A New Heterotrophic Dinoflagellate from the North‐eastern Pacific, Protoperidinium fukuyoi: Cyst–Theca Relationship, Phylogeny, Distribution and Ecology

Abstract

The cyst-theca relationship of Protoperidinium fukuyoi n. sp. (Dinoflagellata, Protoperidiniaceae) is established by incubating resting cysts from estuarine sediments off southern Vancouver Island, British Columbia, Canada, and San Pedro Harbor, California, USA. The cysts have a brown-coloured wall, and are characterized by a saphopylic archeopyle comprising three apical plates, the apical pore plate and canal plate; and acuminate processes typically arranged in linear clusters. We elucidate the phylogenetic relationship of P. fukuyoi through large and small subunit (LSU and SSU) rDNA sequences, and also report the SSU of the cyst-defined species Islandinium minutum (Harland & Reid) Head et al. 2001. Molecular phylogenetic analysis by SSU rDNA shows that both species are closely related to Protoperidinium americanum (Gran & Braarud 1935) Balech 1974. Large subunit rDNA phylogeny also supports a close relationship between P. fukuyoi and P. americanum. Three subgroups in total are further characterized within the Monovela group. The cyst of P. fukuyoi shows a wide geographical range along the coastal tropical to temperate areas of the North-east Pacific, its distribution reflecting optimal summer sea-surface temperatures of ~14-18 °C and salinities of 22-34 psu.

Cyst–theca relationship and phylogenetic positions ofProtoperidinium(Peridiniales, Dinophyceae) species of the sectionsConicaandTabulata, with description ofProtoperidinium shanghaiensesp. nov.

“…S1). Molecular phylogenies suggested that most of these sections were monophyletic and were nested within the Protoperidinium sensu stricto clade (Mertens et al 2013). There were only two exceptions: the section Conica was polyphyletic and positioned within the Protoperidinium clade (Yamaguchi et al 2006), and the section Oceanica was monophyletic but positioned outside of the Protoperidinium sensu stricto clade (Sarai et al 2013).…”

“…Protoperidinium and Archaeperidinium with a transitional plate generally have a saphopylic or theropylic 2a archeopyles, respectively (Harland 1982;Ribeiro et al 2010;Mertens et al 2012); whereas, those Protoperidinium species without a transitional plate have a compound archeopyle involving 2 0 -4 0 (Lewis & Dodge 1987;Kawami & Matsuoka 2009;Kawami et al 2009;Mertens et al 2013;Liu et al 2014). Cyst morphology can be diverse and is used to classify cysts within various cyst genera, e.g.…”

Physico-chemical and biological factors influencing dinoflagellate cyst production in the Cariaco Basin

“…Interestingly, higher fluxes of cysts of P. fukuyoi were also recorded in the Santa Barbara Basin under similar circumstances, when a short, secondary upwelling pulse interrupted relaxed upwelling conditions (Bringué et al, 2013). Other sediment trap records of P. fukuyoi cyst production from the Strait of Georgia and Saanich Inlet (Price and Pospelova, 2011) in the productive waters of coastal southwestern Canada also indicate higher fluxes during the warmest months of the year (Mertens et al, 2013). 25…”

“…The dinoflagellate cyst nomenclature follows the paleontological taxonomy system provided in Lentin and Williams (1993) (recently updated in Williams et al, 2017) and conforms to taxonomic descriptions provided by Margalef (1961), Wall and 15 Dale (1966, 1968, 1969, Reid (1977), Matsuoka et al (1990, 2006), Zonneveld (1997, Ellegaard and Moestrup (1999), Head (1996Head ( , 2002, Rochon et al (1999), Zonneveld and Jurkschat (1999), Verleye et al (2011), Mertens et al (2013) and Liu et al (2015), with most cyst description summaries and corresponding motile dinoflagellate names provided in Zonneveld and Pospelova (2015).…”

Islandinium minutum subsp. barbatum subsp. nov. (Dinoflagellata), a New Organic‐Walled Dinoflagellate Cyst from the Western Arctic: Morphology, Phylogenetic Position Based on SSU rDNA and LSU rDNA, and Distribution

“…) and Barrow Strait, Nunavik, Canada (Mertens et al. ). The ITS rDNA was identical for specimens of I. minutum subsp.…”