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9. Highly divergent morphology but a close molecular phylogenetic relationship between two little‐known ciliate genera Actinobolina and Papillorhabdos (Protozoa: Ciliophora: Litostomatea) with description of two new species.

Author

Chi, Yong, Tang, Danxu, Lei, Jingtao, Wei, Fan, Al‐Farraj, Saleh A., Bourland, William A., and Chen, Zigui

Subjects
CILIATA, MORPHOLOGY, NUTRIENT cycles, SPECIES, MARINE habitats, FRESHWATER habitats
Abstract

Free‐living litostomatean ciliates, prominent microeukaryote predators commonly encountered in freshwater and marine habitats, play vital roles in maintaining energy flow and nutrient cycles. Nevertheless, understanding their biodiversity and phylogenetic relationships remains challenging due to insufficient morphological information and molecular data. As a new contribution to this group, three haptorian ciliates, including two new species (Actinobolina bivacuolata sp. nov. and Papillorhabdos foissneri sp. nov.) and the insufficiently described type species, Actinobolina radians, were isolated from wetlands around Lake Weishan, China and investigated by a combination of living morphology, stained preparations, and 18S rRNA gene sequence data. An illustrated key of the valid species within the two genera is provided. In addition, we reveal the phylogenetic positions of these two genera for the first time. Although they differ in all key morphologic characters such as general appearance (ellipsoidal with numerous tentacles vs. cylindrical), extrusomes (stored in tentacles vs. anchored to pellicle), circumoral kinety (present vs. absent), composition of somatic kineties (kinetosome clusters vs. monokinetids), and number of dorsal brush rows (1 vs. 4), they both cluster in a fully supported clade in the phylogenetic tree, which indicates that the biodiversity and additional molecular markers of this group need further exploration. [ABSTRACT FROM AUTHOR]

Published
2024
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18. Ciliates — Protists with complex morphologies and ambiguous early fossil record

Author

Dunthorn, Micah, Lipps, Jere H., Dolan, John R., Saab, Marie Abboud-Abi, Aescht, Erna, Bachy, Charles, de Cao, María Sonia Barría, Berger, Helmut, Bourland, William A., Choi, Joong Ki, Clamp, John, Doherty, Mary, Gao, Feng, Gentekaki, Eleni, Gong, Jun, Hu, Xiaozhong, Huang, Jie, Kamiyama, Takashi, Johnson, Matthew D., Kammerlander, Barbara, Kim, Sun Young, Kim, Young-Ok, la Terza, Antonietta, Laval-Peuto, Michèle, Lipscomb, Diana, Lobban, Christopher S., Long, Hongan, Luporini, Pierangelo, Lynn, Denis H., Macek, Miroslav, Mansergh, Robert I., Martín-Cereceda, Mercedes, McManus, George G., Montagnes, David J.S., Ong'ondo, Geoffrey O., Patterson, David J., Pérez-Uz, Blanca, Quintela-Alonso, Pablo, Safi, Lúcia S.L., Santoferrara, Luciana F., Sonntag, Bettina, Song, Weibo, Stoeck, Thorsten, Stoecker, Diane K., Strüder-Kypke, Michaela C., Trautmann, Isabelle, Utz, Laura R.P., Vallesi, Adriana, Vd'ačný, Peter, Warren, Alan, Weisse, Thomas, Wickham, Stephen A., Yi, Zhenzhen, Zhang, Wuchang, Zhan, Zifeng, Zufall, Rebecca, and Agatha, Sabine

Published
2015
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28. Hypotrichidium tisiae(Gelei, 1929) Gelei, 1954: a unique hypotrichid ciliate having a highly specialized developmental pattern during binary division

Author

Luo, Xiaotian, Huang, Jie, Ma, Honggang, Liu, Yujie, Lu, Xiaoteng, and Bourland, William A.

Abstract

In sharp contrast to their pelagic relatives, the oligotrichs, the overwhelming majority of hypotrich ciliates inhabit the benthos. Only a few species, including those of the genus HypotrichidiumIlowaisky, 1921, have adapted to a planktonic lifestyle. The ontogenetic mode of the highly differentiated ciliate, Hypotrichidium tisiae(Gelei, 1929) Gelei, 1954, is unknown. In this study, the interphase morphology and the ontogenetic process of this species are investigated. Accordingly, the previously unidentified ciliary pattern of Hypotrichidiumis redefined. The main morphogenetic features are as follows: (1) The parental adoral zone of membranelles is inherited completely by the proter and the oral primordium of the opisthe arises in a deep pouch. (2) Five frontoventral cirral anlagen (FVA) are formed: FVA I contributes to the single frontal cirrus, FVA II–IV generate three frontoventral cirral rows, FVA V migrates and forms postoral ventral cirri. (3) All marginal cirral row anlagen develop de novo: each of the two left anlagen forms a single cirral row, while the single right anlage fragments into anterior and posterior parts. (4) Two dorsal kinety anlagen occur de novo, with the right one fragmenting to form kineties 2 and 3. (5) Two long caudal cirral rows are formed at the ends of dorsal kineties 1 and 3. On the basis of the morphogenetic features and phylogenetic analyses, the assignment of Hypotrichidiumto the family Spirofilidae Gelei, 1929 within Postoralida is supported. The establishment of separate families for the slender “tubicolous” spirofilids and the highly helical spirofilids is also validated.

Published
2022
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29. Morphology and phylogeny of two anaerobic freshwater ciliates: Brachonella comma sp. nov. and the widely distributed but little‐known caenomorphid, Ludio parvulus Penard, 1922.

Author

Bourland, William, Pomahač, Ondřej, and Čepička, Ivan

Subjects
*CILIATA, *PHYLOGENY, *FRESH water, *MORPHOLOGY, *PROTISTA
Abstract

Hypoxic, sulfidic freshwater sediments typically support a diffuse consortium of distinctive ciliated protists, including caenomorphids, metopids, and odontostomatids among others. A recent resurgence of interest in these important members of sapropelic food webs has resulted in the description of many new species and an effort, still in its infancy, to characterize them from a morphologic, molecular, and metabolic standpoint and to determine their phylogenetic relationships. Their seemingly invariable association with prokaryotic endosymbionts and, less commonly, ectosymbionts has become a focus for many researchers. In this report, based on morphologic and molecular data, we describe a Brachonella species (Ciliophora, Metopida) new to science and analyze its phylogeny. We also provide a morphologic and molecular characterization of the smallest representative of the Caenomorphidae Poche, 1913, Ludio parvulus Penard, 1922. The phylogenetic analysis confirms the inclusion of this species in the Caenomorphidae. [ABSTRACT FROM AUTHOR]

Published
2022
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39. Some morphologically distinguishable hypotrich ciliates share identical 18S rRNA gene sequences – taxonomic insights from a case study on Oxytricha species (Protista, Ciliophora).

Author

Fan, Xinpeng, Yao, Shunli, Luo, Xiaotian, Dong, Tianyao, Xu, Yuan, Chen, Lingyun, Bourland, William, Zhao, Yan, and Huang, Jie

Subjects
CYTOCHROME oxidase, CILIATA, RIBOSOMAL RNA, PROTISTA, SPECIES, GENES, ELECTRON microscopy
Abstract

Modern taxonomic studies of ciliated protozoa require both morphological and molecular data. One dilemma is how to distinguish morphologically similar species with few nucleotide differences in the widely used marker, the 18S rRNA gene. In the present study, two Oxytricha species were morphologically documented using light and electron microscopy. The mitochondrial cytochrome c oxidase subunit I (COI) gene and a fragment of the rRNA gene covering the 18S-ITS1-5.8S-ITS2-28S rRNA gene regions were sequenced. Phylogenetic analyses of all available Oxytricha granulifera -related populations were performed to reveal the internal relationships of this group. We described a new species, Oxytricha atypica sp. nov. , distinguished from its congeners by having seven postoral ventral cirri resulting from the additional fragmentation of anlage V during ontogenesis. Although their 18S rRNA genes differ by only one nucleotide, divergence of the COI gene is as high as 11.8% between O. atypica and the closely related species, O. granulifera. All but one of the COI nucleotide substitutions were synonymous. We documented the highly conserved nature of the 18S rRNA gene in the morphospecies of Oxytricha. Based on these findings, we speculate that O. granulifera contains cryptic species or morphospecies needing further characterization, and new insights for the taxonomy of hypotrich ciliates are also discussed. [ABSTRACT FROM AUTHOR]

Published
2021
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43. Morphology, Morphogenesis, and Phylogeny of Urosoma caudata (Ehrenberg, 1833) Berger, 1999 (Ciliophora, Hypotrichia) based on a Chinese Population.

Author

Xu, Wenxin, Zhao, Yan, Pan, Bo, Liu, Yongqiang, Li, Yuan, Bourland, William A., and Luo, Xiaotian

Subjects
SALAMANDERS, PHYLOGENY, MORPHOLOGY, CILIATA, RIBOSOMAL RNA, SPECIES, MOLECULAR phylogeny, MORPHOGENESIS
Abstract

We report the morphology and morphogenesis of Urosoma caudata (Ehrenberg, 1833) Berger, 1999 based on in vivo observation and protargol impregnation and provide an improved diagnosis of U. caudata based on previous and current work. Urosoma caudata differs from its congeners mainly by the combination of the following features: tail‐like posterior end, colorless cortical granules, and two macronuclear nodules. Urosoma caudata shares most of the ontogenetic features with its congeners: the oral primordium of the opisthe develops apokinetally, and the frontal‐ventral‐transverse cirral anlagen develop in five streaks. However, a unique morphogenetic characteristic is recognizable: the anlagen of three dorsal kineties occur de novo to the left of the parental structures differing from their intrakinetal origin in other Urosoma species. The first record of the 18S rRNA gene sequence for the species is also provided. Phylogenetic analyses based on 18S rRNA gene sequence data suggest that the genus Urosoma is a nonmonophyletic group. [ABSTRACT FROM AUTHOR]

Published
2020
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50. Remodeling the Specificity of an Endosomal CORVET Tether Underlies Formation of Regulated Secretory Vesicles in the Ciliate Tetrahymena thermophila

Author

Sparvoli, Daniela, primary, Richardson, Elisabeth, additional, Osakada, Hiroko, additional, Lan, Xun, additional, Iwamoto, Masaaki, additional, Bowman, Grant R., additional, Kontur, Cassandra, additional, Bourland, William A., additional, Lynn, Denis H., additional, Pritchard, Jonathan K., additional, Haraguchi, Tokuko, additional, Dacks, Joel B., additional, and Turkewitz, Aaron P., additional

Published
2018
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