Code of Nomenclature for Algae, Fungi and Plants. Subsequently splitting of Alexandrium was suggested [3]. An article containing arguments against this move has been submitted by Mertens et al. (pers. comm.). Until the problems have been settled, the IOC List of Harmful Algae will continue to use the name Alexandrium in the context of the 1988 decision. Problem 2. The Cochlodinium polykrikoides problem One of the most harmful fish killers has been referred to as Cochlodinium polykrikoides since its description from Puerto Rico in 1961. Huge fish kills have occurred in East Asia as a result of blooms of this species and South Korea has been particularly badly impacted. The species name was recently changed to Margalefidinium polykrikoides (Margalef) F. Gómez, Richlen & Anderson 2017 [4]. To change the name of wellknown species always causes confusion and misunderstandings, and the problem in this case is as follows. A genus is nomenclaturally anchored to its type species and the type species of Cochlodinium is Cochlodinium strangulatum (F. Schütt) F. Schütt 1896. Like many other unarmoured (naked) dinoflagellates, Cochlodinium is and has always been a heterogenous genus. It comprises both chloroplast-containing and chloroplast-lacking species, and molecular data have shown, not surprisingly, that the chloroplast-containing species Cochlodinium polykrikoides Margalef is not closely related to the heterotrophic, chloroplast-lacking type species C. strangulatum. They should therefore not be retained in the same genus, and the transfer of C. polykrikoides to the new genus Margalefidinium is a logical proposal. Due to the economic importance of this species, conservation of the name Cochlodinium polykrikoides would cause much less confusion. Conservation can be attained by formally proposing to the General Committee of the International Code of Nomenclature for Algae, Fungi and Plants that the genus Cochlodinium be conserved with C. polykrikoides as type species, to replace C. strangulatum. A proposal to that effect is now being prepared and, if accepted, will conserve the name Cochlodinium polykrikoides. The species C. strangulatum will then need to be given a new generic name but given the fact that it is a little-known species, a new generic name for this species will cause little confusion. A species from the Far East related to Cochlodinium polykrikoides is Cochlodinium catenatum Okamura described from Tokyo Bay [5]. If the proposal to conserve the genus Cochlodinium with Cochlodinium polykrikoides as type is accepted, C. catenatum will again be the correct name of that species. Problem 3. Prorocentrum rhathymum and P. mexicanum Gómez et al [4] have recently claimed that the species Prorocentrum rhathymum Osorio-Tafall and P. mexicanum A.R. Loeblich, Sherley & R.J. Schmidt are synonyms. The question of possible synonymy goes back to Steidinger in 1983 [6] who claimed, four years after P. mexicanum was described by Loeblich et al [7], that the two taxa were synonyms. Faust [8] went on to state, incorrectly, that Loeblich et al, when describing the new species P. rhathymum, HARMFUL ALGAE NEWS NO. 64 / 2020 Harmful Algae News An IOC Newsletter on Toxic Algae and Algal Blooms No. 64 - June 2020 www.ioc-unesco.org/hab The IOC Taxonomic Reference List of Harmful Microalgae The creation of the IOC Taxonomic Reference List of Harmful Microalgae was first discussed 23 years ago at the Fourth Session of the ever the information presented in publications is not always easy to interpret. Toxic blooms often contain several species and studies on individual species are therefore required to determine the species responsible for the toxin production. In addition, species are sometimes difficult to identify considered this to be identical to the previously described P. mexicanum [9]. This statement makes little sense, and Loeblich et al in fact do not mention P. mexicanum in their article. Faust [8] illustrated material which resembled P. rhathymum using the radical arrangement of some of the trichocys Massive salmon mortalities during a Chrysochromulina leadbeateri bloom in Northern Norway From mid May to mid June 2019, fish farmers along the coast of Nordland and Troms, northern Norway, experienced sudden mortalities of caged salmon [1] (Fig. 1). These mortalities were assumed to be due to a blo Fish kill in numbers [2] 13 000 ton fish 7.5 mill salmon 80 mill EUR 14 companies Fig. 2. Map of Norway showing the area where the Chrysochromulina leadbeateri bloom occurred causing massive fish kills in May-June 2019 References 1. Fiskeridirektoratet 2019. https:// www.fiskeridir.no/Akvakult Mass mortality of marine invertebrates associated with the presence of yessotoxins in northern Chile Fig. 1. Map of the study area showing A) Chilean coast; B) Pabellón de Pica, Tarapacá Region C) Bahía Inglesa, Atacama Region; D) Puerto Aldea, Coquimbo Region During the austral summer of 2019, ma research is needed to determine the mechanism of action and the toxin effects on tissues and cells of the main affected species. Finally, there is a need to establish an educational plan to protect the public and avoid the consumption and commercialization of potentially toxic marine invertebrates. First Report of Heterocapsa minima (Dinophyceae) from Aotearoa/ New Zealand Small planktonic armoured dinoflagellates within the genus Heterocapsa are currently represented by 20 species with some having a world-wide distribution [1-2]. Blooms of some Heterocapsa species have been associated with fi Fig. 2. Maximum likelihood (ML) molecular phylogenetic tree of Heterocapsa minima and H. steinii strains isolated from coastal areas of New Zealand based on the LSU rDNA D1/ D2 sequences (20 sequences, 700 positions). The alignment site corresponded to the 69768 bp site of a sequence from H. steinii Yellow-green tides could become a recurrent event along the Ligurian coast (Italy) Fig. 1. A) Sestri Levante and Baia del Silenzio bay, characterized by shallow water and mixed rocky-sandy seabed containing the macrophyte, Posidonia oceanica (dark grey) and carpet-like matte (light grey) habitat. B First report of a high biomass bloom of Peridinium quadridentatum (F. Stein) Gert Hansen from the tropical Cochin estuary SW coast of India Fig. 1. Map showing the area of P. quadridentatum bloom in Cochin estuary, southwest coast of India Peridinium quadridentatum (F. Stein) Gert Hansen is a cos Table 1. Physico-chemical parameters of P. quadridentatum bloom area in Cochin Estuary Parameters Water Temperature (oC) Salinity (psu) Dissolved Oxygen (ml L-1) Nitrate (μmol L-1) Silicate (μmol L-1) Phosphate (μmol L-1) Chlorophyll a (mg m-3) 28 20 2.01 10.6 23.3 1.3 27.5 higher turbidity, lowe Are mesophotic seamounts reservoirs for potentially toxic dinoflagellates associated with Ciguatera poisoning? A case study from the SW Indian ocean (expédition La Pérouse, 2019) Fig. 1. Location map of La Pérouse seamount off La Réunion. In the western Indian Ocean, a Ciguatera Fish Poisoning (CF Using Machine Learning to Observe Abundance Patterns of the Dino flagellate Noctiluca scintillans in the Western English Channel Noctiluca scintillans is a Harmful Algal Bloom (HAB) species with a wide geographic distribution. It frequently blooms and causes negative impacts on marine ecosystems [1] References 1. Sarma VVSS et al 2019. Mar Pollut Bull 138: 428-436 2. Faust MA & RA Gulledge 2002. Contributions for the US National Herbarium 42: 1-144 3. Graham MD et al 2018. Limnol Oceanogr-Meth 16: 669-679 Author Christian Bamber, The Marine Biological Association, Citadel Hill, Plymouth PL1 2PB International validation and recognition of method for paralytic shellfish toxins in bivalve molluscs Food safety scientists from Cefas (UK) and Cawthron Institute (New Zealand) have led an international study over the past four years to gain international recognition for a new method to quantify pa Aotearoa/New Zealands nationally significant Cawthron Institute Culture Collection of Microalgae (CICCM) The CICCM is critical to international research projects and the 500 isolates of microalgae and cyanobacteria in the collection have been sourced from oceans, lakes and rivers in New Zealand, the The 11th EASTHAB Symposium and 4th Philippine HAB Conference The 11th EASTHAB Symposium and 4th Philippine HAB Conference were held back-to-back from December 11 13, 2019 at the Microtel Hotel, Puerto Princesa, Palawan, the Philippines. The theme was Advances in Harmful Algal Bloom Research, Monito Fig. 1. Participants in the 11th EASTHAB Symposium/4th Philippine HAB Conference Fig. 2. Department of Science and Technology secretary Fortunato dela Peña with the keynote, plenary speakers and local organizing committee leads. Left to right: Dr. Ichiro Imai, representative of the Vice Mayor of Pu The ICES-IOC Working Group on Harmful Algal Bloom Dynamics 2020 Meeting The International Council for the Exploration of the Sea (ICES) and the Intergovernmental Oceanographic Commission of UNESCO (IOC) have collaborated closely for 26 years, stimulating research on HAB population dynamics and monit Fig. 2. Shared day between ICES-IOC WGHABD, ICES-IOC WGBOSV and ICES WGITMO ences using molecular methods as well as results from studies in Arctic areas. These studies presented data on HAB and invasive non-native species present in Arctic waters. A USA study focused on the distribution, community Typical benthic habitat with macroalgae and limestone rubble observed at ~ 60m depth on La Pérouse seamount, Indian Ocean (Photo courtesy of L. Ballesta). Eds-in-chief Beatriz Reguera, IEO, Vigo, Spain Eilen Bresnan, Marine Scotland, UK Regional Editors Caribbean: Ernesto Mancera jemancerap@unal.e