@article{c4bf82c63a2f410e972514cc2ecdd196,
title = "Significance of the Nudiform and Tectiform Modes of Silica Deposition, Lorica Assembly and Cell Division in Choanoflagellates as Exemplified by Stephanoeca diplocostata and Enibas spp.",
abstract = "The deposition of silicified costal strips and lorica assembly in choanoflagellates is precisely linked to the cell cycle. A minority of species undergo nudiform division whereby a loricate cell divides to produce a naked daughter cell that deposits a set of costal strips and then assembles a lorica. Most species undergo tectiform division whereby a parent loricate cell produces a set of costal strips, divides and passes on the stored strips to a daughter cell that immediately assembles a lorica. Many phylogenetic analyses recover nudiform and tectiform species as sister-clades giving the impression that they are distinct evolutionary lineages. However, the tectiform species Stephanoeca diplocostata is capable of undergoing nudiform division and depositing costal strips and assembling a lorica with certain modifications in a nudiform manner. The recent discovery of a new genus, Enibas, comprising species with Stephanoeca-like loricae that undergo nudiform cell division and on phylogenetic analysis occur as a sister group to other nudiform species has drawn attention to whether there are also unique features in lorica construction. A range of Enibas loricae is illustrated and it appears that there are unique features which might be interpreted as being derived from a Stephanoeca-like ancestor.",
keywords = "Acanthoecida, Choanoflagellatea, Stephanoeca diplocostata, nudiform-tectiform relationship, Enibas lorica morphology, Enibas evolution",
author = "Leadbeater, {Barry S.c.} and Martin Carr",
note = "Funding Information: This manuscript is dedicated in memoriam of Professor Bland Finlay FRS who throughout his research career made an outstanding contribution to ecological protistology. We are thankful for the assistance of Carol Morton, Peter Whittle and Steve Price for help with the electron microscopy. John van den Hoff kindly made available high-quality images of Stephanoeca complexa and S. norrisii. Professor Yves Le Gal hosted the visit of BSCL to the Concarneau Marine Laboratory in 1976. Malcolm Davies† designed and built the apparatus used for the silicon experiments. The authors much appreciate the constructive comments of two anonymous reviewers. We are grateful to Cambridge University Press for permission to reproduce Figures 3–6, 13, 14, 20, 21 and 31 which were previously published in Leadbeater ((2015) – The Choanoflagellates: Evolution, Biology and Ecology. Cambridge University Press). The authors declare that they have no known financial or intellectual conflict of interest that could have influenced the work reported in this paper. This research did not receive any specific grant: 1 from funding agencies in the public; 2 commercial, or not-for-profit sectors. Barry Leadbeater: Conceptualization, Specimen Collection, Electron Microscopy, Writing - Original Draft. Martin Carr: Conceptualization, Methodology, Formal analysis, Writing - Original Draft. Publisher Copyright: {\textcopyright} 2022 Elsevier GmbH",
year = "2022",
month = dec,
day = "1",
doi = "10.1016/j.protis.2022.125923",
language = "English",
volume = "173",
journal = "Protist",
issn = "1434-4610",
publisher = "Urban und Fischer Verlag Jena",
number = "6",
}
