Small-subunit rRNA gene sequences from representatives of selected families of the Gigartinales and Rhodymeniales (Rhodophyta). 2. Recognition of the Halymeniales ord.nov.

1996 ◽  
Vol 74 (5) ◽  
pp. 694-707 ◽  
Author(s):  
G. W. Saunders ◽  
G. T. Kraft

Nucleotide sequences of the nuclear, small-subunit ribosomal RNAs, as inferred from polymerase chain reaction amplified products, are introduced for representatives of the Dumontiaceae, Endocladiaceae, Halymeniaceae, and Kallymeniaceae of the order Cryptonemiales sensu Kylin, the Mychodeaceae, Phyllophoraceae, Schizymeniaceae, and Sebdeniaceae of the order Gigartinales sensu Kylin, and the Lomentariaceae and Rhodymeniaceae of the order Rhodymeniales. The new sequences are included in phylogenetic analyses incorporating previously published sequences from additional families of the orders Ahnfeltiales, Ceramiales, Gigartinales, Gracilariales, Palmariales, Plocamiales, and Rhodymeniales. We used the molecular data to test the validity of the taxonomic merger of the orders Gigartinales and Cryptonemiales that was proposed by G.T. Kraft and P.A. Robins in 1985. With only two exceptions (the families Halymeniaceae and Sebdeniaceae), phylogenetic analyses of the SSU data support a monophyletic origin for a combined Gigartinales–Cryptonemiales. We therefore propose the resurrection of a redefined Cryptonemiales to consist, at this time, of only the Halymeniaceae and Sebdeniaceae. Because virtually no elements of the original or recent definitions of the Cryptonemiales survive in the characterization of this taxon, we followed procedures allowed by the International Code of Botanical Nomenclature to designate it the Halymeniales ord.nov. Analysis of molecular data further indicates that the Rhodymeniales is a monophyletic assemblage distinct from both the Gigartinales and Halymeniales; it should not be merged with the Gigartinales as is occasionally suggested. Keywords: Cryptonemiales, Gigartinales, Halymeniaceae, Halymeniales, phylogeny, Rhodophyta, Sebdeniaceae, small-subunit rRNA, systematics.

1994 ◽  
Vol 72 (9) ◽  
pp. 1250-1263 ◽  
Author(s):  
G. W. Saunders ◽  
G. T. Kraft

Nucleotide sequences of the nuclear, small-subunit (SSU) ribosomal RNAs, as inferred from polymerase chain reaction (PCR)-amplified products, are presented for Areschougia congesta (Turner) J. Agardh (Solieriaceae), Dasyphloea insignis Montagne (Dumontiaceae), Sarcothalia crassifolia (C. Agardh) Edyvane & Womersley (Gigartinaceae), Nizymenia australis Sonder (Nizymeniaceae), Phacelocarpus peperocarpos (Poiret) Wynne, Ardré & Silva (Phacelocarpaceae), Plocamiocolax pulvinata Setchell, Plocamium angustum (J. Agardh) J.D. Hooker, Plocamium cartilagineum (Linnaeus) Dixon (Plocamiaceae), Rhodymenia linearis J. Agardh (Rhodymeniaceae), and Sphaerococcus coronopifolius Stackhouse (Sphaerococcaceae). Phylogenetic analyses of the SSU sequences between the Plocamiaceae and members of the Sphaerococcaceae, Phacelocarpaceae, and Nizymeniaceae, with which the Plocamiaceae has been associated historically, show SSU differences of between 87 and 105 nucleotides and do not indicate a close relationship. A review of anatomical knowledge of the Plocamiaceae and Pseudoanemoniaceae and new information on vegetative and tetrasporangial development in Plocamium and Plocamiocolax are presented to buttress a case for the Plocamiales ord.nov. Representatives of the Nizymeniaceae and Phacelocarpaceae differ from one another by only nine nucleotides, suggesting that these two taxa are very closely related and perhaps not distinct at the family rank. Key words: Gigartinales, PCR, phylogeny, Plocamiales ord.nov., Pseudoanemoniaceae, Rhodophyta, small-subunit rRNA, systematics.


2010 ◽  
Vol 60 (2) ◽  
pp. 460-468 ◽  
Author(s):  
Miao Miao ◽  
Yangang Wang ◽  
Weibo Song ◽  
John C. Clamp ◽  
Khaled A. S. Al-Rasheid

Recently, an undescribed marine ciliate was isolated from China. Investigation of its morphology and infraciliature revealed it as an undescribed species representing a new genus, Eurystomatella n. gen., the type of the new family Eurystomatellidae n. fam. The new family is defined by close-set, apically positioned oral membranelles and a dominant buccal field that is surrounded by an almost completely circular paroral membrane. The new genus is defined by having a small oral membranelle 1 (M1), bipartite M2 and well-developed M3, a body surface faintly sculptured with a silverline system in a quadrangular, reticulate pattern and a cytostome located at the anterior third of a large buccal field. The type species of the new genus, Eurystomatella sinica n. sp., is a morphologically unique form that is defined mainly by the combination of a conspicuously flattened body, several caudal cilia, extremely long cilia associated with the buccal apparatus and a contractile vacuole located subcaudally. According to phylogenetic analyses of small-subunit (SSU) rRNA gene sequences, Eurystomatella clusters with the genus Cyclidium, as a sister group to the family Pleuronematidae. The great divergence in both buccal and somatic ciliature between Eurystomatella and all other known scuticociliates supports the establishment of a new family for Eurystomatella.


Zootaxa ◽  
2009 ◽  
Vol 2005 (1) ◽  
pp. 57-66 ◽  
Author(s):  
WEIWEI LIU ◽  
JIQIU LI ◽  
SHAN GAO ◽  
CHEN SHAO ◽  
JUN GONG ◽  
...  

The morphology of a new marine urostylid ciliate, Apokeronopsis sinica n. sp., collected from the Clear Water Bay, Hong Kong, was investigated. Additionally, the SSrRNA gene was sequenced in order to make a comparison at molecular level. Based on both morphological and molecular data, descriptions and comparisons with its congeners are provided. Apokeronopsis sinica is characterized by: body size about 150–200 × 50–65 µm in vivo; two kinds of cortical granules; about 20 cirri in frontal area which form the non-typical bicorona; 2 frontoterminal, ca. 4 buccal and 10 transverse cirri; midventral complex consists of 21–32 pairs of cirri; on average 35 right and 30 left marginal cirri; about 50 membranelles; invariably 3 dorsal kineties. A key to the identification of the known Apokeronopsis species was suggested. The small subunit rRNA gene sequence differences between Apokeronopsis sinica and its congeners range from 1.64% to 3.72%.


2013 ◽  
Vol 63 (Pt_9) ◽  
pp. 3506-3514 ◽  
Author(s):  
Ying Yan ◽  
Yuan Xu ◽  
Zhenzhen Yi ◽  
Alan Warren

Three trachelocercid ciliates, Kovalevaia sulcata (Kovaleva, 1966) Foissner, 1997, Trachelocerca sagitta (Müller, 1786) Ehrenberg, 1840 and Trachelocerca ditis (Wright, 1982) Foissner, 1996, isolated from two coastal habitats at Qingdao, China, were investigated using live observation and silver impregnation methods. Data on their infraciliature and morphology are supplied. The small subunit rRNA (SSU rRNA) genes of K. sulcata and Trachelocerca sagitta were sequenced for the first time. Phylogenetic analyses based on SSU rRNA gene sequence data indicate that both organisms, and the previously sequenced Trachelocerca ditis, are located within the trachelocercid assemblage and that K. sulcata is sister to an unidentified taxon forming a clade that is basal to the core trachelocercids.


2011 ◽  
Vol 61 (7) ◽  
pp. 1740-1750 ◽  
Author(s):  
Yangang Wang ◽  
Xiaozhong Hu ◽  
Jie Huang ◽  
Khaled A. S. Al-Rasheid ◽  
Alan Warren

Two marine stichotrich ciliates, Metaurostylopsis flavicana spec. nov. and Tunicothrix wilberti (Lin & Song, 2004) Xu et al., 2006, isolated from the Shenzhen Mangrove Protection Area on the coast of the South China Sea, were investigated using live observation and protargol impregnation techniques. Metaurostylopsis flavicana is characterized by its elongate body shape, yellowish body colour and bright-yellow cortical granules that are either grouped around the cirri and the dorsal cilia or aligned between the rows of cirri and dorsal cilia. It has four to eight frontal, two frontoterminal, one buccal and seven to ten transverse cirri, a mid-ventral complex comprising 13–17 midventral cirral pairs in a row that extends about three-fifths of the body length, four left and three right marginal rows and three complete dorsal kineties. The small subunit rRNA gene of this species was sequenced and phylogenetic trees were constructed in which M. flavicana does not group with its congeners, suggesting that the genus Metaurostylopsis is paraphyletic. Some supplementary morphological and morphogenetic traits for Tunicothrix wilberti are also documented.


Author(s):  
O. Tirado ◽  
W. Rosado ◽  
N.S. Govind

Several bacteria have been isolated from different tropical ecosystems (tropical rain forest, seawater, and marine sediments) from the island of Puerto Rico. These microorganisms were screened for carbohydrase activity using chromogenic substrates (amylose, pullulan, cellulose, dextran, arabinan, galactomannan, and xylan). The results indicate that 2–9% of cultured organisms show carbohydrase activity. Isolates were identified by partial sequence analysis of the polymerase chain reaction amplified small subunit rRNA gene. GenBank database comparison of the most versatile strains gave a match with Bacillus sp., Staphylococcus sp., Halomonas sp., and a gamma proteobacterium. Growth curves indicate that all strains assayed can grow as well in at least one complex carbohydrate as in glucose. A high β-xylosidase activity was detected in the Bacillus sp. strain crude enzyme preparation and this activity seems to be almost entirely cell associated. Our results show that tropical environments can be potentially good sources of bacteria with novel carbohydrases.


2013 ◽  
Vol 63 (Pt_3) ◽  
pp. 1155-1164 ◽  
Author(s):  
Xumiao Chen ◽  
Miao Miao ◽  
Honggang Ma ◽  
Chen Shao ◽  
Khaled A. S. Al-Rasheid

A novel stichotrich ciliate, Strongylidium orientale sp. nov., was discovered from a mangrove river in Hong Kong, southern China, and its morphology was investigated through observations in vivo and after protargol impregnation. Cells are 80–120×35–50 µm in vivo and fusiform in shape, with rounded anterior and tapered posterior ends. It is characterized by its brackish habitat and by the presence of two types of cortical granules arranged irregularly throughout the cortex. Morphogenetic events of cell division and physiological reorganization are described. The main ontogenetic features were: (i) only the posterior portion of the parental adoral zone of membranelles was renewed by dedifferentiation of the old structures; (ii) the oral primordium in the opisthe occurred apokinetally; (iii) the left and right ventral rows originated intrakinetally and the final left ventral row was spliced from two cirri from the frontoventral cirral anlage, a short cirral row from the anlage for the right ventral row and a long cirral row which was formed from the whole anlage of the left ventral row; (iv) the marginal rows developed intrakinetally; (v) the dorsal kineties replicated entirely de novo and did not fragment; and (vi) the two macronuclear nodules fused into a mass and then divided. Based on small-subunit rRNA gene sequences, phylogenetic analyses showed a close relationship with its congener Strongylidium pseudocrassum and with the genus Pseudouroleptus.


Author(s):  
Andrew J. Gooday ◽  
Jan Pawlowski

Conqueria laevis gen. and sp. nov., a new monothalamous agglutinated foraminiferan, is described from core samples collected in the abyssal western Weddell Sea. The species is characterized by a very elongate, almost cylindrical test that usually follows a more or less curved course and has a single terminal aperture located at the end of a short neck. The wall has a very smooth outer surface and is composed of tiny (<5 μm) agglutinated particles. Very similar and presumably congeneric morphotypes occur at northern hemisphere sites, including Arctic fjords around Svalbard and the Porcupine Abyssal Plain. Molecular phylogenetic analyses, based on small subunit rRNA gene sequences, indicate that the new Weddell Sea species forms an independent lineage branching among monothalamous foraminiferans as a sister group to the clade of Psammophaga.


2013 ◽  
Vol 63 (Pt_9) ◽  
pp. 3515-3523 ◽  
Author(s):  
Xuming Pan ◽  
Mingzhuang Zhu ◽  
Honggang Ma ◽  
Khaled A. S. Al-Rasheid ◽  
Xiaozhong Hu

The morphology and infraciliature of two novel marine scuticociliates, Metanophrys orientalis spec. nov. and Uronemella sinensis spec. nov., collected from sandy beaches at Qingdao, China, were investigated using live observation and protargol-staining methods. Metanophrys orientalis spec. nov. is distinguished by the following characteristics: marine habitat and a slender to elongate oval body with pointed anterior end and rounded caudal end, in vivo about 25–50 µm long; buccal field about a quarter to a third of body length; nine or ten somatic kineties with dikinetids approximately in anterior half of body, monokinetids in posterior half; membranelles 1 and 2 almost equal in length and composed of two and three longitudinal rows of kinetids respectively; paroral membrane with zigzag structure extending anteriorly to middle portion of membranelle 2; contractile vacuole pore located at posterior end of somatic kinety 1. The genus Uronemella is redefined as follows: marine form with an elongate-elliptical or inverted pear-shaped body; apical plate conspicuous; buccal field about two-thirds of body length, cytostome subequatorially located; oral apparatus Uronema-like; somatic kineties comprising a mixture of dikinetids and monokinetids. Uronemella sinensis spec. nov. is recognized by having an elongate-elliptical body with truncated apical frontal plate, size in vivo about 25–35×15–20 µm, nine or ten somatic kineties, membranelle 1 consisting of two or three basal bodies, contractile vacuole pore at posterior end of somatic kinety 1. This study also compared the small-subunit rRNA gene sequences of these two species with other closely related species to show the sequence divergence, which ranged from 3.53 to 9.60 %. Phylogenetic analyses support the contention that the genus Uronemella is monophyletic, while Metanophrys is non-monophyletic.


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