FN Archimer Export Format PT J TI The affiliation of Hexasterias problematica and Halodinium verrucatum sp. nov. to ciliate cysts based on molecular phylogeny and cyst wall composition BT AF GURDEBEKE, Pieter R. MERTENS, Kenneth TAKANO, Yoshihito YAMAGUCHI, Aika BOGUS, Kara DUNTHORN, Micah MATSUOKA, Kazumi VRIELINCK, Henk LOUWYE, Stephen AS 1:1;2:2;3:3;4:4;5:5,6;6:7;7:3;8:8;9:1; FF 1:;2:PDG-ODE-LITTORAL-LERBO;3:;4:;5:;6:;7:;8:;9:; C1 Univ Ghent, Dept Geol, Krijgslaan 281, B-9000 Ghent, Belgium. Ifremer, Stn Biol Marine, LER BO, Pl Croix,BP40537, F-29185 Concarneau, France. Inst East China Sea Res ECSER, 1-14 Bunkyo Machi, Nagasaki 8528521, Japan. Kobe Univ, Res Ctr Inland Seas, Kobe, Hyogo 6578501, Japan. Univ Nottingham, Sch Geog, Ctr Environm Geochem, Nottingham NG7 2RD, England. Texas A&M Univ, Int Ocean Discovery Program, College Stn, TX 77845 USA. Univ Kaiserslautern, Dept Ecol, Erwin Schrodinger St, D-67663 Kaiserslautern, Germany. Univ Ghent, Dept Solid State Sci, Krijgslaan 281,S1, B-9000 Ghent, Belgium. C2 UNIV GHENT, BELGIUM IFREMER, FRANCE ECSER, JAPAN UNIV KOBE, JAPAN UNIV NOTTINGHAM, UK UNIV TEXAS A&M, USA UNIV KAISERSLAUTERN, GERMANY UNIV GHENT, BELGIUM SI BREST CONCARNEAU SE PDG-ODE-LITTORAL-LERBO IN WOS Ifremer jusqu'en 2018 copubli-europe copubli-int-hors-europe IF 2.626 TC 21 UR https://archimer.ifremer.fr/doc/00468/57970/64186.pdf LA English DT Article DE ;Acritarch;Ciliate cyst;FTIR;LSU-SSU rDNA;Prostomatida;Taxonomy AB Species in the genera Hexasterias and Halodinium have been recorded over the last decades as acritarchs in palynological and/or plankton studies. In paleoenvironmental studies, these resting stages are often interpreted as indicators of freshwater input. The biological affinity of these genera has never been definitely established. Here, a new species, Halodinium verrucatum sp. nov., is described and molecular evidence (single specimen SSU and LSU rDNA sequencing) reveals that both this new species and Hexasterias problematica, collected from sediment samples in the Skagerrak and Baltic Sea, are resting stages of prorodontid ciliates. Additionally, infrared spectroscopic analysis (micro-FTIR) of Hexasterias problematica and Halodinium spp. specimens indicates a carbohydrate-based composition of the cyst wall with evidence for nitrogen-containing functional groups. A similar composition is recorded for tintinnid loricae, which further supports the placement of Hexasterias and Halodinium as ciliate cysts, and the composition is consistent with the heterotrophic nature of ciliates. The morphologically similar species Radiosperma corbiferum has a comparable composition, suggesting a similar ciliate affinity and indicating the utility of micro-FTIR in understanding acritarch affinity. Hexasterias problematica typically occurs in coastal waters from temperate to arctic regions. Halodinium verrucatum sp. nov. is observed in temperate estuarine sediments in the northern hemisphere. PY 2018 PD OCT SO European Journal Of Protistology SN 0932-4739 PU Elsevier Gmbh, Urban & Fischer Verlag VL 66 UT 000452347600012 BP 115 EP 135 DI 10.1016/j.ejop.2018.09.002 ID 57970 ER EF