Showing papers by "Saleh A. Al-Farraj published in 2008"
TL;DR: It was concluded that planktonic protists are potentially useful bioindicators of water quality in a semi-enclosed mariculture system and were strongly correlated with water temperature and abundances of bacteria.
Abstract: In order to evaluate the environmental status within a mariculture pond, temporal variations of physico-chemical factors, protist community structure and interactions between biota and environmental conditions were investigated during a complete cycle in semi-enclosed shrimp-farming waters near Qingdao, north China. Results revealed that: (1) a total of 54 protist taxa with ten dominant species was present, comprising 4 chlorophyceans, 2 chrysophyceans, 5 cryptophyceans, 10 dinoflagellates, 3 euglenophyceans, 10 diatoms, 18 ciliates and 2 sarcodines; (2) a single peak of protist abundance occurred in October, mainly due to the chlorophyceans, diatoms and chrysophyceans, while the bimodal peaks of biomass in July and October were mainly due to the ciliates, dinoflagellates and diatoms; (3) the succession of protist communities significantly correlated with the changes of nutrients, salinity and temperature, especially phosphate, either alone or in combination with NO3; (4) species diversity and evenness indices were found to be relatively independent of physico-chemical factors, whereas species richness and the ratio of biomass to abundance were strongly correlated with water temperature and abundances of bacteria. It was concluded that planktonic protists are potentially useful bioindicators of water quality in a semi-enclosed mariculture system.
72 citations
TL;DR: The present study supports the conclusion reported by previous researchers that urostylids could be a paraphyletic assemblage and that Uroleptus and Paruroleptus should be removed from the order Urostylida and a new suborder Parabirojimina n.
55 citations
TL;DR: The morphology, infraciliature and silverline system of two marine scuticociliates isolated from the sand beaches along the coast of Qingdao, China, were investigated using live observation and silver impregnation methods and it is proposed that three nominal forms should be synonymized with P. coronatum.
27 citations
TL;DR: The morphology and infraciliature of two new marine urostylid ciliates, Metaurostylopsis struederkypkeae n.
Abstract: The morphology and infraciliature of two new marine urostylid ciliates, Metaurostylopsis struederkypkeae n. sp. and Thigmokeronopsis stoecki n. sp., collected from the coastal waters off Qingdao (Tsingtao), China, have been investigated. Metaurostylopsis struederkypkeae n. sp. is characterized by the slender body shape, small size, rose-reddish cell colour, and having two kinds of pigment-like granules. The larger pigment-like granules are yellow-green or grass-green in colour, oval in shape, and flattened, whereas the smaller ones are wine-reddish. Infraciliature and nuclear apparatus are similar to the well-known Metaurostylopsis marina. Thigmokeronopsis stoecki n. sp. is characterized by its large size with dark brown cell colour and grass-green cortical granules, which are large, blood-cell shaped, and sparsely distributed. The thigmotactic ciliature is conspicuous: 11-14 rows of densely arranged cirri occupy the most postoral area. Keys are provided for all the known species in both genera.
23 citations
TL;DR: The morphology and morphogenesis of a new marine hypotrich ciliate, Apokeronopsis bergeri nov. spec.
18 citations
TL;DR: The morphology and infraciliature of three marine ciliates, Frontonia didieri n.
Abstract: The morphology and infraciliature of three marine ciliates, Frontonia didieri n. sp., F. multinucleata n. sp. and F. tchibisovae, isolated from northern China seas, were investigated using living observation and silver impregnation methods. Frontonia didieri n. sp. is recognized by: in vivo ca. 100–150 × 45–80 µm; 61–71 somatic, 3 vestibular and 3–5 postoral kineties; 4-rowed peniculus 1 and 2; peniculus 3 three-rowed; contractile vacuole centrally-located, with about eight conspicuous collecting canals. Frontonia multinucleata n. sp. is characterized by: 70–120 × 40–75 µm in vivo, dorsoventrally flattened about 2:1; 58–67 somatic, 3 vestibular and 4–5 postoral kineties; 3 peniculi each with 4 kineties; 2–4 globular macronuclear nodules; contractile vacuole located in posterior 1/3 of cell length. Based on both original and the Qingdao population, the poorly-defined Frontonia tchibisovae is redefined and a new diagnosis is supplied.
18 citations
TL;DR: A key is presented to the seven clearly defined marine Loxophyllum species found in the coastal areas of north China Sea and two previously reported organisms under the name of L. helus are very likely, in the authors' opinion, misidentifications, and might be two unknown forms.
Abstract: Three highly confused Loxophyllum helus-like morphotypes (i.e. Loxophyllum rostratum Cohn, 1866, Loxophyllum sinicum n. sp., and Loxophyllum simplex Kahl, 1933) found in mariculture waters near the coast of Qingdao, China, were investigated with emphasis on their live morphology and infraciliature. Comparative descriptions of these three organisms are presented and synonyms are critically discussed. The validity of L. sinicum n. sp. is confirmed mainly by the combination of the distribution of extrusomes, features of general living morphology, morphometric data, and the characters of the somatic ciliature. Two previously reported organisms under the name of L. helus by Dragesco (1966, variety a) and by Dragesco and Dragesco-Kerneis (1986) are discussed and are believed to be synonyms of L. sinicum. Furthermore, two isolates described by Dragesco (1960) and Ozaki and Yagiu (1943) under the name of L. helus are very likely, in our opinion, misidentifications, and might be two unknown forms. In the light of the current study, a key is presented to the seven clearly defined marine Loxophyllum species found in the coastal areas of north China Sea.
16 citations
TL;DR: The cortical development of Prodiscocephalus borrori was observed during binary division and a phylogenetic tree was constructed which suggests that the discocephalines might be a divergent, or possibly an ancestral, group within the stichotrichs and separate from the euplotids.
Abstract: The Prodiscocephalus-like ciliates, or discocephalines, are cephalized organisms that are traditionally considered to be hypotrichs (sensu lato) but whose precise systematic position has long been uncertain. The main reasons for this are that these organisms exhibit several intermediate morphological and morphogenetic features and that hitherto none has been investigated using molecular methods. In the present study, the cortical development of Prodiscocephalus borrori was observed during binary division and this can be summarized as follows: (i) in the parental adoral zone of membranelles, only the posterior end is renewed by dedifferentiation of the old structures; (ii) the oral primordium in the opisthe occurs de novo on the cell surface as seen in other typical stichotrichs; (iii) in both dividers, the undulating membranes anlage does not split longitudinally in the usual way but, instead, divides transversely to form the paroral and endoral membranes; (iv) usually seven frontoventral transverse cirral anlagen are formed in the primary mode which then divide into two sets, one each for the proter and opisthe; (v) both left and right marginal rows divide into two parts, thus giving rise to a post-lateral marginal segment at the posterior end of each; (vi) invariably five caudal cirri are formed at the posterior end of the three rightmost dorsal kinety anlagen. Thus, it was found that, like other related discocephalines, P. borrori exhibits more similarities to stichotrichs than to euplotids. Based on a combination of morphological and morphogenetic data, a phylogenetic tree was constructed which suggests that the discocephalines group within the stichotrichs and separate from the euplotids. In addition, the complete small-subunit rRNA gene (SSU rDNA) of P. borrori was sequenced and analysed. In the resulting SSU rDNA tree, the discocephalines represent an intermediate group between the euplotids and the Stichotrichia-Oligotrichia-Choreotrichia assemblage, albeit with low bootstrap support. From these data, we conclude that the discocephalines might be a divergent, or possibly an ancestral, group within the Stichotrichia. Furthermore, our findings further support the suggestion that these organisms should be considered as a distinct order, i.e. Discocephalida Wicklow, 1982, in the subclass Stichotrichia Small & Lynn, 1985.
16 citations
Journal Article•
TL;DR: A new species of marine hypotrichous ciliates isolated from the northern China sea is studied using live observation and protargol impregnation, characterized by its slender, yellow-brownish body with two types of cortical granules.
Abstract: Two marine hypotrichous ciliates, Metaurostylopsis sinica nov. spec. and M. salina Lei et al. 2005, isolated from the northern China sea are studied using live observation and protargol impregnation. The new species is characterized by its slender, yellow-brownish body with two types of cortical granules. It has four frontal, two frontoterminal, one buccal and five to eight transverse cirri, 11-15 midventral cirral pairs, three left and two right marginal cirral rows and three complete dorsal kineties. The main morphogenetic features are: (1) no ventral cirral row posterior to the midventral rows is formed, and (2) the macronuclear nodules fuse into a single mass as in most urostylids. Based on the Qingdao population, additional observations for M. salina Lei et al. 2005 are documented and a redescription is provided. The small subunit rRNA genes of M. sinica and M. salina were sequenced in order to compare their similarities.
16 citations
Journal Article•
TL;DR: Two poorly defined marine euplotid ciliates from coastal waters near Qingdao (Tsingtao) northern China were investigated and improved diagnoses and morphometric data are provided for both species.
Abstract: Based on the living observation and silver impregnation methods, two poorly defined marine euplotid ciliates, Aspidisca orthopogon Deroux and Tuffrau, 1965 and Aspidisca aculeata (Ehrenberg, 1838) Kahl, 1932, from coastal waters near Qingdao (Tsingtao), northern China, were investigated. Improved diagnoses and morphometric data are provided for both species. As an additional contribution, morphogenesis in Aspidisca orthopogon during binary fission was re-examined and can be summarized as follows: 1) the parental adoral zone of membranelles and paroral membrane are retained by the proter; 2) the oral primordium of the opisthe develops hypoapokinetally in a sub-surface pouch below the posterior part of the adoral zone of membranelles; 3) five frontoventral-transverse cirral anlagen are formed de novo, initially as primary primordia, and develop into 3:3:2:3:1 cirri from left to right respectively in both dividers; 4) the leftmost frontoventral cirrus is generated from an independently formed cirral anlage in both dividers.
12 citations
TL;DR: The motile stages of the parasite recorded in the present study showed all the general architectures of the Apicomplexa with some pecularities such as presence of micronemes and rhoptries at both sides of the nucleus and the occurance of large number of subpellicular microtubules extending to the posterior end of the parasites.
Abstract: A Haemogregarine sp. infecting the Viper Cerastes cerastes gasperitti (35%) from K.S.A. was recorded for the 1st time. Parasites were recorded exclusively in the red blood cells of the Vipers. Erythrocytic parasites measured 17.5 x 3 microm with a nucleus of 8.1 x 2.5 microm. Mature Schizonts of 30 x 2.5 microm and producing 18-30 merozoites by ectomerogony were reported in the endothelial cells of blood capillaries of different internal organs (liver, spleen and lung). The merozoites measured 13 x 3.5 microm and these were similar to the stages in the red blood cells. The motile stages of the parasite recorded in the present study showed all the general architectures of the Apicomplexa with some pecularities such as presence of micronemes and rhoptries at both sides of the nucleus and the occurance of large number of subpellicular microtubules (80-90) extending to the posterior end of the parasite.
Journal Article•
TL;DR: A little-known marine hypotrich, Apokeronopsis ovalis, found in coastal waters near Qingdao, China, was investigated with emphasis on its living morphology, infraciliature and morphogenesis, and an improved diagnosis and redescriptions are supplied.
Abstract: A little-known marine hypotrich, Apokeronopsis ovalis (Kahl, 1932) nov. comb. [basionym: Holosticha (Keronopsis) ovalis Kahl, 1932], found in coastal waters near Qingdao, China, was investigated with emphasis on its living morphology, infraciliature and morphogenesis. Based on the data obtained, an improved diagnosis and redescriptions are supplied. It differs from all the congeners mainly by the body shape, colour and the distribution of two kinds of cortical granules and the morphometric as well as the molecular data. Apokeronopsis ovalis is distinct genetically (4.34%, 3.9% and 4.41% in the SSU rRNA gene sequence) from its congeners, A. crassa, A. bergeri and A. wrighti, respectively. Ontogenesis is basically similar to the pattern as revealed in congeners, which is characterized by the de novo formed oral primordium in the proter as well as the apokinetal formation of both the dorsal kinety and marginal row anlagen in both dividers. In addition, a key is provided for all known morphospecies in this genus.
TL;DR: The small subunit ribosomal RNA (SS rRNA) gene of three marine Condylostoma species was sequenced, by which the phylogenetic trees were constructed by distance-matrix, maximum parsimony and Bayesian inference methods, showing that all the trees have similar topologies with high supports.
Abstract: The systematically poorly known ciliate genus Condylostoma was erected by Vincent in 1826. About 10 morphotypes have been reported, but any molecular investigations concerning this group so far are lacking. In this work, the small subunit ribosomal RNA (SS rRNA) gene of three marine Condylostoma species was sequenced, by which the phylogenetic trees were constructed by distance-matrix, maximum parsimony and Bayesian inference methods. The results show that (1) all the trees have similar topologies with high supports; (2) Condylostoma is mostly related to the genus Condylostentor ; and (3) three Condylostoma species as well as Condylostentor auriculatus cluster together and form a sister group with other heterotrichs. This is moderately consistent with the assessment of phylogenetic relationships of Condylostoma -related heterotrichs from the morphological information. The phylogenetic relationship of some other related heterotrichs, Peritromus, Folliculina, Stentor and Blepharisma , has been also discussed.
Journal Article•
TL;DR: Two poorly known marine suctorian ciliates, Ephelota truncata Fraipont and E. mammillata Dons, collected from the coastal waters off Qingdao, China, were investigated using both live observations and protargol impregation methods.
Abstract: Summary. Two poorly known marine suctorian ciliates, Ephelota truncata Fraipont, 1878 and Ephelota mammillata Dons, 1918, collected from the coastal waters off Qingdao, China, were investigated using both live observations and protargol impregation methods. Improved diagnoses for both species are supplied based on previous and current studies. The adult form of each species has two types of tentacle, a long stalk and a ramose macronucleus. In addition, E. truncata has a short column-shaped body about 75–250 × 100–200 µm in vivo, 12–16 suctorial tentacles, 80–100 prehensile tentacles and a stalk that is 500–1200 µm long; the swarmer is ovoid, about 40 × 30 µm in vivo, with 19–24 somatic kineties and a C-shaped macronucleus. E. mammillata has a bowl-shaped body about 55–150 × 80–150 µm in vivo, ca. 10 suctorial tentacles, 30–50 prehensile tentacles and a stalk that is 350–800 µm long. The SSU rRNA genes were sequenced for both species in order to compare them with those of closely related congeners.