TY - JOUR T1 - The cyst-theca relationship of the dinoflagellate cyst Trinovantedinium pallidifulvum, with erection of Protoperidinium lousianensis sp nov and their phylogenetic position within the Conica group A1 - Mertens,Kenneth A1 - Gu,Haifeng A1 - Takano,Yoshihito A1 - Price,Andrea M. A1 - Pospelova,Vera A1 - Bogus,Kara A1 - Versteegh,Gerard J. M. A1 - Marret,Fabienne A1 - Turner,R. Eugene A1 - Rabalais,Nancy N. A1 - Matsuoka,Kazumi AD - Univ Ghent, Res Unit Palaeontol, Krijgslaan 281 S8, B-9000 Ghent, Belgium. AD - SOA, Inst Oceanog 3, Xiamen 361005, Peoples R China. AD - Inst East China Sea Res ECSER, 1551-7 Taira Machi, Nagasaki 8512213, Japan. AD - McGill Univ, Dept Geog, Burnside Hall,805 Sherbrooke St West, Montreal, PQ H3A OB9, Canada. AD - Univ Victoria, Sch Earth & Ocean Sci, OEASB A405,POB 1700 STN CSC, Victoria, BC V8W 2Y2, Canada. AD - Texas A&M Univ, Int Ocean Discovery Program, 1000 Discovery Dr, College Stn, TX 77845 USA. AD - MARUM Ctr Marine Environm Sci, Leobener Str, D-28359 Bremen, Germany. AD - Univ Liverpool, Sch Environm Sci, Liverpool L69 7ZT, Merseyside, England. AD - Louisiana State Univ, Dept Oceanog & Coastal Sci, Baton Rouge, LA 70803 USA. AD - Louisiana Univ Marine Consortium, Chauvin, LA 70344 USA. UR - https://doi.org/10.1080/01916122.2016.1147219 DO - 10.1080/01916122.2016.1147219 KW - Micro-FTIR KW - Selenopemphix undulata KW - Wadden Sea KW - Lake Saroma KW - Saanich Inlet KW - Gulf of Mexico N2 - We establish the cyst-theca relationship of the dinoflagellate cyst species Trinovantedinium pallidifulvum Matsuoka 1987 based on germination experiments of specimens isolated from the Gulf of Mexico. We show that the motile stage is a new species, designated as Protoperidinium louisianensis. We also determine its phylogenetic position based on single-cell polymerase chain reaction (PCR) of a single cell germinated from the Gulf of Mexico cysts. To further refine the phylogeny, we determined the large subunit (LSU) sequence through single-cell PCR of the cyst Selenopemphix undulata isolated from Brentwood Bay (Saanich Inlet, BC, Canada). The phylogeny shows that P. louisianensis is closest to P. shanghaiense, the motile stage of T. applanatum, and is consistent with the monophyly of the genus Trinovantedinium. Selenopemphix undulata belongs to a different clade than Selenopemphix quanta (alleged cyst of P. conicum), suggesting that the genus Selenopemphix is polyphyletic. Trinovantedinium pallidifulvum is widely distributed with occurrences in the Gulf of Mexico, the North Atlantic, the northeast Pacific and southeast Asia. In addition, we illustrate the two other extant species, Trinovantedinium applanatum and Trinovantedinium variabile, and two morphotypes of Trinovantedinium. Geochemical analyses of the cyst wall of T. pallidifulvum indicate the presence of amide groups in agreement with other heterotrophic dinoflagellate species, although the cyst wall of T. pallidifulvum also includes some unique features. Y1 - 2017 PB - Taylor & Francis Inc JF - Palynology SN - 0191-6122 VL - 41 IS - 2 SP - 183 EP - 202 ID - 49609 ER -