Species Of Mastogloia Research Articles

Stigmagloia lobbanii gen. et sp. nov. (Bacillariophyceae, Mastogloiales), a new stigma-bearing diatom genus separated from Mastogloia

The genus Mastogloia comprises mainly marine diatoms with a modified and specialized valvocopula called partecta. We isolated a new species, morphologically similar to M. cyclops, from the coastal waters of Viet Nam. A detailed study using light and scanning electron microscopy as well as molecular phylogenetic analysis based on SSU rDNA and rbcL sequences led us to describe a new genus and species, Stigmagloia lobbanii gen. et sp. nov. The main difference between Stigmagloia and Mastogloia is the presence of a stigma. The differences between S. lobbanii and M. danseyi, the type species of Mastogloia, are discussed. Mastogloia cyclops is transferred to Stigmagloia and a new combination, S. cyclops comb. nov., is proposed.

New insights into the association between epizoic diatoms and the sea turtle Chelonia mydas: new Mastogloia taxon (Bacillariophyceae) from Iran

ABSTRACT Two epizoic species of Mastogloia, one of them a new taxon, have been found for the first time growing on the carapace of sea turtle Chelonia mydas from the Strait of Hormuz (Iran). Before this work, taxa belonging to the genus Mastogloia had never been identified as epibionts of C. mydas. The cleaned material of diatoms, collected from turtle carapaces was studied by light (LM) and scanning electron microscopy (SEM). Mastogloia hormuzensis sp. nov. is elliptical to linear-elliptical in valve view with rounded to slightly rostrate apices. Partecta are of different size and shape, with the larger one at the centre, and there is a very short partectal flange. The new epizoic diatom is unique in its morphology, and can be compared with Mastogloia exigua and M. pusilla, which show a similar combination of characters (e.g. the shape of areolae, type of partectal ring). Mastogloia hormuzensis sp. nov. fits into Hustedt’s species group Inaequales, to which it adds the feature of having a very short partecta flange. A second species, Mastogloia paradoxa, was also found living as epizoic for the first time.

Additions to the Mastogloia (Bacillariophyceae: Mastogloiales) of the Revillagigedo Archipelago, Mexico

Certain diatom species, mainly those that are conspicuous within an assemblage, may constitute useful references while addressing various ecological and biogeographical issues. This may well be the case with Mastogloia species which are frequently the most diverse diatom taxa in benthic marine assemblages from warm seas. Twenty three new records of Mastogloia taxa collected from several thalli of red and brown macroalgae are here added to the epiphytic diatom floristics of the Revillagigedo Archipelago, summing a total of 51 Mastogloia taxa. Most conspicuous forms were frequent, and several taxa seemed to dominate the assemblages, e.g., Mastogloia binotata, M. cocconeiformis, M. cuneata, M. fimbriata, M. inaequalis, M. ovum-paschale, and M. punctatissima, as well as others recorded earlier. Of the new records, M. asperuloides, M. graciloides, M. peragalloi, and M. mauritiana also appeared frequently. The list includes 8 new records for Mexican waters, although no new taxa for this genus were found. However, because of the few macroalgae thalli inspected, it is expected that further inspection of surfaces of other species of macroalgae, and other substrates, will increase the species richness of Mastogloia recorded for the archipelago.

<p><strong><em>Mastogloia jahniae sp. nov.</em>, a new diatom (Bacillariophyceae) from the Baltic Sea coast of Sweden</strong></p>

Described is here Mastogloia jahniae sp. nov. a species new to science from Skatan on the Baltic Sea, east coast of Sweden. Description of this new species is based on light and scanning electron microscopy. The new species is classified in the Mastogloia section Ellipticae and is characterized by having radiating short and long striae around the central area, sinuous raphe branches and partecta displaced toward the middle of the valve by a siliceous flange. M. jahniae sp. nov. in terms of size is rather small whereas in terms of ecology appears an epipelic brackish water species. The new species was rather rare in all samples collected from Skatan and has not been found in the other adjacent regions sampled. A comparison with similar established Mastogloia species is provided.

High species richness of epiphytic Mastogloia (Mastogloiales: Bacillariophyceae) on Thalassia testudinum along the coast of Campeche, southern Gulf of Mexico

Diatoms of the genus Mastogloia are naviculoid forms that are generally easy to discriminate due to the presence of marginal chambers known as partecta. They exhibit a wide marine distribution, and are basically benthic forms usually conspicuous in epiphytic and epipelic diatom assemblages. Our objective was to identify species of Mastogloia epiphytic on Thalassia testudinum blades from the southern Gulf of Mexico region. Blades of T. testudinum were collected off the coast of Campeche State, Mexico; the epiphytic diatoms were scrapped off, cleaned and mounted on permanent slides for identification under light microscopy. A total of 76 Mastogloia taxa were recorded. This is the highest number of Mastogloia taxa recorded for Mexican coasts. Seven taxa had not been observed for the region: Mastogloia angusta, M. belaensis, M. depressa, M. ovalis, M. pseudolacrimata, M. regula, and M. urveae . Likewise, 20 Mastogloia species are new records for the Gulf of Mexico, while 15 are new records for Mexican coasts overall. This study confirms that Mastogloia species are mostly distributed in tropical and subtropical habitats, and shows that much floristics and formal taxonomy are required on benthic diatoms from different types of substrata for Mexican littorals.

Morphology of two Mastogloia species (Bacillariophyta) from Lac de Guiers (Senegal) and comparison with the type material of M. braunii

Two Mastogloia Thwaites ex W.Sm. taxa were found during a survey of the diatom flora of Lac de Guiers, Senegal. Based on all currently available literature, one taxon could be identified as M. belaensis M.Voigt, a species formerly described from Pakistan. The second species showed some resemblance to M. braunii Grunow. Analysis of the type of M. braunii revealed, however, important morphologic differences, leading to the description of a new species from the Senegal population: M. senegalensis Van de Vijver, Fofana, Sow & Ector sp. nov. The present paper describes this new species and discusses and illustrates the morphology of M. belaensis and the type of M. braunii. All taxa are discussed with morphologically similar taxa.

Mastogloia abnormis sp. nov. and Mastogloia descrepata sp. nov. (Bacillariophyceae, Mastogloia section Sulcatae) from Sawa Lake, Southern Iraq

Two new species of Mastogloia, M. abnormis and M. descrepata, are described from the saline Sawa Lake, in South Iraq. These species belong to the Mastogloia section Sulcatae, which is characterized by the presence of a central furrow on the external valve face. Descriptions of these species are based on light microscope (LM) and scanning electron microscope (SEM) features that distinguish them from other taxa. Mastogloia abnormis exhibits few morphological features that are not shared by any described species in the genus, while M. descrepata is similar to, but distinct from, M. vestigiostriata, M. belaensis, and M. braunii. Both taxa were found as epiphytes on the submerged Lamprothamnium sp. that is dominant on the bottom of Sawa Lake. Environmental conditions where the species were common included high salinity and elevated concentrations of calcium sulphate (gypsum). The ecology of these new species is discussed.

Phylogenetic Relationships and Biogeography of the Diatom Genus Mastogloia (Bacillariophyceae): Revision of the Section Ellipticae Including the Description of New Taxa

Benthic diatoms represent an important component of aquatic ecosystems, both for their contribution to primary production and their role in the marine food web. Mastogloia is a large, mostly marine diatom genus occurring in microphytobenthic communities of temperate to tropical coastal regions. In this study, the phylogenetic relationships, based on cladistic methodologies using morphological features, among all taxa belonging to the genus Mastogloia section Ellipticae (i.e., 33 taxa) were investigated using the parsimony method. The character states that describe variations of central area, raphe, areola vela and partectal position have a tendency to be very homologous and useful in recovering phylogenies. The typical character states of this section, such as rounded apices represents an ancestral homology. The phylogenetic hypothesis supports the probable monophyletic origin of the section Ellipticae (synapomorphy). Moreover, we completed the taxonomical review of the section Ellipticae, with the description of seven species, M. cocconeiformis, M. cribrosa, M. fimbriata, M. ovata, M. pseudolatecostata, and of two species new to science, M. rosalbae and M. aegyptiaca. Finally, this study provides historical and new information on the geographical distribution of Mastogloia species.

Two new species of Mastogloia Thwaites ex W. Smith (Bacillariophyceae) from Sawa Lake, southern Iraq

Two new species of the genus Mastogloia are described. Mastogloia sawensis sp. nov. and M. vestigiostriata sp. nov. were encountered as epiphytes on Chara sp. which covers the sediment of Sawa Lake, an isolated saline water body in southern Iraq. Mastogloia sawensis belongs to the section Lanceolatae and is closely similar to M. lanceolata but differs in raphe curvature, areolae shape and arrangement, and the presence of rounded pores at the junction of the partecta. Mastogloia vestigiostriata resembles under light microscopy to M. lyra and M. braunii but shows differences in several features including valve mantle structures, H-shaped lateral hyaline area, siliceous flanges and partectal formation. This study gives morphological details on the ultrastructure of the new species and provides a detailed comparison with all related taxa.

Two new Mastogloia species (Bacillariophyceae), M. parlibellioides and M. lyra, from coral reefs in Guam, Western Pacific1

Abstract This paper describes the morphology of two new species of Mastogloia identified during a survey of the marine benthic diatom flora of Guam. Mastogloia parlibellioides sp. nov., classified in the section Decussatae, is distinctive in the combination of its valve shape and stria pattern reminiscent of Parlibellus, as well as the presence of rudimentary division walls extending from the free margin to the middle of each partectum. Mastogloia lyra sp. nov., classified in the section Sulcatae, subgroup 2, has internal lyre-shaped lateral sterna and partecta that are displaced toward the midline of the valve by a siliceous flange, which shows oblique partectal ducts. The descriptions of these two new species increase the knowledge base of biodiversity in a Pacific Ocean Mastogloia hotspot.

Comparison of two new species of astogloia Bacillariophyceae) with other small members of section Ellipticae

In this study, seven Mastogloia species belonging of the section Ellipticae are morphologically described through scanning electron microscopy, including two new taxa M. matthaei and M. stellae. They were collected as epiphytes on seagrasses from several tropical (Indonesia), subtropical (Egypt, Greece, Republic of Malta, Turkey) and temperate (Slovenia, Italy) regions of the world. All these species show typical characters of the Hustedt’s section Ellipticae: elliptical valve outline, a flat valve surface and rounded apices. Moreover, this study provides novel information on the frustule ultrastructure and gives update of their current geographical distribution. Some nomenclatural inconsistencies have been resolved with the typification of M. ovulum and the related species, M. emarginata, from the original Miang Besar material in the Hustedt collection.

MORPHOLOGICAL STUDIES OF SOME MARINE MASTOGLOIA (BACILLARIOPHYCEAE) BELONGING TO SECTION SULCATAE, INCLUDING THE DESCRIPTION OF NEW SPECIES.

Epiphytic diatoms on seagrass and seaweed were collected from tropical (e.g., Siladen Island, Celebes Sea, Indonesia and Phú Bài, China Sea, Vietnam), subtropical (e.g., Sharm el-Sheikh, Red Sea, Egypt), and temperate regions (e.g., Patmos Island, Greece) in 2000, 2005, and 2006. Eight species of Mastogloia, belonging to the section Sulcatae, are described mainly through scanning electron microscopy, including two new species to science, M. oculoides and M. sergiana. These species show a differently shaped median depression on the external valve face between the raphe-sternum and the valve margin. Moreover, they lack a developed conopeum or pseudoconopeum, which covers the median depression in other species of the section Sulcatae. This study gives new insights on the ultrastructure of the Mastogloia's valves and provides an update of their current geographical distribution.

An illustrated survey on the morphological characters in three species of the diatom genus Mastogloia (Bacillariophyceae)

The valve morphology of Mastogloia braunii Grunow, Mastogloia pumila Cleve, and Mastogloia vasta Hustedt were investigated using field material. Specimens for study were collected from Homa Lagoon, İzmir Bay, Turkey (4-29 °C; salinity 35%o-54%o) as epipelic and epiphytic (Ulva lactuca L.). The valve morphological characteristics of the 3 species were measured by calibrated ocular micrometer using 20 specimens from each species per station. The valve of M. braunii was 35.15-80.20 µm in length and 12.35-19.85 µm in width, the valve of M. pumila was 13.70-31.85 µm in length and 5.75-9.00 µm in width, and the valve of M. vasta was 31.20-43.35 µm in length and 11.90-18.10 µm in width. The results of Pearson's correlation analysis revealed significant correlations among morphological features and environmental factors. All of the species display a positive correlation between valve length and valve width, and the number of transapical striae in 10 µm are invariable with changes in environmental factors. Seasonal differences in the morphological features of Mastogloia species were determined by one-way ANOVA analyses. Valve length, valve width, and total number of partecta were the common characteristics showing seasonal variation.

New insights to the ultrastructure of some marine Mastogloia species section Sulcatae (Bacillariophyceae), including M. neoborneensis sp. nov.

Pennesi C., Poulin M., De Stefano M., Romagnoli T. and Totti C. 2011. New insights to the ultrastructure of some marine Mastogloia species section Sulcatae (Bacillariophyceae), including M. neoborneensis sp. nov. Phycologia 50: 548–562. DOI: 10.2216/10-39.1This paper describes the morphology of six Mastogloia species of the section Sulcatae, including one new species, M. neoborneensis. Specimens were collected from seagrass and macroalgae in tropical (Siladen Island, Celebes Sea, Indonesia), subtropical (Sharm el-Sheikh, Red Sea, Egypt) and temperate (Patmos Island, Aegean Sea, Greece) regions. Scanning electron microscopy observations showed that all six species, M. baldjikiana, M. borneensis, M. hustedtii, M. mediterranea, M. neoborneensis and M. umbra, have different-shaped median depressions on the external surface of the valve face between the raphe-sternum and the margin, and variably developed siliceous outgrowths (conopeum and pseudoconopeum) covering the depressions to various degrees. This study provides new information on the frustule ultrastructure and geographical distribution of these Mastogloia species.

MORPHOLOGICAL AND TAXONOMICAL STUDIES OF CERTAIN DIATOM SPECIES BELONGING TO FAMILY NAVICULACEAE

The objective of this work is to investigate some small-celled diatom species and to reconfirm identification of three species of large-celled naviculoid diatoms. Specimens of this investigation were collected from fresh and marine water habitats in Egypt. These specimens were examined using LM and SEM. Seven species of the genus Navicula Bory are described in this study, six of them are belonging to the sub-genus Navicula, while other one (7 th) is belonging to the sub genus Minuscula. Full description using LM and SEM, distribution in Egypt, ecological status and comparison between small celled naviculoid diatoms are given. These species are Navicula cryptocephela, N. gregaria, N. viridula, N. heufileri, N. lanceolata, N. pseudoreinharadti and N. luzonensis. This study added a new record to the diatom flora of Egypt and confirm the identification of Pinnularia alpina and two species of Mastogloia.

A DESCRIPTION OF TWO NEW SPECIES OF THE DIATOM GENUSMASTOGLOIAWITH FURTHER OBSERVATIONS ONM. AMOYENSISANDM. GIESKESII

The SEM study extends the morphological limits of two previously published species of Mastogloia, M. amoyensis Voigt and M. gieskesii Cholnoky, and describes two new species, M. cannii and M. discontinua.

Diatom Succession in a Core from Pickerel Lake, Northeastern South Dakota

Percentage analyses of the diatoms from a core of sediment show the changes in the community since the formation of Pickerel Lake. The lake basin is in calcareous drift from the Wisconsin glaciation and is located on the Coteau des Prairies upland. This work supplements earlier studies of the pollen, plant macrofossils, and mollusks made by Watts and Bright (1968), in which they presented evidence for four vegetational stages: (1) spruce forest, (2) deciduous woodland, (3) bluestem prairie, and (4) continued open prairie with the return of some woodland. The diatom core was correlated with the nearby pollen core by pollen analysis. The diatom succession begins in diatom zone I, with an assemblage dominated by Fragilaria and Mastogloia species and containing many taxa of alkaline waters. It also includes several taxa that generally prefer acid environments and only occur in the lower part of this core. This diatom assemblage is correlated primarily with the presence of spruce forest and its associated soils; the change in the diatoms occurs when the deciduous woodland that follows is partly replaced by prairie openings. It is suggested that the changes in the type of material (mainly soil) washed into the lake produced a more alkaline environment, which excluded some of the acidophilous taxa. Diatom zone II is largely transitional to zone III, which is dominated by Melosira species and includes many indicators of a more eutrophic (nutrient-rich) environment, for example Fragilaria crotonensis. More brackish-water taxa also indicate an increase in the mineral content of the water. All of these features are consistent with evidence from the pollen stratigraphy, which indicates that this is the time of maximum prairie development in this area, along with maximum soil erosion and lake-water evaporation. Diatom zone IV is largely transitional, corresponding to the time when woodland was once again developing around the margins of the lake basin. Diatom zone V features increasing percentages of forms characteristic of surf zones in lakes, indicating perhaps a shallowing of the site as a result of sedimentation. There is some indication of recent enrichment, concurrent with an increase in Ambrosia pollen (ragweed), which is possibly due to disturbance by man. The use of a constant volume of material in the diatom preparation makes it possible to draw a diagram of diatom abundance for each level. The diatoms are scarce in samples from the lower part of the core, and four radiocarbon dates bear out a suggestion that more inorganic material was deposited at the core site during the early history of the lake than subsequently. A total of 207 taxa is reported, and ecological notes on all are included in an appendix. A diatom diagram shows curves for 71 of the taxa.

Diatoms attached to floating Sargassum in the western Sargasso Sea

Abstract Thirteen species of diatoms, including two new species, were observed as epiphytes on Sargassum collected at seven locations in the western Sargasso Sea. The most widespread species was Mastogloia binotata (Grun.) C1., being found at all seven locations. Eight species of Mastogloia were observed along with one each of Cyclotella, Cocconeis, Nitzschia, Synedra, and Navicula. In comparison with epiphytic diatoms from inshore and freshwater areas, the number of species of diatoms on floating Sargassum is relatively low.

SOME NEW AND INTERESTING MASTOGLOIA FROM THE MEDITERRANEAN AREA AND THE FAR EAST

SYNOPSISAfter some general remarks concerning the interpretation of certain structural markings of Mastogloia, which have hitherto often been neglected, but which must now be considered as being of value in separating otherwise similar species, some new Mastogloia are described, in the first part from collections made in the Mediterranean area. The second part comprises descriptions of a number of Mastogloia species from the Far East, omitted from previous papers owing, mostly, to the fact that specimens suitable for photomicrographic reproduction had not been found when these were published.In order to facilitate reference, the species are again arranged in alphabetical order.