Taxonomy and toxicity of Prorocentrum from Perhentian Islands (Malaysia), with a description of a non-toxigenic species Prorocentrum malayense sp. nov. (Dinophyceae)

Abstract

A B S T R A C TThirteen isolates of Prorocentrum species were established from the coral reefs of Perhentian Islands Marine Park, Malaysia and underwent morphological observations and molecular characterization. Six species were found: P. caipirignum, P. concavum, P. cf. emarginatum, P. lima, P. mexicanum and a new morphotype, herein designated as P. malayense sp. nov. Prorocentrum malayense, a species closely related to P. leve, P. cf. foraminosum, P. sp. aff. foraminossum, and P. concavum (Clade A sensu Chomérat et al. 2018), is distinguished from its congeners as having larger thecal pore size and a more deeply excavated V-shaped periflagellar area. Platelet arrangement in the periflagellar area of P. malayense is unique, with the presence of platelet 1a and 1b, platelet 2 being the most anterior platelet, and a broad calabash-shaped platelet 3. The species exhibits consistent genetic sequence divergences for the nuclear-encoded large subunit ribosomal RNA gene (LSU rDNA) and the second internal transcribed spacer (ITS2). The phylogenetic inferences further confirmed that it represents an independent lineage, closely related to species in Clade A sensu Chomérat et al. Pairwise comparison of ITS2 transcripts with its closest relatives revealed the presence of compensatory base changes (CBCs). Toxicity analysis showed detectable levels of okadaic acid in P. lima (1.0-1.6 pg cell ˗1 ) and P. caipirignum (3.1 pg cell ˗1 ); this is the first report of toxigenic P. caipirignum in the Southeast Asian region. Other Prorocentrum species tested, including the new species, however, were below the detection limit.

Morphology and Phylogenetics of Benthic Prorocentrum Species (Dinophyceae) from Tropical Northwestern Australia

“…Our field specimens and culture of P. concavum corresponded to the original description [39] of the species and further observations (e.g., References [13,14,19,39,40,41,42,43,44,45]) (see Supplementary Table S1, for details). Morton [41] described P. faustiae Morton, a species extremely similar to P. concavum , from reef flats near Heron Island, Great Barrier Reef, as broad oval cells 43–49 µm in length and 38–42 µm in width (synonymized with P. concavum by Chomérat et al [13]), while Mohammad-Noor et al [43] reported a range of 43–53 μM in length and 38–48 μM in width for P. concavum (but a larger range for specimens identified as P. cf.…”

“…Among them, species of the genus Prorocentrum C.G.Ehrenberg are recurrently reported from tropical and temperate waters, where they occur in benthic, epibenthic and planktonic habitats [5,12]. Approximately 70 species of Prorocentrum are known, with Prorocentrum micans C.G.Ehrenberg as the type, of which around 30 species are associated with sediments and live epiphytically on macroalgal surfaces, floating detritus and corals [5,12,13,14].…”

First report on okadaic acid production of a benthic dinoflagellate Prorocentrum cf. fukuyoi from Japan

“…emarginatum (MG600148, Lim et al . ), and a Brazilian strain UFBA033 of P. emarginatum (KY912158, Mendes et al . ) did not show detectable contents of DSTs nor pectenotoxin‐2 as determined by the instrumental analysis such as LC/MS/MS analysis.…”

Phylogeography and Diversity Among Populations of the Toxigenic Benthic Dinoflagellate Prorocentrum From Coastal Reef Systems in Mexico

“…Two data sets with 13 species were assembled, one for the LSU locus with 68 sequences, and another for the ITS 1 www.CLCbio.com 2 www.ncbi.nlm.nih.gov/genbank/ locus with 72 sequences (Supplementary Table 1). Taxonomic sampling mainly followed Chomérat et al (2019), with the addition of recently described species in the genus (Luo et al, 2017;Nascimento et al, 2017;Lim et al, 2019). Each data set was analyzed with maximum likelihood and Bayesian inference approach under the same conditions as described below.…”