Abstract：
:We observed reproductive swarmer cells of the nassellarian and spumellarian polycystine radiolarians Didymocyrtis ceratospyris, Pterocanium praetextum, Tetrapyle sp., and Triastrum aurivillii using light, scanning and transmission electron microscopy. The swarmer cells had subspherical to ovoid or spindle shapes with two unequal flagella tapered to whip-like ends. The cell size was approximately 2.5-5.5μm long and 1.6-2.2μm wide, which is significantly smaller than that of the collodarian (colonial or naked) polycystine radiolarians. Transmission electron microscopy revealed that the swarmer cells possessed a nucleus, mitochondria with tubular cristae, Golgi body, and small lipid droplets in the cytoplasm; they also had a large vacuole in which a single crystalline inclusion (approx. 1.0-1.5μm) that was probably celestite (SrSO4) was enclosed. The swarmer cells were released directly from the parent cells. At that time, morphological change such as encystment was not observed in the parent cells, and the axopodia remained extended in a period of swarmer reproduction for floating existence. This may have prevented the polycystine swarmers from rapidly sinking down to great depths. Thus, we concluded that the polycystine radiolarians release the swarmer cells into the photic layer in the same way as the symbiotic acantharians.
journal_name
Eur J Protistoljournal_title
European journal of protistologyauthors
Yuasa T,Takahashi Odoi
10.1016/j.ejop.2016.02.007subject
Has Abstractpub_date
2016-06-01 00:00:00pages
19-32eissn
0932-4739issn
1618-0429pii
S0932-4739(16)30007-4journal_volume
54pub_type
杂志文章abstract：:A new species of unicellular opisthokont protist, Nuclearia thermophila sp. nov., was isolated from the warm spring water of Yunoko Lake, Japan, and has been described using light and electron microscopy. It exists as a spherical floating form and a flattened amoeboid form showing various shapes. The cells occasionall...
journal_title：European journal of protistology
pub_type： 杂志文章
doi：10.1016/j.ejop.2008.09.004
更新日期：2009-05-01 00:00:00
abstract：:Microbial eukaryotes living in low oxygen environments often have novel physiological and morphological features that facilitate symbiotic relationships with bacteria and other means for acquiring nutrients. Comparative studies of these features provide evidence for phylogenetic relationships and evolutionary history....
journal_title：European journal of protistology
pub_type： 杂志文章
doi：10.1016/j.ejop.2012.07.001
更新日期：2013-01-01 00:00:00
abstract：:I discuss how different feeding modes and related cellular structures map onto the eukaryote evolutionary tree. Centrally important for understanding eukaryotic cell diversity are Loukozoa: ancestrally biciliate phagotrophic protozoa possessing a posterior cilium and ventral feeding groove into which ciliary currents ...
journal_title：European journal of protistology
pub_type： 杂志文章,评审
doi：10.1016/j.ejop.2012.06.001
更新日期：2013-05-01 00:00:00
abstract：:Prorodon spirogyrophagus nov. spec. is described by observations on living and silver-stained specimens. Important morphometric data are presented and the feeding habits are described. The new species is characterized by a body size of about 450 × 200 μm, numerous independently functioning contractile vacuoles each wi...
journal_title：European journal of protistology
pub_type： 杂志文章
doi：10.1016/S0932-4739(89)80009-4
更新日期：1989-07-07 00:00:00
abstract：:Dileptid and tracheliid ciliates have been traditionally classified within the subclass Haptoria of the class Litostomatea. However, their phylogenetic position among haptorians has been controversial and indicated that they may play a key role in understanding litostomatean evolution. In order to reconstruct the evol...
journal_title：European journal of protistology
pub_type： 杂志文章
doi：10.1016/j.ejop.2011.04.006
更新日期：2011-11-01 00:00:00
abstract：:The species Leptomyxa flabellata was described by Goodey in 1915 and re-isolated by Pussard and Pons in 1976. It seems that it was never seen (or never recognized) again since that time. The strain designated as "Leptomyxa flabellata CCAP 1546/2" was studied by Cann in 1984, however the quality of the electron microsc...
journal_title：European journal of protistology
pub_type： 杂志文章
doi：10.1016/j.ejop.2017.12.001
更新日期：2018-02-01 00:00:00
abstract：:The morphology, ontogenesis, conjugation, and phylogenetic position of Metopus boletus nov. spec. were studied using live observation, various silver impregnation methods, scanning electron microscopy, morphometry, and the 18S rRNA gene sequence. The new species is outstanding in having a mushroom-like appearance; a g...
journal_title：European journal of protistology
pub_type： 杂志文章
doi：10.1016/j.ejop.2019.04.002
更新日期：2019-06-01 00:00:00
abstract：:The living morphology, infraciliature and morphogenesis of a new ciliate, Urosomoida paragiliformis n. sp., collected from saline soil in Weinan, China, were studied in vivo and after protargol staining. Urosomoida paragiliformis n. sp. is characterized as follows: body elongate-elliptical with no tail, flexible and s...
journal_title：European journal of protistology
pub_type： 杂志文章,评审
doi：10.1016/j.ejop.2016.07.005
更新日期：2016-10-01 00:00:00
abstract：:The morphology and the infraciliature of Pseudokeronopsis rubra [7, 10, 11], P. carnea [8] nov. comb, and P. flava [8] nov. comb, are redescribed using protargol silver staining, biometry, and chromatography. These species differ in the colour and composition of the pigment granules, the length of the midventral rows,...
journal_title：European journal of protistology
pub_type： 杂志文章
doi：10.1016/S0932-4739(87)80010-X
更新日期：1987-11-01 00:00:00
abstract：:Five scuticociliates, collected from China, were morphologically studied using standard methods One represents a new member of the genus Falcicyclidium, F. citriforme nov. spec., which can be recognised mainly by a combination of the following characters: usually two macronuclear nodules, buccal field about half of bo...
journal_title：European journal of protistology
pub_type： 杂志文章
doi：10.1016/j.ejop.2017.03.003
更新日期：2017-06-01 00:00:00
abstract：:The ultrastructural cytology and reproduction of the hyperparasitic microsporidium Amphiamblys capitellides (Caullery and Mesnil, 1897) is described. Merogonial reproduction was not observed. The sporogony comprises two sequences: a sac-bound sporogony in close contact with the cytoplasm of the host and a free sporogo...
journal_title：European journal of protistology
pub_type： 杂志文章
doi：10.1016/j.ejop.2006.07.001
更新日期：2006-11-01 00:00:00
abstract：:Acanthamoebae feed on bacteria but are also frequent hosts of bacterial symbionts. Here, we describe the stable co-occurrence of two symbionts, one affiliated to the genus Parachlamydia and the other to the candidate genus Paracaedibacter (Alphaproteobacteria), within a clinical isolate of Acanthamoeba hatchetti genot...
journal_title：European journal of protistology
pub_type： 杂志文章
doi：10.1016/j.ejop.2016.04.002
更新日期：2016-10-01 00:00:00
abstract：:Vertical variations in trophic-functional patterns of biofilm-dwelling ciliates were studied in coastal waters of the Yellow Sea, northern China. A total of 50 species were identified and assigned to four trophic-functional groups (TFgrs): algivores (A), bacterivorous (B), non-selective (N) and raptors (R). The trophi...
journal_title：European journal of protistology
pub_type： 杂志文章
doi：10.1016/j.ejop.2018.01.003
更新日期：2018-04-01 00:00:00
abstract：:More than 1000 secretory organelles (trichocysts) are docked at the plasma membrane of Paramecium cells. After stimulation, the trichocyst contents are expelled as needle-like structures in an exocytotic response. Neither the function nor the natural stimulus of trichocyst exocytosis are known in this well established...
journal_title：European journal of protistology
pub_type： 杂志文章
doi：10.1016/S0932-4739(11)80256-7
更新日期：1991-11-29 00:00:00
abstract：:Toxoplasma gondii is a zoonotic parasite with a world-wide distribution. House mice (Mus musculus) play an important role as a reservoir host in the parasite life cycle. However, their detection in mouse brain is limited because the host potentially harbours only a few tissue cysts. In order to improve the diagnosis, ...
journal_title：European journal of protistology
pub_type： 杂志文章
doi：10.1016/j.ejop.2013.08.002
更新日期：2014-02-01 00:00:00
abstract：:Haploid micronuclei produced by meiosis in Paramecium caudatum are destined either to survive or to degenerate depending upon their position in the cytoplasm. The behavior of the four meiotic division products in living cells and their DNA synthesis patterns were examined to determine whether there were differences be...
journal_title：European journal of protistology
pub_type： 杂志文章
doi：10.1016/S0932-4739(11)80317-2
更新日期：1992-02-21 00:00:00
abstract：:A new Naegleria species, N. andersoni, is described that occurs world-wide. The new species consists of two subspecies and can be distinguished from previously described species on the basis of antigenic, isoenzyme and restriction enzyme DNA fragment differences and in maximum growth temperature tolerated. N. anderson...
journal_title：European journal of protistology
pub_type： 杂志文章
doi：10.1016/S0932-4739(88)80022-1
更新日期：1988-10-01 00:00:00
abstract：:The marine dinoflagellate Cochlodinium polykrikoides is a harmful algal bloom (HAB) species that severely impacts the environment and causes huge economic losses. Yellow clay (YC), considered to be a non-toxic and naturally-occurring material, represents an important step towards the direct control of HABs. In the pre...
journal_title：European journal of protistology
pub_type： 杂志文章
doi：10.1016/j.ejop.2019.125642
更新日期：2019-10-01 00:00:00
abstract：:The morphology of four cyrtophorian ciliates, Dysteria ovalis, D. semilunaris, Phascolodon vorticella, and Chlamydonellopsis calkinsi, were investigated using living observation and protargol-staining. The morphology of D. ovalis is revealed in detail for the first time, and it is characterized by the following combin...
journal_title：European journal of protistology
pub_type： 杂志文章
doi：10.1016/j.ejop.2016.08.005
更新日期：2016-10-01 00:00:00
abstract：:This review gives a brief report on some recent advances in the study of molecular biology of ciliate genes. The main emphasis will be put on those results which may contribute to a better understanding of how gene structure and genome organization has evolved in ciliates. New data will be discussed in relation to the...
journal_title：European journal of protistology
pub_type： 杂志文章
doi：10.1016/S0932-4739(11)80384-6
更新日期：1990-08-31 00:00:00
abstract：:We report the use of nile red as a rapid and inexpensive method to estimate cellular lipids in three species of Paramecium and in Tetrahymena by the direct application of the dye to living or fixed cells without extraction and purification. Qualitative estimates of the relative changes in the lipid content of cells of...
journal_title：European journal of protistology
pub_type： 杂志文章
doi：10.1016/S0932-4739(11)80129-X
更新日期：1990-06-29 00:00:00
abstract：:Ookinetes of Leucocytozoon simondi have a Polar Ring Complex (PRC) which is composed of a stout electron-lucent polar ring with about 34 posteriorly extending tines. The latter are subtended by about 76 subpellicular microtubules. A broad collar of electron-dense material is associated with the cytoplasmic surface of ...
journal_title：European journal of protistology
pub_type： 杂志文章
doi：10.1016/S0932-4739(89)80061-6
更新日期：1989-04-14 00:00:00
abstract：:The free-living ciliates of the order Metopida Jankowski, 1980 are pivotal players in the microbial food web of the sulfuretum, acting as hosts to prokaryotic endo- and ectosymbionts. They are also of interest in the study of the function and evolution of their mitochondrion-related organelle, the hydrogenosome. The t...
journal_title：European journal of protistology
pub_type： 杂志文章
doi：10.1016/j.ejop.2017.07.003
更新日期：2017-10-01 00:00:00
abstract：:Apostome ciliates from crayfish and freshwater shrimp in southern and central Alabama were surveyed in this study. Hyalophysa bradburyae was found on both crayfish and shrimp from 16 sites in eight drainages. A new species, Hyalophysa clampi n. sp., was found infesting crayfish at one site and simultaneously infesting...
journal_title：European journal of protistology
pub_type： 杂志文章
doi：10.1016/j.ejop.2011.11.005
更新日期：2012-08-01 00:00:00
abstract：:Differences in gel electrophoretic mobility were used to compare tubulin subunits from a variety of distantly related ciliate species. The relative electrophoretic mobility of ciliate tubulins is shown to vary depending upon the electrophoretic conditions used to separate them. Tubulin migration is altered by changing...
journal_title：European journal of protistology
pub_type： 杂志文章
doi：10.1016/S0932-4739(11)80271-3
更新日期：1993-05-28 00:00:00
abstract：:A strain of the free-living flagellate Dimastigella trypaniformis Sandon was isolated from the gut contents of the Australian termite Mastotermes darwiniensis Froggatt. The fine structure of the isolate (Ulm strain) was compared with a strain isolated from soil in Scotland (Glasgow strain). The biflagellated trophozoi...
journal_title：European journal of protistology
pub_type： 杂志文章
doi：10.1016/S0932-4739(11)80404-9
更新日期：1993-11-12 00:00:00
abstract：:Protistan parasites have an undisputed global health impact. However, outside of a few key exceptions, e.g. the agent of malaria, most of these infectious agents are neglected as important health threats. The Symposium entitled "Free-living amoebae and neglected pathogenic protozoa: health emergency signals?" held at ...
journal_title：European journal of protistology
pub_type： 杂志文章
doi：10.1016/j.ejop.2020.125760
更新日期：2020-11-28 00:00:00
abstract：:Shifts in community composition of soil protozoa in response to climate change may substantially influence microbial activity and thereby decomposition processes. However, effects of climate and vegetation on soil protozoa remain poorly understood. We studied the distribution of soil testate amoebae in herbaceous and ...
journal_title：European journal of protistology
pub_type： 杂志文章
doi：10.1016/j.ejop.2012.08.004
更新日期：2013-05-01 00:00:00
abstract：: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 definitel...
journal_title：European journal of protistology
pub_type： 杂志文章
doi：10.1016/j.ejop.2018.09.002
更新日期：2018-10-01 00:00:00
abstract：:The morphology and infraciliature of two pleurostomatid ciliates, Amphileptus aeschtae nov. spec. and Amphileptus eigneri nov. spec., collected from shrimp-culturing ponds of the Bohai Sea, China, were investigated using live observations and the protargol impregnation method. The new species A. aeschtae is identified...
journal_title：European journal of protistology
pub_type： 杂志文章
doi：10.1016/j.ejop.2006.10.002
更新日期：2007-06-01 00:00:00
