European journal of protistology最新文献

Not a Lycogala? Investigating the holotype of Lycogala fuscoviolaceum 不是Lycogala？紫石蒜的全型研究

IF 1.9 2区生物学

European journal of protistology Pub Date : 2025-05-08 DOI: 10.1016/j.ejop.2025.126151

Dmytro Leontyev , Martin Schnittler

{"title":"Not a Lycogala? Investigating the holotype of Lycogala fuscoviolaceum","authors":"Dmytro Leontyev , Martin Schnittler","doi":"10.1016/j.ejop.2025.126151","DOIUrl":"10.1016/j.ejop.2025.126151","url":null,"abstract":"<div><div>The myxomycete <em>Lycogala fuscoviolaceum</em> was described by P. Onsberg in 1972 based on a single specimen collected in Nepal. The status of this species remains ambiguous, as no additional findings have been reported since its description. In this study, we re-examined the holotype stored in Copenhagen to determine the true systematic position of <em>L. fuscoviolaceum</em>. Morphological observations revealed features inconsistent with <em>Lycogala</em>, including the dense, cartilaginous cortex, the pseudocapillitium forming vertical bundles, and the thick-walled spores with elongated pore. These characteristics suggest that <em>L. fuscoviolaceum</em> is either a member of the family Reticulariaceae, possibly related to <em>Reticularia</em> or <em>Siphoptychium</em>, or it is not a myxomycete at all. Cross-sections of the cortical structures of <em>L. fuscoviolaceum</em> revealed the presence of cell-like elements arranged in distinct layers. Such elements were absent in <em>Reticularia splendens</em>, <em>Siphoptychium reticulatum</em>, and <em>S. violaceum</em>, but present in <em>L. flavofuscum</em>. Attempts to obtain molecular data from the holotype of <em>L. fuscoviolaceum</em>, including high-throughput sequencing of short fragments, were unsuccessful due to DNA degradation. New findings are required to clarify the taxonomic position of the species.</div></div>","PeriodicalId":12042,"journal":{"name":"European journal of protistology","volume":"99 ","pages":"Article 126151"},"PeriodicalIF":1.9,"publicationDate":"2025-05-08","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"143936446","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":2,"RegionCategory":"生物学","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

引用次数: 0

The athecate dinoflagellate genus Karlodinium (Kareniaceae: Dinophyceae) from Mexican coastal waters, with three new records for the eastern Pacific Ocean 墨西哥沿海的甲藻鞭毛属甲藻属（甲藻科：甲藻科），在东太平洋有三个新记录

IF 1.9 2区生物学

European journal of protistology Pub Date : 2025-04-15 DOI: 10.1016/j.ejop.2025.126150

Jovanny Arana-Garcia , Alexis Escarcega-Bata , David U. Hernández-Becerril , María Eugenia Zamudio-Resendiz

{"title":"The athecate dinoflagellate genus Karlodinium (Kareniaceae: Dinophyceae) from Mexican coastal waters, with three new records for the eastern Pacific Ocean","authors":"Jovanny Arana-Garcia , Alexis Escarcega-Bata , David U. Hernández-Becerril , María Eugenia Zamudio-Resendiz","doi":"10.1016/j.ejop.2025.126150","DOIUrl":"10.1016/j.ejop.2025.126150","url":null,"abstract":"<div><div>The athecate dinoflagellate genus <em>Karlodinium</em> (family Kareniaceae) has a relatively high diversity and is known for its potential ichthyotoxicity in coastal marine environments. In this study, we report the occurrence of four species of <em>Karlodinium</em> in the Mexican Pacific: <em>K. azanzae</em>, <em>K.</em> cf. <em>elegans</em>, <em>K. decipiens</em>, and <em>K. zhouanum</em>. Three species (<em>K. azanzae</em>, <em>K. decipiens</em>, and <em>K. zhouanum</em>) were isolated from Acapulco Bay in March 2023, and one species (<em>K.</em> cf. <em>elegans</em>) was detected in fixed samples collected from the western coasts of Baja California in September 2020. The cell morphology was studied mainly by light microscopy and only <em>K.</em> cf. <em>elegans</em> was examined by scanning electron microscopy. Relevant morphological characters of all studied species were consistent with previous descriptions, and their morphological identification was confirmed by phylogenetic analysis of large subunit (LSU) rDNA sequences. The synonymy of <em>K</em>. <em>jejuense</em> and <em>K</em>. <em>zhouanum</em> was proposed based on a combination of morphological and molecular data.</div></div>","PeriodicalId":12042,"journal":{"name":"European journal of protistology","volume":"99 ","pages":"Article 126150"},"PeriodicalIF":1.9,"publicationDate":"2025-04-15","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"143895024","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":2,"RegionCategory":"生物学","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

引用次数: 0

First contours of autecology of freshwater heterotrophic euglenoids – results of two-year research on 18 freshwater bodies 淡水异养拟绿藻技术的初步轮廓——对18个淡水水体为期两年的研究结果

IF 1.9 2区生物学

European journal of protistology Pub Date : 2025-04-11 DOI: 10.1016/j.ejop.2025.126149

Jaroslav Kubín , Josef Juráň

{"title":"First contours of autecology of freshwater heterotrophic euglenoids – results of two-year research on 18 freshwater bodies","authors":"Jaroslav Kubín , Josef Juráň","doi":"10.1016/j.ejop.2025.126149","DOIUrl":"10.1016/j.ejop.2025.126149","url":null,"abstract":"<div><div>This study brings the first information about the autecological traits of heterotrophic euglenoids at eighteen localities in South Bohemia (Czech Republic). A number of environmental and landscape parameters including water chemistry and diversity of algae as well as of heterotrophic protists were analyzed over two years in order to assess the effect of environmental parameters on heterotrophic euglenoids. The major diversity of osmotrophs was found in acidic wetlands (i.e., peat bogs), while the majority of phagotrophs were detected in polytrophic sites. This was also illustrated by the correlation of heterotrophic euglenoids with other groups of organisms and other biotic parameters related to the trophic level at the sampling sites. Apparently, habitats with well-developed macrovegetation harboured the highest alpha diversity of heterotrophic euglenoids. Noteworthy, most taxa were found during summer and fall. Additional ecological data on rarely reported taxa observed during this survey (<em>Astasia lagenula</em> var. <em>maxima</em>, <em>Calycimonas quinquecarinata</em>, <em>Euglenopsis vacuolata</em>, <em>Heteronema proteus</em>, <em>Heteronema tremulum</em>, <em>Parmidium circulare</em>) were provided as well.</div></div>","PeriodicalId":12042,"journal":{"name":"European journal of protistology","volume":"99 ","pages":"Article 126149"},"PeriodicalIF":1.9,"publicationDate":"2025-04-11","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"143886504","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":2,"RegionCategory":"生物学","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

引用次数: 0

Testate amoebae are informative bioindicators of critically high ammonia deposition on peatlands 遗存变形虫是泥炭地高氨沉降的重要生物指标

IF 1.9 2区生物学

European journal of protistology Pub Date : 2025-03-29 DOI: 10.1016/j.ejop.2025.126147

Callum R.C. Evans , David A. Hatton , Graeme T. Swindles

{"title":"Testate amoebae are informative bioindicators of critically high ammonia deposition on peatlands","authors":"Callum R.C. Evans , David A. Hatton , Graeme T. Swindles","doi":"10.1016/j.ejop.2025.126147","DOIUrl":"10.1016/j.ejop.2025.126147","url":null,"abstract":"<div><div>The global nitrogen cycle has been majorly disrupted by anthropogenic activity. While nitrogen emissions in the UK and Ireland are declining, ammonia (NH<sub>3</sub>) remains a significant exception. NH<sub>3</sub> emissions are mostly agriculturally sourced and deposited on nearby habitats at high rates in both countries. Peatlands are globally important wetlands that are vulnerable to NH<sub>3</sub> deposition. Essential peatland restoration risks being diminished by excessive NH<sub>3</sub> deposition, leading to the loss of valuable ecosystem services. This study investigates testate amoebae (indicators of contemporary and historic peatland conditions) as bioindicators of seasonal NH<sub>3</sub> deposition on six peatlands across Northern Ireland, UK. <em>Sphagnum</em>, an NH<sub>3</sub>-sensitive bryophyte, was sampled adjacent to NH<sub>3</sub> monitoring sites once per season for a year. When NH<sub>3</sub> deposition was critically high, multivariate analysis demonstrates a link between NH<sub>3</sub> and testate amoebae assemblage change. Similarly, at high NH<sub>3</sub> deposition sites, testate amoebae taxa diversity is observed to be significantly reduced in springtime, when it is expected to be highest. Although, in response to high NH<sub>3</sub> deposition large algivorous taxa do not proliferate as was anticipated, and mixotrophic taxa abundance decreases could not be linked primarily to NH<sub>3</sub>. This research demonstrates the continued potential of testate amoebae as highly informative peatland bioindicators.</div></div>","PeriodicalId":12042,"journal":{"name":"European journal of protistology","volume":"99 ","pages":"Article 126147"},"PeriodicalIF":1.9,"publicationDate":"2025-03-29","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"143830306","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":2,"RegionCategory":"生物学","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

引用次数: 0

A remarkable new monothalamid (Rhizaria, Foraminifera) from the shoreline of Livingston Island, Antarctica 南极洲利文斯顿岛海岸线上发现的一种非凡的新单thalamid （Rhizaria, Foraminifera）

IF 1.9 2区生物学

European journal of protistology Pub Date : 2025-03-29 DOI: 10.1016/j.ejop.2025.126148

Marcel Dominik Solbach , Ferry Siemensma , Maria Holzmann

引用次数: 0

Characterization of the macronuclear and micronuclear pheromone genes of Euplotes raikovi reveals the origin of the mating type genetic diversity 大核和微核信息素基因的分析揭示了交配型遗传多样性的起源

IF 1.9 2区生物学

European journal of protistology Pub Date : 2025-03-22 DOI: 10.1016/j.ejop.2025.126146

Jianjun Huang , Ruitao Gong , Khaled A.S. Al-Rasheid , Feng Gao , Adriana Vallesi , Yaohan Jiang

{"title":"Characterization of the macronuclear and micronuclear pheromone genes of Euplotes raikovi reveals the origin of the mating type genetic diversity","authors":"Jianjun Huang , Ruitao Gong , Khaled A.S. Al-Rasheid , Feng Gao , Adriana Vallesi , Yaohan Jiang","doi":"10.1016/j.ejop.2025.126146","DOIUrl":"10.1016/j.ejop.2025.126146","url":null,"abstract":"<div><div>Ciliates produce diffusible, cell-type-specific pheromones to regulate growth and mating. In <em>Euplotes</em>, these signaling molecules belong to species-specific families of disulfide-rich and structurally homologous proteins. Pheromones are co-dominantly expressed by genes in the somatic macronucleus (MAC), whereas their allelic diversity originates from the <em>mating type locus</em> in the germline micronucleus (MIC). During MAC development in sexual process, the MIC-derived diversity of specific alleles is rearranged via macronucleus-destined sequences (MDSs) assembly. While many MAC pheromones are well characterized, their MIC precursors and rearrangement process remain unknown. Here, we identified two MAC pheromone genes (<em>mac-er-13/14</em>) of <em>E. raikovi</em>, and two MIC regions (19 kb in total) containing 10 MDSs that assemble into <em>mac-er-13</em>. These MDSs are separated by internal eliminated sequences (234–3345 bp). The shortest MDSs (9–36 bp) encode the secreted region of pheromone, while longer MDSs (44–419 bp) encode other regions. Considering that the secreted regions show a higher sequence variation and the shorter MDSs have higher probability of alternative processing or imprecise assembly, we hypothesize that the high sequence variability of the macronuclear pheromone genes, which underlies the large number of mating types in <em>E. raikovi</em>, may result from alternative processing or imprecise assembly of these short MDSs.</div></div>","PeriodicalId":12042,"journal":{"name":"European journal of protistology","volume":"99 ","pages":"Article 126146"},"PeriodicalIF":1.9,"publicationDate":"2025-03-22","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"143747533","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":2,"RegionCategory":"生物学","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

引用次数: 0

Exploring the diversity of Brachonella: Morphological and molecular analysis with the discovery of a new species, Brachonella tenuicauda nov. spec. (Ciliophora, Armophorea, Metopida) 探索 Brachonella 的多样性：通过形态学和分子分析发现新物种 Brachonella tenuicauda nov.(纤毛虫纲，腕足动物，甲壳纲）

IF 1.9 2区生物学

European journal of protistology Pub Date : 2025-03-17 DOI: 10.1016/j.ejop.2025.126142

Nanda Dwi Kristanti, Quoc Dung Nguyen, Mann Kyoon Shin

{"title":"Exploring the diversity of Brachonella: Morphological and molecular analysis with the discovery of a new species, Brachonella tenuicauda nov. spec. (Ciliophora, Armophorea, Metopida)","authors":"Nanda Dwi Kristanti, Quoc Dung Nguyen, Mann Kyoon Shin","doi":"10.1016/j.ejop.2025.126142","DOIUrl":"10.1016/j.ejop.2025.126142","url":null,"abstract":"<div><div>Recently, the interest in studying anaerobic ciliates, particularly armophorean ciliates of the family Metopidae, has increased. The genus <em>Brachonella</em>, a member of this family, currently comprises eight species. However, only four of them have been comprehensively described, with <em>B. contorta</em>, the type species of <em>Brachonella</em>, being the subject of extensive global distribution analyses. This study presents a comprehensive morphological and molecular phylogenetic analysis of <em>B. tenuicauda</em> nov. spec., <em>B. elongata</em>, and <em>B. pulchra. Brachonella tenuicauda</em> is characterized by a tail-like posterior body end and by clusters of two to four dikinetids in the preoral dome kineties. <em>Brachonella elongata</em> is identified by its slender, elongated body without posterior constriction, whereas <em>B. pulchra</em> shows a broadly ellipsoidal to nearly obovoid body. Korean populations of <em>B. pulchra</em> and <em>B. tenuicauda</em> exhibit a diplostichomonad paroral membrane, a feature not previously documented for this genus. Phylogenetic analysis of 18S rDNA sequences indicates non-monophyly of the family Metopidae. Conversely, the genus <em>Brachonella</em> is depicted as monophyletic with full support, confirming its molecular distinctness from other metopid genera.</div></div>","PeriodicalId":12042,"journal":{"name":"European journal of protistology","volume":"99 ","pages":"Article 126142"},"PeriodicalIF":1.9,"publicationDate":"2025-03-17","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"143792080","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":2,"RegionCategory":"生物学","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

引用次数: 0

Phylogeny, morphology, and ultrastructure of sessilid peritrich ciliates in termite guts, Termitophrya africana and Doliophrys denislynni gen. nov., sp. nov. 非洲白蚁和白蚁肠道中无丝纤维纤毛虫的系统发育、形态和超微结构。

IF 1.9 2区生物学

European journal of protistology Pub Date : 2025-03-07 DOI: 10.1016/j.ejop.2025.126140

Renate Radek , Janneke Hassler , Katja Platt , Hisar Ahmad , Thomas Fromm , Michaela Strüder-Kypke , David Sillam-Dussès , Jiří Synek , Jan Šobotník , Vincent Hervé , Andreas Brune

{"title":"Phylogeny, morphology, and ultrastructure of sessilid peritrich ciliates in termite guts, Termitophrya africana and Doliophrys denislynni gen. nov., sp. nov.","authors":"Renate Radek , Janneke Hassler , Katja Platt , Hisar Ahmad , Thomas Fromm , Michaela Strüder-Kypke , David Sillam-Dussès , Jiří Synek , Jan Šobotník , Vincent Hervé , Andreas Brune","doi":"10.1016/j.ejop.2025.126140","DOIUrl":"10.1016/j.ejop.2025.126140","url":null,"abstract":"<div><div>Sessilids (Oligohymenophorea, Peritrichia, Sessilida) reportedly colonize the gut of certain “higher termites” (family Termitidae), but only a single species, <em>Termitophrya africana</em> from <em>Jugositermes tuberculatus</em> (subfamily Apicotermitinae), has been described based on a drawing. Similar ciliates were observed in other Apicotermitinae but remained unspecified<em>.</em> Our SSU rRNA gene-based survey of peritrich ciliates in a broad range of Termitidae recovered distinct phylotypes from several Apicotermitinae (<em>Astalotermes</em>, <em>Jugositermes</em>, and <em>Phoxotermes</em>), albeit only from samples collected in Cameroon and not from all species of these genera. They form a monophyletic group in the family Epistylididae (Sessilida), with <em>Orborhabdostyla bromelicola</em> as the closest relative. Light, scanning, and transmission electron microscopy of the sessilid ciliates in <em>J. tuberculatus</em> revealed two morphotypes, which were assigned to their corresponding phylotypes by sequence analysis of capillary-picked single cells. One morphotype, which is highly contractile and broadens continuously towards the posterior end, matches the description of <em>Termitophrya africana</em>. The cells are attached by a posterior scopula with short cilia and are often covered with rod-shaped ectobionts. The other morphotype has a stockier, barrel-shaped body and a short, clearly demarcated anterior end and is always free of ectobionts. We designate it as <em>Doliophrys denislynni</em> gen. nov., sp. nov.</div></div>","PeriodicalId":12042,"journal":{"name":"European journal of protistology","volume":"99 ","pages":"Article 126140"},"PeriodicalIF":1.9,"publicationDate":"2025-03-07","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"143704986","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":2,"RegionCategory":"生物学","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"OA","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

引用次数: 0

Armaparvus browni sp. nov. (Amoebozoa, Cutosea) isolated from an inland brackish water biotope 棕Armaparvus browni sp. 11 .（变形虫，龟海）从内陆咸淡水生物群落分离

IF 1.9 2区生物学

European journal of protistology Pub Date : 2025-03-04 DOI: 10.1016/j.ejop.2025.126139

Alexander Kudryavtsev , Mikhail Krendelev, Ekaterina Piven, Ekaterina Volkova

{"title":"Armaparvus browni sp. nov. (Amoebozoa, Cutosea) isolated from an inland brackish water biotope","authors":"Alexander Kudryavtsev , Mikhail Krendelev, Ekaterina Piven, Ekaterina Volkova","doi":"10.1016/j.ejop.2025.126139","DOIUrl":"10.1016/j.ejop.2025.126139","url":null,"abstract":"<div><div>A tiny amoebozoan with a locomotive size of about 10 μm was isolated from an inland brackish water biotope in the northwest of Russia. During locomotion, amoebae were flattened, with broad anterior hyaloplasm and short ventral subpseudopodia that appeared like small bumps. Electron microscopy shows that amoebae are enclosed in a flexible layer of flat oval scales embedded in a matrix and separated from the plasma membrane surface. These characters are in accordance with the phylogenetic placement of this strain, as reconstructed using the nuclear SSU rRNA, actin, and mitochondrial cytochrome <em>c</em> oxidase subunit 1 (Cox1) gene sequences. Morphology and molecular phylogenies warrant the description of the studied strain as a new species, <em>Armaparvus browni</em> sp. nov. This species shows a broad range of salinity tolerance, being able to reproduce in culture under salinity of 2.5 ‰, but not in 0.3 ‰ or artificial freshwater medium. This may be due to an adaptation to brackish water with oscillating salinity and hence <em>A. browni</em> probably cannot expand into truly freshwater habitats.</div></div>","PeriodicalId":12042,"journal":{"name":"European journal of protistology","volume":"98 ","pages":"Article 126139"},"PeriodicalIF":1.9,"publicationDate":"2025-03-04","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"143637773","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":2,"RegionCategory":"生物学","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

引用次数: 0

Morphology and molecular phylogeny of a new hypotrichous ciliate, Sterkiella zhangi n. sp. (Ciliophora, Oxytrichidae) 一种新的次毛纤毛虫，Sterkiella zhangi n. sp.（纤毛虫目，毛虱科）的形态和分子系统发育

IF 1.9 2区生物学

European journal of protistology Pub Date : 2025-03-02 DOI: 10.1016/j.ejop.2025.126141

Miaomiao Wang, Tao Hu, Shanshan Wang, Zhangwen Tong, Qianqian Wei, Xinpeng Fan

{"title":"Morphology and molecular phylogeny of a new hypotrichous ciliate, Sterkiella zhangi n. sp. (Ciliophora, Oxytrichidae)","authors":"Miaomiao Wang, Tao Hu, Shanshan Wang, Zhangwen Tong, Qianqian Wei, Xinpeng Fan","doi":"10.1016/j.ejop.2025.126141","DOIUrl":"10.1016/j.ejop.2025.126141","url":null,"abstract":"<div><div>The morphology, morphogenesis, and molecular phylogeny of a new hypotrichous ciliate, <em>Sterkiella zhangi</em> n. sp., which originated from terrestrial moss collected in east China, were studied using live observation, protargol staining, and the macronuclear SSU rRNA and mitochondrial cytochrome <em>c</em> oxidase subunit 1 gene sequences. The new species can be distinguished from its congeners by the following characteristics: three ordinary frontal cirri (an extra small frontal cirrus present in half of the individuals examined), an average of 15 left and 16 right marginal cirri, five transverse cirri, two macronuclear nodules, and cyst surface with irregular wrinkles but without spines. The 1:3:3:3:4:4 frontal-ventral-transverse anlagen fragmentation pattern of <em>S. zhangi</em> n. sp. indicates that the extra frontal cirrus is very likely a retained parental structure. Phylogenetic analyses revealed that the new species branches early in the subfamily Stylonychinae. The comparison of mitochondrial cytochrome <em>c</em> oxidase subunit 1 gene sequences of <em>Sterkiella</em> species shows that the intra-specific variation is much smaller than the inter-specific divergence. The well-known model organism <em>Oxytricha trifallax</em> has accumulated significant evolutionary differences and should be treated as a distinct species rather than a synonym of <em>S. histriomuscorum</em>.</div></div>","PeriodicalId":12042,"journal":{"name":"European journal of protistology","volume":"98 ","pages":"Article 126141"},"PeriodicalIF":1.9,"publicationDate":"2025-03-02","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"143593316","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":2,"RegionCategory":"生物学","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

引用次数: 0