Protist最新文献_第3页

Soil ciliates' response to glyphosate exposure: A microcosm experiment 土壤纤毛虫对草甘膦暴露的反应：一个微观实验

IF 1.9 3区生物学 Q4 MICROBIOLOGY

Protist

Pub Date : 2025-09-01 Epub Date: 2025-07-02 DOI: 10.1016/j.protis.2025.126112

Hai T.T. Luu , Genoveva F. Esteban , Iain D. Green

The widespread use of glyphosate, a broad-spectrum herbicide, in agriculture raises concerns about its impact on non-target organisms and ecosystem functions. Research on glyphosate's effect on soil microorganisms has been inconsistent due to varying methodologies and focuses. To address this, a controlled microcosm study was conducted to investigate glyphosate's impact on soil ciliates, an essential component of soil microbial communities. This study is among the first to examine glyphosate impact on ciliates. The experiment used agricultural soil with glyphosate applied at standard and elevated rates. Ciliate abundance and species richness were monitored in the microcosms at 1-, 7-, and 15-days post-application. Soil ciliates showed remarkable tolerance to glyphosate at standard application rates, with a notable increase in abundance after 15 days, primarily driven by one species' proliferation. This study demonstrates the resilience of ciliate communities to standard glyphosate rates, suggesting their crucial role in maintaining soil functionality in the presence of the herbicide. However, it also highlights potential ecological risks at higher glyphosate concentrations, as evidenced by the loss of ciliate species at the highest rates tested. These findings contribute to our understanding of glyphosate's impact on soil ecosystems and highlights the importance of further research in this area.

草甘膦是一种广谱除草剂，在农业中的广泛使用引起了人们对其对非目标生物和生态系统功能的影响的担忧。关于草甘膦对土壤微生物影响的研究，由于方法和重点的不同，一直不一致。为了解决这个问题，进行了一项对照微观研究，以研究草甘膦对土壤纤毛虫的影响，纤毛虫是土壤微生物群落的重要组成部分。这项研究是首批研究草甘膦对纤毛虫影响的研究之一。试验使用农用土壤，草甘膦按标准和高施用量施用。在施用后1、7和15 d监测微环境中纤毛虫的丰度和物种丰富度。在标准施用量下，土壤纤毛虫对草甘膦表现出显著的耐受性，15 d后丰度显著增加，主要是由一个物种的增殖驱动。这项研究证明了纤毛虫群落对标准草甘膦浓度的恢复能力，表明它们在除草剂存在下维持土壤功能的关键作用。然而，它也强调了草甘膦浓度较高时的潜在生态风险，所测试的最高比率的纤毛虫物种损失证明了这一点。这些发现有助于我们了解草甘膦对土壤生态系统的影响，并强调了在这一领域进一步研究的重要性。

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引用次数: 0

Characterizing lineage-specific genes in testate lobose amoebae (Arcellinida) 雄性叶状变形虫（Arcellinida）谱系特异性基因的研究

IF 2.1 3区生物学 Q4 MICROBIOLOGY

Protist

Pub Date : 2025-09-01 Epub Date: 2025-08-05 DOI: 10.1016/j.protis.2025.126115

Angela K. Jiang , Taylor R. Sehein , Rebecca Gawron , Laura A. Katz , Xyrus X. Maurer-Alcalá

Arcellinida are an abundant and diverse order of testate (shelled) amoebae that are important bioindicators of changing climates. Despite their ecological importance, the molecular mechanisms that underlie their adaptations, including those involving lineage-specific genes, remain largely unknown. Lineage-specific gene families (LSGFs) are linked to evolutionary innovations, yet the evolution of LSGFs remains underexplored across the tree of life, with most research restricted to model eukaryotes. Here, we assess the evolution of Arcellinida-specific gene families using a set of 197 Arcellinida transcriptomes representing 12 Arcellinida genera. We employ a conservative filtering approach to identify 3424 Arcellinda-specific gene families. Our analyses show that these lineage-specific gene families are shorter and exhibit lower expression compared to more conserved genes, congruent with trends observed in other eukaryotic lineages. Although there are inherent limitations regarding missing data with transcriptomics, we recover substantially more lineage-specific gene family births in the symbiont-bearing species Hyalosphenia papilio compared to Hyalosphenia elegans. Our results demonstrate a method to identify lineage-specific genes in non-model organisms where no reference genome are available, and expand our understanding of the evolution of lineage-specific genes in eukaryotes.

Arcellinida是一种数量丰富、种类多样的有壳变形虫目，是气候变化的重要生物指示物。尽管它们具有重要的生态意义，但它们适应的分子机制，包括那些涉及谱系特异性基因的分子机制，在很大程度上仍然未知。谱系特异性基因家族（LSGFs）与进化创新有关，但LSGFs的进化在整个生命树中仍未得到充分探索，大多数研究仅限于模型真核生物。在这里，我们使用代表12个Arcellinida属的197个Arcellinida转录组来评估Arcellinida特异性基因家族的进化。我们采用保守过滤方法鉴定了3424个arcellinda特异性基因家族。我们的分析表明，与更保守的基因相比，这些谱系特异性基因家族更短，表达量更低，这与在其他真核生物谱系中观察到的趋势一致。尽管转录组学数据缺失存在固有的局限性，但与秀丽透明蝶相比，我们在共生物种中恢复了更多的谱系特异性基因家族出生。我们的研究结果展示了一种在没有参考基因组的非模式生物中鉴定谱系特异性基因的方法，并扩大了我们对真核生物谱系特异性基因进化的理解。

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引用次数: 0

The first record of a gregarine from the family Urosporidae (Apicomplexa: Lecudinoidea) in a bivalve mollusc, Axinopsida orbiculata 文章标题双壳软体动物尾孢子虫科（顶复合体：尾孢子虫总科）中尾孢子虫的首次记录

IF 2.1 3区生物学 Q4 MICROBIOLOGY

Protist

Pub Date : 2025-09-01 Epub Date: 2025-08-06 DOI: 10.1016/j.protis.2025.126116

Valentin Kokarev, Suzanne C. Dufour

Urosporid gregarines are an understudied group of coelomic and intestinal extracellular parasites of marine invertebrates. To date, they have been recorded in various hosts, including annelids, nemerteans, echinoderms and gastropods. In the present paper, we describe a new urosporid gregarine, Gonospora axinopsidae sp. nov., the first in this family known to infect a bivalve mollusc, Axinopsida orbiculata. Trophozoites and oocysts within gametocysts were observed within the bivalve's mantle cavity and hemocoel. The morphology and ultrastructure of these life stages are described using scanning and transmission electron microscopy. The 18S rRNA sequence of Gonospora axinopsidae sp. nov. suggests strong phylogenetic affinity with the genus Difficilina, which infects the intestine of nemerteans. This report increases the known host range of urosporid gregarines. The described morphological and genetic characteristics of Gonospora axinopsidae sp. nov. can support further studies aiming to elucidate phylogenetic relationships within marine gregarines.

尾孢虫是一种海洋无脊椎动物体腔和肠道细胞外寄生虫。到目前为止，它们已经在各种各样的宿主中被记录下来，包括环节动物、水母、棘皮动物和腹足动物。在本文中，我们描述了一种新的泌尿孢子虫，axinopsidae sp. nov.，这是该家族中已知的第一个感染双壳类软体动物Axinopsida orbiculata的。在双壳类动物的套腔和血腔内观察到滋养体和配子体中的卵囊。用扫描电镜和透射电镜描述了这些生命阶段的形态和超微结构。axinopsidae sp.十一月Gonospora axinopsidae sp. 11 .的18S rRNA序列表明与感染nemerteans肠道的艰难梭菌属有很强的系统亲缘关系。该报告增加了已知的尿孢子虫的宿主范围。所描述的雨淋孢子虫的形态和遗传特征可以为进一步阐明海洋格林虫的系统发育关系提供支持。

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引用次数: 0

Morphology and ultrastructure of marine bacterivorous bicosoecid Hirugamonas aperieos gen. et sp. nov. 海洋嗜菌生物鱿鱼的形态和超微结构。

IF 1.9 3区生物学 Q4 MICROBIOLOGY

Protist

Pub Date : 2025-09-01 Epub Date: 2025-06-02 DOI: 10.1016/j.protis.2025.126104

Tatsuya Kishikami, Marina Ota, Kasumi Ishida, Kazumasa Yamada, Takafumi Kataoka

Heterotrophic nanoflagellates (HNF) are recognized as active bacterivores in marine environments. We report the isolation and culture of a strain of HNF obtained from the seawater of Lake Hiruga. The organism has two flagella of different length, a long anterior flagellum with tripartite mastigonemes and a short smooth posterior flagellum; a spiral fiber was observed in the transition zone of the flagella. The spherical or D-shaped cell has a groove with one stretchable edge and is supported by 6–8 microtubule bundle that extends from the basal bodies and forms a cytostome. Additionally, the isolate lacked lorica, body scales, cytopharynx, or acronematic structure of flagella, and thus it could not be assigned to any known genera in the order Bicosoecida. Phylogenetic analysis of 18S rRNA gene sequences from Bicosoecida confirmed an independent clade at the genus level with the closest relative genus being Bicosoeca. The optimal salinity and temperature ranges for growth was 21 %–30 % and 25–31 °C, respectively, indicating a marine mesophilic HNF. Thus, based on the morphological features and phylogenetic analysis of 18S rRNA gene sequences, we propose a novel genus for the isolate: Hirugamonas, n. gen. The species name Hirugamonas aperieos sp. nov. is proposed.

异养纳米鞭毛虫（HNF）被认为是海洋环境中活跃的细菌捕食者。我们报道了从平贺湖海水中分离和培养的一株HNF。该生物有两个不同长度的鞭毛，前鞭毛长且有三节鞭毛，后鞭毛短而光滑；鞭毛过渡区有螺旋状纤维。球形或d形细胞具有具有一个可拉伸边缘的凹槽，并由6-8微管束支撑，该微管束从基底延伸并形成细胞壁。此外，该分离物缺乏鞭毛、体鳞、细胞咽或鞭毛的首字母缩略结构，因此它不能被分配到任何已知的生物虫目属。对其18S rRNA基因序列进行系统发育分析，证实其属水平上为独立支系，最近的亲缘属为Bicosoeca。生长的最佳盐度和温度范围分别为21% ~ 30%和25 ~ 31℃，为海洋中温型HNF。因此，基于18S rRNA基因序列的形态特征和系统发育分析，我们提出了该分离物的新属：Hirugamonas， n. gen.，种名为Hirugamonas aperieos sp. nov。

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引用次数: 0

NGS-based detection and differentiation of Entamoeba in Algerian wildlife and domestic animals 阿尔及利亚野生动物和家畜内阿米巴原虫的ngs检测与分化

IF 2.1 3区生物学 Q4 MICROBIOLOGY

Protist

Pub Date : 2025-09-01 Epub Date: 2025-08-13 DOI: 10.1016/j.protis.2025.126118

Meriem Ali Zouaoui , Asma Guilane , Lee O'Brien Andersen , Fadila Tazerouti , Amina Boutellis , Christen Rune Stensvold

This study investigated the distribution and genetic diversity of Entamoeba in 217 faecal samples from mammals, birds, rodents, reptiles, amphibians, fish, and invertebrates sampled across Algeria. By next-generation sequencing (NGS)-based metabarcoding of SSU rDNA, an overall positivity rate of 13 % (n = 29/217) was observed, with positive cases limited to five host families: Bovidae, Camelidae, Equidae, Cervidae, and Caviidae, all of which are herbivores. From the 34 established cluster consensus sequences, we identified one species: Entamoeba bovis, two ribosomal lineages (RL1 and RL8), three conditional lineages (CL3, CL4, and CL10), and one already described sequence type, SQT-A, expanding on the known host range of previously identified Entamoeba. Also, nine novel sequences types (SQT-K to SQT-S) were proposed. Massive genetic diversity was observed, with mixed infections detected in all positive samples. Phylogenetic analyses revealed both generalist and host-specific clusters. Significant genetic similarities between the taxa identified in this study and those previously documented in hosts from Greenland were documented. We observed that herbivores are infected by multiple Entamoeba taxa, a pattern also reported in previous studies. This study highlights the power of molecular tools such as NGS and metabarcoding in deciphering complex Entamoeba co-infections, providing valuable insights into host-parasite interactions.

本研究调查了阿尔及利亚全国哺乳动物、鸟类、啮齿动物、爬行动物、两栖动物、鱼类和无脊椎动物的217份粪便样本中内阿米巴原虫的分布和遗传多样性。基于下一代测序（NGS）的SSU rDNA元编码结果显示，总阳性率为13% (n = 29/217)，阳性病例局限于5个寄主科：牛科、驼科、马科、鹿科和穴居动物，均为食草动物。从34个已建立的聚类一致序列中，我们确定了一个物种：牛内阿米巴，两个核糖体谱系（RL1和RL8），三个条件谱系（CL3， CL4和CL10），以及一个已经描述的序列类型SQT-A，扩展了先前鉴定的内阿米巴已知宿主范围。此外，还提出了9种新的序列类型（SQT-K ~ SQT-S）。观察到大量的遗传多样性，在所有阳性样本中检测到混合感染。系统发育分析显示了通用性和宿主特异性群集。本研究中鉴定的分类群与以前在格陵兰岛宿主中记录的分类群之间存在显著的遗传相似性。我们观察到食草动物被多个内阿米巴类群感染，这种模式在以前的研究中也有报道。这项研究强调了分子工具（如NGS和元条形码）在破译复杂的内阿米巴合并感染方面的力量，为宿主-寄生虫相互作用提供了有价值的见解。

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引用次数: 0

Morphology and taxonomy of a new species of a rare genus Paracolpidium (Ciliophora, Oligohymenophorea), P. harbinense sp. nov. from Northeast China 东北疏膜蜂属一新种的形态与分类

IF 1.9 3区生物学 Q4 MICROBIOLOGY

Protist

Pub Date : 2025-06-01 Epub Date: 2025-03-25 DOI: 10.1016/j.protis.2025.126097

Xiang Wang , Bailin Li , Jiarui Wang, Xiaosong Wang, Jialu Wang, Xuming Pan

The morphology and ciliary pattern of a new hymenostomatid ciliate, Paracolpidium harbinense sp. nov., collected from the Songhua River, northeast China, was investigated based on living observation and silver staining. Paracolpidium harbinense sp. nov. is characterized by the following features: body size in vivo about 47–56 μm × 17–26 μm in vivo; cell shape ovate with silghtly curved anterior body end; buccal field about 17 % of body length; 18–20 somatic kineties; oral ciliature consisting of a single paroral membrane and three adoral membranelles; macronucleus globular and accompanied by a single micronucleus; silverline system composed of primary meridians. Phylogenetic analyses based on small subunit ribosomal RNA (SSU rRNA) gene sequences suggest the genus Paracolpidium is closely related to Dexiostoma.

采用活体观察和银染色法对松花江中一种新膜口虫（Paracolpidium harbinense sp. nov.）的形态和纤毛形态进行了研究。哈尔宾副栉水母具有以下特征：体内体型约为47 ~ 56 μm × 17 ~ 26 μm；细胞形状卵形具稍弯曲的前体端；颊部约占体长的17%；18-20体动力学；由一个口外膜和三个口外膜组成的口腔纤毛；大核呈球状，并伴有单个微核；由主经络组成的银线系统。基于小亚单位核糖体RNA （SSU rRNA）基因序列的系统发育分析表明，Paracolpidium属与Dexiostoma密切相关。

引用次数: 0

Transcriptomic analyses reveal sexual cues in reproductive life stages of uncultivated Acantharia (Radiolaria) 转录组学分析揭示了未栽培棘虫（Radiolaria）生殖阶段的性暗示

IF 1.9 3区生物学 Q4 MICROBIOLOGY

Protist

Pub Date : 2025-06-01 Epub Date: 2025-04-28 DOI: 10.1016/j.protis.2025.126102

Iris Rizos , Sarah Romac , Caroline Juery , Charlotte Berthelier , Johan Decelle , Juliana Bernardes , Erwan Corre , Lucie Bittner , Fabrice Not

The ability to reproduce is a key process for the perpetuation of organisms. Along the evolution of protist reproductive strategies, the molecular machinery of sexual recombination is estimated to have been inherited from the last eukaryotic common ancestor (LECA). Unraveling the sexual cycles of free-living protists remains challenging, given the enigmatic roles of many uncultivated life stages. For the planktonic group of Acantharia (Radiolaria), a hypothetical sexual cycle has been proposed since the late 19th century, including a gamete-like stage, referred to as swarmers. In order to investigate the sexual nature of acantharian reproductive stages, we compared transcriptomes of various acantharian life stages. Our results show distinct functional profiles for reproductive and vegetative stages, while revealing the expression of the gamete fusion genes, HAP2/GCS1 and KAR5-GEX1-BMB in swarmers. Annotation of differentially expressed life stage-specific genes, also highlighted putative meiosis-related functions among pre-swarmer and swarmer stages, while suggesting the existence of a putative zygotic stage. This original life stage-specific genetic data is coherent with morphological evidence supporting the acantharian sexual cycle, with swarmers acting as gametes. Moreover, it paves the way for a deeper understanding of radiolarian cell biology and ecology at a single-cell scale.

繁殖能力是生物体永续的关键过程。在原生生物生殖策略的进化过程中，性重组的分子机制估计是从最后的真核生物共同祖先（LECA）那里遗传下来的。考虑到许多未开垦的生命阶段的神秘角色，解开自由生活的原生生物的性周期仍然具有挑战性。对于浮游生物群棘虫（放射虫），一种假设的性循环自19世纪晚期就被提出，包括一个类似配子的阶段，被称为群集。为了研究棘虫生殖阶段的性别性质，我们比较了棘虫不同生命阶段的转录组。我们的研究结果显示了不同的生殖和营养阶段的功能谱，同时揭示了配子融合基因HAP2/GCS1和KAR5-GEX1-BMB在蜂群中的表达。不同表达的生命阶段特异性基因的注释也强调了在蜂群前和蜂群期之间可能存在的减数分裂相关功能，同时表明可能存在合子期。这种原始的生命阶段特异性遗传数据与支持棘虫性循环的形态学证据是一致的，蜂群充当配子。此外，它为在单细胞尺度上更深入地了解放射虫细胞生物学和生态学铺平了道路。

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引用次数: 0

Morphology and phylogeny of Prorocentrum venetum Tolomio & Cavolo (Dinophyceae) 龙足科原中央兽类的形态与系统发育

IF 1.9 3区生物学 Q4 MICROBIOLOGY

Protist

Pub Date : 2025-06-01 Epub Date: 2025-04-03 DOI: 10.1016/j.protis.2025.126099

Daniel Grzebyk , Mona Hoppenrath , Urban Tillmann

Prorocentrum venetum was one of the first species of the genus Prorocentrum described by scanning electron microscopy by Tolomio and Cavolo in 1985. Since the first observation of the species in the Venice Lagoon (Italy) in summer 1981, it has not been reported again in published phytoplankton records of Mediterranean waters or elsewhere. Two strains were isolated from a French Mediterranean lagoon, which were morphologically identified as P. venetum by microscopy. Based on rDNA sequences (spanning the 18S to the D3 region of 28S rDNA), the phylogenetic analysis demonstrated that P. venetum belongs to the same clade as Prorocentrum triestinum and Prorocentrum redfieldii. The analysis of scanning electron micrographs provided an in-depth morphological description of the theca, particularly on the pore pattern of thecal plates and new structural details of the platelets in the periflagellar area. These morphological characteristics were compared with the closely related species within the P. triestinum clade, which showed synapomorphic characters in the periflagellar area (small accessory pore, platelet pattern, shape of the apical wing). Further comparison of characteristics varying between species in this clade and in the sister clade encompassing species related to Prorocentrum micans suggests some features of morphological evolution within this part of the genus.

proorocentrum venetum是Tolomio和Cavolo于1985年通过扫描电子显微镜发现的proorocentrum属植物之一。自1981年夏天在威尼斯泻湖（意大利）首次观察到该物种以来，在地中海水域或其他地方发表的浮游植物记录中没有再报道过。从法国地中海泻湖分离出两株，镜检形态鉴定为威尼斯假单胞菌。基于rDNA序列（从18S到28S rDNA的D3区），系统发育分析表明，P. venetum与proorocentrum triestinum和proorocentrum redfieldii属于同一支系。扫描电镜分析提供了对鞘膜的深入形态学描述，特别是鞘板的孔隙模式和鞭毛周围区域血小板的新结构细节。这些形态特征与近缘种在鞭毛周围区（小副孔、血小板图案、顶翅形状）表现出突触性特征进行了比较。进一步比较这一分支中不同物种之间的特征差异和包含micans原中心心相关物种的姊妹分支表明，这部分属的一些形态进化特征。

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引用次数: 0

Unveiling the remarkable diversity of the genus Hypotrichomonas (Parabasalia: Hypotrichomonadidae) in cockroaches (Blattodea, excluding Isoptera) 揭示蟑螂（小蠊总目，不包括等翅目）中滴虫属（副滴虫目：滴虫科）的显著多样性

IF 1.9 3区生物学 Q4 MICROBIOLOGY

Protist

Pub Date : 2025-06-01 Epub Date: 2025-04-15 DOI: 10.1016/j.protis.2025.126100

Michael Kotyk , Zuzana Kotyková Varadínová , Pavla Hrubá , Ivan Čepička

Parabasalid hindgut symbionts of the xylophagous Isoptera/Cryptocercus lineage (Blattodea: Blattoidea) have been attracting the interest of biologists for decades. However, the parabasalids from other cockroaches (Blattodea excluding Isoptera) remain largely unstudied. The genus Hypotrichomonas, along with genus Trichomitus, belongs to the small parabasalid order Hypotrichomonadida. So far, ten valid Hypotrichomonas species have been described from animals, both vertebrates and invertebrates. Here we have uncovered an extensive diversity of this genus in cockroaches. We have obtained 72 isolates from 41 cockroach species and one from a water-filled tree hole. Using a combination of light-microscopic morphology of protargol-stained cells, scanning electron microscopy, and a phylogenetic analysis of SSU rRNA gene, we show that our strains represent multiple novel Hypotrichomonas species, and we formally describe seven of them. Our data show that the evolutionary center of the genus likely lies in cockroaches. Moreover, the new evolutionary lineages of Hypotrichomonas from cockroaches show a high degree of host specificity.

几十年来，食木等翅目/隐尾蚴系的副拟虫性后肠共生体一直吸引着生物学家的兴趣。然而，其他蟑螂（不包括等翅目）的拟蠓类仍未被研究。毛滴虫属与毛滴虫属同属副滴虫目。到目前为止，已经从脊椎动物和无脊椎动物中描述了十种有效的下滴虫。在这里，我们发现了蟑螂属的广泛多样性。从41种蟑螂中分离得到72株分离株，其中1株来自一个充满水的树洞。利用原targols染色细胞的光镜形态，扫描电镜和SSU rRNA基因的系统发育分析相结合，我们发现我们的菌株代表了多个新的下滴虫物种，我们正式描述了其中的七个。我们的数据显示，该属的进化中心可能在蟑螂身上。此外，蟑螂下滴虫的新进化谱系显示出高度的宿主特异性。

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引用次数: 0

Description of new diplonemids (Diplonemea, Euglenozoa) and their endosymbionts: Charting the morphological diversity of these poorly known heterotrophic flagellates 新双鞭毛纲（双鞭毛纲，真鞭毛纲）及其内共生生物的描述：绘制这些鲜为人知的异养鞭毛纲的形态多样性

IF 1.9 3区生物学 Q4 MICROBIOLOGY

Protist

Pub Date : 2025-06-01 Epub Date: 2025-02-20 DOI: 10.1016/j.protis.2025.126090

Daria Tashyreva , Jan Votýpka , Akinori Yabuki , Aleš Horák , Julius Lukeš

Diplonemids are a hyperdiverse group of flagellated protists, but with less than two dozen formally described representatives. Here, we describe four new species of cultured diplonemids, identified on the basis of their 18S rRNA sequences, light-, fluorescence-, scanning- and transmission electron microscopy. Three new species belong to the genus Rhynchopus (R. asiaticus sp.n., R. granulatus sp.n., and R. valaseki sp.n.), while the fourth species is an unusual representative of the genus Lacrimia (L. aflagellata sp.n.). The latter organism is the first diplonemid outside the genus Rhynchopus (as defined previously) to show a gliding trophic stage with flagellar stubs concealed inside the flagellar pocket and a highly motile dispersive swimming stage. Since this character is thus no longer a genus-specific apomorphy, we provide a taxonomic revision of the genus Rhynchopus with separation of the new genus Natarhynchopus gen. n. We also identify bacterial endosymbionts of L. aflagellata and R. asiaticus as Ca. Syngnamydia medusae (Chlamydiales, Simkaniaceae) and Ca. Cytomitobacter rhynchopi sp. n. (Alphaproteobacteria, Holosporaceae), respectively, and discuss their potential functions. This is the first report of a chlamydial symbiont within a diplonemid host. We also propose that diplonemids may serve as vectors for chlamydial pathogens of marine fish.

双尾虫是一个高度多样化的鞭毛原生生物群体，但只有不到24个正式描述的代表。在这里，我们描述了四种新的培养双花属植物，根据它们的18S rRNA序列，光，荧光，扫描和透射电子显微镜鉴定。文章属三新种（R. asiaticus sp.n.）。；；；；第4种为泪虫属（L. aflagellata sp.n.）的罕见代表种。后一种生物是除Rhynchopus属（如前所述）外第一个显示出滑翔营养阶段（鞭毛残根隐藏在鞭毛袋内）和高度运动性分散游泳阶段的双翅虫。由于这一特征不再是属特异性的无形态，我们对Rhynchopus属进行了分类修订，分离出了新属Natarhynchopus gen. n。我们还鉴定了L. aflagellata和R. asiaticus的细菌内共生体分别为Ca. Syngnamydia medusae （Chlamydiales, Simkaniaceae）和Ca. Cytomitobacter rhynchopi sp. n. (Alphaproteobacteria, Holosporaceae)，并讨论了它们的潜在功能。这是首次在双孔虫寄主体内发现衣原体共生体。我们还提出双孔虫可能是海鱼衣原体病原体的载体。

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引用次数: 0