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, lower planktonic species richness and discolouration of water [7-9]. Even though P. quadridentatum has been reported from different parts of the world, unil now there have been no records of blooms or harmful effects of this species in Indian waters. The study reports the first bloom of P. quadridentatum along the tropical waters of Cochin estuary (Southwest coast of India). Cochin backwater is a productive estuarine system with a high plankton diversity. It is highly influenced by the monsoon run off and inputs from anthropogenic activities which results in a dynamic change in the overall functioning of the system between seasons [10,11]. In November 2018, a sudden discolouration of water was observed near the Marine Science Jetty (Lat. 09o5751N; Long. 76o1656 E) in Cochin estuary (Fig.1). Phytoplankton samples were collected from the bloom area by filtering ~50 liters of surface water through 20μm mesh bolting silk and analysed using a Leica DM2000 microscope. Hydrobiological parameters such as temperature, salinity and dissolved oxygen were measured immediately and dissolved nutrients (nitrate and silicate) were estimated according to standard protocols. Chlorophyll a was measured spectrophotometrically using a Hitachi U-2900 UV/Visible spectrophotometer following the ace tone extraction method. Microscopic examination of samples collected from the bloom event revealed that the discoloration was caused by the dinoflagellate P. quadridentatum (Fig. 2). The cells were solitary, small in size and little longer than wide. The cell was overall ovoid in shape and divided by a cingulum in the middle. The 12 epitheca was conical with pointed apex and the hypotheca was round in shape with four antapical spines, which varied in length. The cells included numerous chloroplasts which were small and somewhat yellow-greenish in colour. A number of P. quadridentatum cells undergoing encystment were also observed (Fig. 2). During the bloom event, the surface chlorophyll a concentration was relatively high (27.5 mg m-3) and P. quadridentatum contributed more than 70% of the overall phytoplankton population with a cell density 6.2 x 104 cells L-1. As well as P. quadridentatum, the dinoflagellate community included Noctiluca scintillans, Tripos muelleri and Protoperidinium sp. Skeletonema costatum and Nitzschia sigma were the dominant diatom species. The P. quadridentatum bloom occurred when physical and chemical conditions during the bloom revealed the surface water temperature was 28oC, salinity 20 psu, and nitrate and silicate concentrations were 10.6 μmol L-1 and 23.3 μmol L-1 respectively. A low dissolved oxygen concentration (2.01 mg L-1) was recorded during the bloom event, but there were no reports of fish mortalities from the bloom area. This observation is the first bloom report of P. quadridentatum along Cochin estuary and further investigation on the bloom dynamics is required. This information will be useful in planning for potential HAB events along Cochin estuary. References 1. Gárate-Lizárraga I & MS MuñetónGómez 2008. Acta Bot Mex 83: 3347 2. Alkawri A et al 2016. Plankton Benthos Res 11: 75-78 3. Okolodkov Y et al 2016. Mar Pollut Bull 108: 289-296 4. Stein FRv 1883. In: VvW Engelmann (eds), II Halfte: Die Naturgesichte der Arthrodelen Flagellaten. Leipzig, pp 130 5. Abé TH 1927. In: Peridiniales. Rep Tôhoku Imper Univer, 4th Ser Biol, Sendai, Japan 2: 383438 6. Hansen G 1995. Phycologia 34: 166170 7. Al-Hashmi K et al 2013. J Fish Aquat Sci 8: 595606 8. Gárate-Lizárraga I & MS MuñetónGómez 2008. Acta Bot Mex 83: 3347 9. de Madariaga I et al 1989. Bot Mar 32: 159-165 10. Menon NN et al 2000. Hydrobiologia 4: 149-183 11. Qasim SZ 2003. Indian Estuaries 259 pp Authors Twinkle Sathish, Lathika Cicily Thomas & Kunnatholickal B Padmakumar, Department of Marine Biology, Microbiology & Biochemistry, School of Marine Sciences, Cochin University of Science and Technology (CUSAT), Kochi-16, Kerala, India Email corresponding author: kbpadmakumar@gmail.com Continued from page 10 been any reports of toxicity associated with Mediterranean strains of A. taylorii [5]. For these reasons, further studies will be planned to better understand the potential risks associated with this microalga and its co-occurrence with other phytoplankton species along the Ligurian coast. Acknowledgements We are grateful to the ARPAL colleagues involved in the bathing water monitoring program and to Susanna Alloisio (ETT S.p.A., Genoa) for her support. This work was funded by EU project @lgaWarning (EuroTransBio-Program ID: ETB2017-028). References 1. Penna A 2002. Mar Ecol 23: 320-328 2. Basterretxea G et al 2005. Estuar Coast Shelf Sci 62 (1-2): 1-12 3. ISPRA, Quaderni - Ricerca Marina n. 5/2012, ISBN 978-88-448-05586. 4. Katsuo et al 2007. Harmful Algae, 6(6), 790-798. 5. Satta et al 2010. Adv Ocean Limn 1(2): 259-269 Authors Valentina Giussani, Fabrizia Colonna & Rosella Bertolotto, Agenzia Regionale per la Protezione dellAmbiente Ligure (ARPAL), Genova, Italy Monica Cangini, Centro Ricerche Marine, Cesenatico (FC), Italy Stefano Accoroni & Cecilia Totti, Dipartimento di Scienze della Vita e dellAmbiente, Università Politecnica delle Marche, Ancona, Italy Mariachiara Chiantore, Department for Earth, Environment and Life Sciences, University of Genoa, Genoa, Italy Silvia Casabianca & Antonella Penna, Department of Biomolecular Sciences, University of Urbino, Urbino, Italy Email corresponding author: valentina.giussani@arpal.liguria.it 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