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1.
We describe the morphology and 18S rDNA phylogeny of Bryophryoides ocellatus n. g., n. sp., a bryophryid ciliate inhabiting in situ soil percolates from Idaho, U.S.A. The new genus is distinguished from other bryophryid genera by a combination of the following features: (1) kreyellid (irregularly meshed) silverline pattern, (2) polymorphic adoral organelles in the preoral suture, (3) absence of vestibular kineties. In phylogenetic analyses, Bryophryoides ocellatus is most closely related to Bryophrya gemmea. The 18S rDNA sequence pairwise distance of 2% between these genera, while similar to that between many colpodidan species, exceeds that between some colpodidan genera (e.g. Mykophagophrys and Pseudoplatyophrya, 1.1%), further supporting establishment of the new genus. Topology hypothesis testing strongly supports the monophyly of the Colpodida including the bryophryids. Despite weak nodal support, tests of topology constraints narrowly reject the non-monophyly of the sequenced Bryophryidae (Bryophrya + Bryophryoides + Notoxoma). Likewise, the monophyletic origin of the sequenced Bryophryidae is indicated in the phylogenetic networks though with low support.  相似文献   

2.
Sun P  Clamp J  Xu D  Kusuoka Y  Miao W 《Protist》2012,163(1):129-142
Recent phylogenetic analyses of the peritrich genus Vorticella have suggested that it might be paraphyletic, with one Vorticella species - Vorticella microstoma grouping with the swimming peritrichs Astylozoon and Opisthonecta in a distant clade. These results were based on very limited taxon sampling and thus could not be accepted as conclusive evidence for revising the generic classification. We tested paraphyly of the genus Vorticella by making a new analysis with a broad range of samples from three continents that yielded 52 new sequences of the gene coding for small subunit rRNA. Our results, together with the available sequences in Genbank, form a comprehensive set of data for the genus Vorticella. Analyses of these data showed that Vorticella microstoma morphotypes, Astylozoon, and Opisthonecta form a well-supported, monophyletic clade, that is distinct from and basal to the family Vorticellidae containing other species of Vorticella. Paraphyly of the genus Vorticella and family Vorticellidae was strongly confirmed by these results. Furthermore, the two clades of Vorticella identified by the SSU rRNA gene are so genetically diverse whereas the genetic distances within the one containing Vorticella microstoma morphotypes, Astylozoon, and Opisthonecta were so slight, which marked it as a separate family that must be defined by molecular characters in the absence of unifying morphological and morphogenetic characters. An emended characterization and status of the genus Vorticella, the families Vorticellidae and Astylozoidae are presented and discussed.  相似文献   

3.
ABSTRACT. Sandmanniella terricola n. g., n. sp. was discovered in soil from the Chobe floodplain, Botswana, southern Africa. Its morphology and 18S rDNA gene sequence were studied with standard methods. Sandmanniella terricola is very likely an adversity strategist because it reaches peak abundances 6–12 h after rewetting the soil and maintains trophic food vacuoles with undigested bacteria in the resting cyst, a highly specific feature suggested as an indicator for an adversity life strategy. Possibly, the energy of the stored food vacuoles is used for reproduction and support of the cyst wall. Morphologically, Sandmanniella terricola is inconspicuous, having a size of only 50 × 40 μm and a simple, ellipsoidal shape. The main characteristics of the genus are a colpodid silverline pattern; a perioral cilia condensation; a flat, dish-shaped oral cavity, in the centre of which originates a long, conical oral basket resembling that of certain nassulid ciliates; and a vertically oriented left oral polykinetid composed of brick-shaped adoral organelles. This unique mixture of features and the gene sequence trees, where Sandmanniella shows an isolated position, suggest establishing a new family, the Sandmanniellidae n. fam., possibly related to the families Colpodidae or Bryophryidae. The curious oral basket provides some support for the hypothesis of a common ancestor of colpodid and nassulid ciliates.  相似文献   

4.
Morphological data from life, protargol impregnation, and scanning electron microscopy were combined with genetic data not only to describe the marine plankton ciliates Pelagostrobilidium neptuni (Montagnes and Taylor, 1994) Petz, Song, and Wilbert, 1995 and Strombidium biarmatum nov. spec., but also to elucidate their phylogenetic relationships. Additionally, the ontogenesis of P. neptuni was studied and the diagnosis of the genus Pelagostrobilidium was improved due to further data from the newly affiliated species P. epacrum (Lynn and Montagnes, 1988) nov. comb. (basionym: Strobilidium epacrum Lynn and Montagnes, 1988). The phylogenetic analysis of the small subunit ribosomal RNA genes matched the morphologic and ontogenetic assigning of P. neptuni to the choreotrichid family Strobilidiidae. The considerable genetic distance of d = 0.074 between P. neptuni and Strobilidium caudatum corroborated the morphological differences and thus the maintenance of the genus Pelagostrobilidium. Strombidium biarmatum nov. spec. is a typical member of the genus, except for the two types of extrusomes ("trichites"): ~12 × 0.5 μm, needle-shaped ones attached anterior to the girdle kinety and ~6 × 0.5 μm, rod-shaped ones at the distal end of the intermembranellar ridges. Its flask-shaped resting cysts have several strong spines. In accordance with the morphologic data, S. biarmatum is placed within the order Oligotrichida by gene sequence analysis. The great genetic distances within the oligotrichids support the diversity found in morphologic and ontogenetic studies.  相似文献   

5.
6.
Morphology, ontogeny and the molecular phylogeny of Agolohymena aspidocauda nov. gen., nov. spec., a new freshwater tetrahymenid ciliate from Idaho, U.S.A, are described. The ontogeny and histophagous mode of nutrition are similar to those of Deltopylum rhabdoides Fauré-Fremiet and Mugard, 1946. The new genus is placed with Deltopylum in the resurrected family Deltopylidae Song and Wilbert, 1989. We emend the diagnostic features of the family to include division by polytomy, right and left somatic kineties extending into the preoral suture, crook-shaped or sigmoid adoral membranelles 1 and 2, markedly reduced adoral membranelle 3 and a tetrahymenid silverline pattern. The main diagnostic features of the new genus are a disc-shaped caudal ciliary array and formation of two types of resting cysts, one smooth and the other bearing tangled tubular or cylindrical lepidosomes. Nuclear small subunit ribosomal RNA gene and mitochondrial cytochrome oxidase subunit 1 gene sequences place the new genus basal within the order Tetrahymenida, well separated from members of the family Tetrahymenidae (Lambornella and Tetrahymena) and also from other tetrahymenids (Colpidium, Dexiostoma, Glaucoma). The genetic divergences between this species and other genera in Tetrahymenida are large enough to suggest placement of the new genus in a separate family. This corroborates the morphological data, since the elaborate caudal ciliary array and the lepidosome-covered resting cyst of this species are not found in other Tetrahymenidae.  相似文献   

7.
Using 11 new SSU-rDNA sequences, we analyze relationships within the class Colpodea, especially of some uncommon taxa, such as Kalometopia duplicata, Cyrtolophosis minor, and Jaroschia sumptuosa. The sequences do not change the basic structure of the molecular Colpodea tree, i.e., all belong to one of the four molecular clades recognized by Foissner et al. (2011): Colpodida, Cyrtolophosidida, Bursariomorphida, and Platyophryida. The addition of three Colpoda sequences strengthens the observation that species of this genus are distributed over the whole molecular Colpodea tree. Very likely, this is caused by a fast radiation of Colpoda, several species of which then evolved independently, forming new genera and families. Cyrtolophosis minor, which belongs to the molecular Pseudocyrtolophosis clade, is referred to a new genus, Apocyrtolophosis nov. gen., characterized by a comparably large, deltoid oral opening, an unciliated posterior region, and the absence of an oblique kinety in the left oral polykinetid. Bryometopus triquetrus does not erase the paraphyly of its genus. Platyophrya vorax, P. spumacola, and P. bromelicola form a highly supported clade in the order Platyophryida. Platyophryides and Ottowphrya are close genetically but differ in the silverline pattern (colpodid vs. platyophryid).  相似文献   

8.
9.
A new species of the holopodid genus Cyathidium was found on rocks off Grande Comore in a depth of around 200 m. Based on external morphology of resting animals, the new species Cyathidium plantei sp. n is described, with emphasis on comparison to the only other extant species ( C. foresti ) as well as to the four extinct representatives of the genus. Concerning morphological characters, the new species is almost identical to the Cretaceous C. depressum . A cladistic analysis of the entire family, including the genus Holopus, shares a peculiar pattern of bending of the arms, which in principle is an apomorphic character of the family and in detail shows variations within the family. In addition, stratigraphic data are used for the determination of the evolutionary direction. This analysis reveals that the two recent species are closely related to each other, and to the fossil C. depressum . from which the entire family is probably derived.  相似文献   

10.
The neotropical genus Fosterella L.B. Smith (Pitcairnioideae, Bromeliaceae) comprises about 30 species, with a centre of diversity in semiarid to humid habitats of the Andean slopes and valleys of Bolivia. Morphologic differentiation of species is difficult because of a paucity of diagnostic characters, and little is known about the infrageneric phylogeny. Here, we present the results of an amplified fragment length polymorphism (AFLP) analysis of 77 Fosterella specimens, covering 18 recognized species and 9 as-yet undescribed morphospecies. Eight primer combinations produced 310 bands, which were scored as presence/absence characters. Neighbour-joining tree reconstruction revealed 12 clusters (A-L) with various levels of support. Well-supported species groups were also recovered by a principal coordinates analysis. With few exceptions, morphologically defined species boundaries were confirmed by the molecular data. Phylogenetic relationships between species groups remained ambiguous, however, because of short internal branch lengths. The AFLP data were complemented by a survey of the leaf anatomy of 19 Fosterella species. Species concepts and assemblages are discussed in the context of molecular, morphologic, anatomic, ecologic, and biogeographic data. The data suggest that accidental long-distance dispersal and founder events have been important for Fosterella speciation.  相似文献   

11.
12.
A new colpodid ciliate, Bresslauides pratensis n. sp., was discovered in soil from a meadow field in Turkey. Its morphology was investigated using live observation, protargol impregnation, silver nitrate impregnation, and scanning electron microscopy. The new species differs from the congeners by the following combination of features: the cell size in vivo is about 135-180 μm × 130-160 μm; the body has an almost circular outline with a conspicuous bulge on the ventral side; the somatic cilia are arranged in about 105 densely spaced, sigmoidal kineties; a diagonal groove extends to the left cell side, terminating in a pronounced postoral sack; one almost globular macronucleus and usually two globular micronuclei; the oral structures occupy almost the anterior half of the cell and comprise a distally elongated right polykinetid and a crescentic left oral polykinetid, both restricted to the vestibulum; on average 12 vestibular, 31 postoral, and 55 left oral kineties. Based on the morphological data, it was concluded that B. pratensis is a well-outlined and distinctive member of the genus Bresslauides. Additionally, the most recent molecular data on the order Colpodida and genera Colpoda, Bresslaua, and Bresslauides are briefly discussed.  相似文献   

13.
Based on a complex analysis of both morphological and molecular genetic data, a new subfamily of casebearer moths, Omphalopodinae subfam. n., is allocated. Omphalopoda Falkovitsh, 1987, the type genus of this subfamily, is well distinguished by a set of apomorphic morphological characters and is clearly clustered between two genetically well differentiated groups of the family Coleophoridae: Tolleophorinae and Coleophorinae + Augasminae + Ischnophaninae + Metriotinae.  相似文献   

14.
The systematics of Leptotyphlopidae is historically controversial mostly due to their conserved external morphology in comparison with other snakes. However, recent studies have stressed that anatomical data might be informative for clarifying the leptotyphlopid taxonomy and evolution. We erect a new genus to accommodate Leptotyphlops collaris based on evidence from osteology, hemipenial morphology, and molecular data. We also provide expanded data regarding the intraspecific variation based on additional specimens collected in field trips and literature data, performing detailed comparisons among the new genus and all other New World leptotyphlopids. The new genus is distinguished from other leptotyphlopids by its unique hemipenial morphology and its exclusive combination of osteological and external morphology characters, with molecular data also supporting the new generic arrangement. We also provide a comprehensive discussion of the hemipenial morphology for the subfamily Epictinae based on literature and novel data gathered herein.  相似文献   

15.
A new genus belonging to the family Microcharmidae is described from the northern range of Madagascar. The new genus appears as a possible link between the Microcharmidae and the Buthidae within the Buthoidea. Phylogenetic considerations are proposed in relation to the observed morphological characters.  相似文献   

16.
Jordal BH 《ZooKeys》2010,(56):141-156
The genus Phloeoditica Schedl currently includes four species from Southeast Asia. These species vary substantially in important morphological characters and indicate the existence of multiple genera for these species. A revision based on morphological and in part molecular data resulted in the transfer of Phloeoditica setosa to Pseudoxylechinus the erection of a new genus Asiophilus for Phloeoditica phloeosinoides and a new species Asiophilus macropunctatus from Vietnam. Another new genus with affinities to Phloeoditica is described based on the new species Microditica uniseriata from Thailand. The new genera are included in a revised key to the tribe Phloeosinini.  相似文献   

17.
The morphology, morphogenesis, and phylogeny of an undescribed oligotrich sensu lato (s. lat.) ciliate, Lynnella semiglobulosa n. g., n. sp., found in Daya Bay, southern China, were investigated. This species shares some features with both oligotrichs sensu stricto and choreotrichs, but most morphological and morphogenetic characters as well as the phylogenetic analysis suggest that it should be assigned into subclass Choreotrichia temporarily. Lynnella semiglobulosa is distinguished from members of all known genera and families of the subclass Choreotrichia by a unique combination of characteristics of the buccal and somatic ciliatures. Thus, a new family Lynnellidae n. fam. and a new genus Lynnella n. g. are proposed for it. The new family is distinguished by an open adoral zone of membranelles (AZM) in which, however, there are no ventral membranelles; the distal and proximal portions of the new adoral zone lie close to each other forming an open circle in stomatogenesis. The new genus Lynnella is characterized by possessing two longitudinally oriented somatic kineties, one dorsal and one ventral, several proximal membranelles progressively lengthened toward the proximal end of adoral zone, and two macronuclear nodules. In phylogenetic analyses based on small subunit rRNA gene sequences, L. semiglobulosa clustered basally to all choreotrichs, but with relatively weak support; nevertheless, the possibility of a relationship with the subclass Oligotrichia was not rejected by the approximately unbiased nor Shimodaira-Hasegawa test. Based on morphological, morphogenetic, and molecular evidence of L. semiglobulosa, it is confirmed that the open AZM should be a plesiomorphic character of oligotrichs s. lat. as suggested previously.  相似文献   

18.
Chi  Yong  Chen  Xiangrui  Li  Yuqing  Wang  Chundi  Zhang  Tengteng  Ayoub  Alex  Warren  Alan  Song  Weibo  Wang  Yuanyuan 《中国科学:生命科学英文版》2021,64(4):606-620
Heterotrichous ciliates play an important role in aquatic ecosystem energy flow processes and many are model organisms for research in cytology, regenerative biology, and toxicology. In the present study, we combine both morphological and molecular data to infer phylogenetic relationships at family-genus level and propose new evolutionary hypotheses for the class Heterotrichea. The main results include:(1) 96 new ribosomal DNA sequences from 36 populations, representing eight families and 13 genera, including three poorly annotated genera, Folliculinopsis, Ampullofolliculina and Linostomella;(2) the earliest-branching families are Spirostomidae in single-gene trees and Peritromidae in the concatenated tree, but the family Peritromidae probably represents the basal lineage based on its possession of many "primitive" morphological characters;(3) some findings in molecular trees are not supported by morphological evidence, such as the family Blepharismidae is one of the most recent branches and the relationship between Fabreidae and Folliculinidae is very close;(4) the systematic positions of Condylostomatidae, Climacostomidae, and Gruberiidae remain uncertain based either on morphological or molecular data; and(5)the monophyly of each genus included in the present study is supported by the molecular phylogenetic trees, except for Blepharisma in the SSU r DNA tree and Folliculina in the ITS1-5.8 S-ITS2 tree.  相似文献   

19.
20.
A new genus Simplicaris (Copepoda, Harpacticoida, Parastenocarididae) is established to accommodate two species collected from deep groundwater in Italy, S. lethaea sp. nov. and S. veneris (Cottarelli & Maiolini, 1980) comb. nov. Parastenocaris hippuris Hertzog, 1938 and P. aedes Hertzog, 1938 are ranked as incertae sedis within the genus. Members display complete absence of leg 5 in both sexes and an unusual elongation of the first exopodal segments of legs 1–4, in which exp-1 is distinctly longer than exp-2 or -3, or as long as exp-2 and -3 combined. As the systematic status of the family Parastenocarididae and of the type genus Parastenocaris is still in flux, a list of phylogenetically informative characters is proposed, along with a discussion of their various states in representative members of the family. The genus Parastenocaris sensu stricto is redefined to comprise only the brevipes -group. The remaining members of the genus are considered Parastenocaris sensu lato pending a thorough revision of the family.  © 2004 The Linnean Society of London, Zoological Journal of the Linnean Society , 2004, 140 , 417−436.  相似文献   

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