Étude comparée de la reproduction de Phymatolithon calcareum (Pallas) Adey & McKibbin et Lithothamnion corallioides (P. & H. Crouan) P. & H. Crouan (Corallinales, Rhodophyta), et reconsidérations sur la définition des genres

1998 ◽  
Vol 76 (8) ◽  
pp. 1433-1445 ◽  
Author(s):  
M L Mendoza ◽  
J Cabioch
Keyword(s):  
Sexual Reproduction ◽  
Type Species ◽  
Supporting Cell ◽  
Simple Type ◽  
Auxiliary Cell ◽  
Carpogonial Branch ◽  
Juvenile Stages ◽  
Fusion Cell ◽  
Main Components ◽  
First Time

The two CorallinalesPhymatolithon calcareum and Lithothamnion corallioides are the main components of European maerl communities. A large majority of the thalli are free-living branches borne on juvenile crusts that are rarely found. A detailed investigation of these juvenile stages has allowed the discovery of their reproductive features. Sexual reproduction of P. calcareum, the type-species of the genus, is described here for the first time and thus gives fundamental data for the generic definition. On the floor of the female conceptacle, a set of carpogonial branches is formed. Each fertilized carpogonium then fuses with the supporting cell of the carpogonial branch, which is also its auxiliary cell. A small fusion cell is thus formed, which produces upwards a small gonimoblast reduced to a short chain of carposporangia. In a mature conceptacle, the surface of the fertile floor thus appears entirely covered with small gonimoblasts. In the male conceptacle, mature spermatangia produced on the floor are typically dendroid; those produced on the walls are of a more simple type. The organization of the asexual conceptacle is briefly reviewed. The reproduction of L. corallioides is also newly described and compared with that previously reported for L. muelleri, the type-species of the genus.Key words: Corallinales, Phymatolithon, Lithothamnion, sexual reproduction, generic definition.

Studies of Marine algae in the lesser-known families of the Gigartinales (Rhodophyta). II. The Dicranemaceae

1977 ◽  
Vol 25 (2) ◽  
pp. 219 ◽  
Author(s):  
GT Kraft
Keyword(s):  
Marine Algae ◽  
Supporting Cell ◽  
Branch System ◽  
Auxiliary Cell ◽  
Cell Position ◽  
The Family ◽  
Red Algal ◽  
Carpogonial Branch ◽  
Advanced Stages ◽  
Fusion Cell

The red algal family Dicranemaceae (Gigartinales) has been studied with regard to its vegetative and reproductive morphology, The group is composed of two Dicranema species (D. revolutum (C. Ag.) J. Ag. and D. cincinnalis sp, nov.), Peltasta australis J. Ag., Reptataxis rhizophora (Lucas) gen. et comb. nov., and Tylotus obtusatus (Sond.) J . Ag. All except Reptataxis, from Lord Howe I., are endemic to southern Australia. The last three genera are newly added to the family, which is redefined to embrace their early gonimoblast similarities to Dicranema. The species are all multiaxial, zonately tetrasporangiate and monoecious. Dicranema, Peltasta and Reptataxis have broad, cellular cortexes and filamentous medullas, while Tylotus is pseudoparenchymatous throughout. Tetrasporangia are nemathecial in Dieranem, Reptataxis and Tylotus, but scattered in Peltasta. Spermatangia in Dicranema are formed in deeply buried catenate clusters, and are similarly derived but non-catenate in the other genera. The species are all monocarpogonial, and only Tylotus is procarpic. In none of the genera are sterile cells associated with carpogonial branches. In Tylotus the supporting cell of the carpogonial branch fuses with the presumably fertilized carpogonium and becomes the diploidized auxiliary cell. In Dicranema, Peltasta and Reptataxis, 2- or 3-celled carpogonial branches are directed to the thallus surface and presumably fertilized carpogonia fuse with an auxiliary cell not necessarily on the same cortical branch system as the supporting cell. Diploidized auxiliary cells in all four genera form small, irregular fusion cells and emit multiple, filamentous gonimoblasts. Gonimoblast growth is mostly thallus-inward in Dicranema, initially radial in Peltasta and Reptataxis, and lateral and outward in Tylotus and advanced stages of Peltasta and Reptataxis. In Dicranema, Peltasta and Reptataxis an extensive placenta of mixed and connected gonimoblast and vegetative cells forms between the fusion cell and the peripheral carpospore-producing layers. In Tylotus vegetative/gonimoblast cell connections occur mainly at the floor of the cystocarp. Carposporangia develop singly on elongate penultimate gonimoblasts in Dicranema and Tylotus, but form chains in Peltasta and Reptataxis. Cystocarps in all the genera are surrounded by thick ostiolate pericarps. The genera of the Dicranemaceae are distinct from one another on frond and holdfast habits, vegetative structure, carpogonial branch shape, auxiliary cell position, gonimoblast orientation, carposporangial size, and mature cystocarp location and cross section. None of the four genera seem obviously derived from or particularly closely related to any others outside the family, although both Peltasta and Reptataxis show some features susesting possible links to the Sarcodiaceae.

The Griffithsieae group of the Ceramiaceae (Rhodophyta) and its southern Australian representatives

1976 ◽  
Vol 24 (4) ◽  
pp. 509 ◽  
Author(s):  
RN Baldock
Keyword(s):  
Sexual Reproduction ◽  
Basal Cell ◽  
Vegetative Cell ◽  
Type Species ◽  
Small Cells ◽  
Evolutionary Trend ◽  
Multinucleate Cells ◽  
Australian Species ◽  
Branch System ◽  
Fusion Cell

The genus Griffithsia C. Agardh, with its type species G. corallinoides (L.) Batters, is characterized by subdichotomous filaments of large multinucleate cells; by a fertile axis of three small discoid cells of which the subapical cell produces 1(-2) procarp(s), whilst the lowermost cell (termed the hypogenous) produces abaxially an involucre of 2-celled branches; by a large fusion cell; and by the production of tetrasporangia and spermatangia on whorls of fascicles which often bear involucral cells, or are surrounded by an involucre from the vegetative cell beneath the fascicles, or are naked. Some southern Australian species previously placed in Monosporus Solier or Neomonospora Setchell & Gardner, but which produce tetrasporangia and reproduce sexually, are related to G. tenuis C. Agardh and G. barbata C. Agardh. They are characterized by subdichotomous filaments of multinucleate elongate cells; by a 3-celled fertile axis of which the subapical cell produces a procarp, and the hypogenous cell enlarges during procarp development and produces a whorl of 1-celled involucral branches; by a large fusion cell; and by tetrasporangia and spermatangial heads produced singly either from the basal cell of a trichoblast, or on a separate clavate pedicel. These species are referred to the genus Anotrichium Naegeli, differing from Griffithsia mainly in the spermatangial heads and tetrasporangia. The genus Monosporus Solier, represented with certainty in southern Australia only by M. australis (Harvey) J . Agardh, is retained as a form genus for those species which produce monosporangia but for which sexual reproduction is unknown. Study of Halurus equisetifolius (Lightfoot) Kuetzing, the type species of Halurus Kuetzing, from England, shows that this genus is characterized by irregularly branched axes with dichotomous whorl-branchlets; by the successive production of several fertile axes each of 3 small cells and equivalent to a condensed, dichotomous, branch system; and by a subapical procarp and large fusion cell. The involucre consists of vegetative whorl-branchlets and also a whorl of 1-celled branches from the enlarged hypogenous cell of the fertile axis. Halurus thus differs from Griffithsia mainly in cystocarpic features and the presence of whorl-branchlets. Griffithsia setacea (Ellis) C. Agardh should probably be referred to Halurus. An evolutionary trend towards reduction in the Griffithsieae is suggested: whorl-branchlets have been reduced to trichoblasts and fertile whorl-branchlets to whorls of fascicles. The number of procarps in a branch system and the female, spermatangial and tetrasporangial involucres show a reduction sequence.

Haraldiophyllum erosum comb. nov. (Delesseriaceae, Rhodophyta) from Southern and Western Australia

1996 ◽  
Vol 9 (1) ◽  
pp. 61 ◽  
Author(s):  
AJK Millar ◽  
JM Huisman
Keyword(s):  
Western Australia ◽  
Supporting Cell ◽  
Red Alga ◽  
The Other ◽  
Sterile Cell ◽  
Cell Groups ◽  
Carpogonial Branch ◽  
Fusion Cell ◽  
Cover Cell

Nitophyllum erosum Harvey (Delesseriaceae, Rhodophyta) is a branched, monostromatic red alga that is readily recognised by its distinctive fringe of branched, multicellular processes. It has been considered to be a member of the genus Myriograrnrne Kylin, since it was thought to have carposporangia borne in short chains, a feature partially diagnostic for that genus. Recent collections of female and cystocarpic material have allowed us to ascertain the structure of the procarp, a feature important in generic placement. The procarp includes two periaxial cells, of which one acts as a cover cell while the other functions as the supporting cell, ultimately bearing two sterile cell groups and a four-celled carpogonial branch. In addition, the carposporophyte includes a distinctive fusion cell that incorporates gametophytic cells from the floor of the cystocarpic cavity, and the carposporangia are single and terminal on gonimoblast filaments. This combination of characters is diagnostic of the genus Haraldiophyllurn, a genus to which we transfer this species as Haraldiophyllum erosurn (Harvey) Millar & Huisman. comb. nov.

Isolation and HPLC Determination of the Chemical Components of Gentianella acuta (Michx.) Hulten

2018 ◽  
Vol 15 (1) ◽  
pp. 21-33
Author(s):  
Ying Wei ◽  
Yongqiao Liu ◽  
Yifan Hele ◽  
Weiwei Sun ◽  
Yang Wang ◽  
...  
Keyword(s):  
Medicinal Plant ◽  
High Speed ◽  
Chemical Constituents ◽  
Folk Medicine ◽  
Gradient Elution ◽  
Chemical Components ◽  
Isolation And Characterization ◽  
Major Chemical ◽  
Main Components ◽  
First Time

Background: Gentianella acuta (Michx.) Hulten is an important type of medicinal plant found in several Chinese provinces. It has been widely used in folk medicine to treat various illnesses. However, there is not enough detailed information about the chemical constituents of this plant or methods for their content determination. Objective: The focus of this work is the isolation and characterization of the major chemical constituents of Gentianella acuta, and developing an analytical method for their determination. Methods: The components of Gentianella acuta were isolated using (1) ethanol extraction and adsorption on macroporous resin. (2) and ethyl acetate extraction and high speed countercurrent chromatography. A HPLC-DAD method was developed using a C18 column and water-acetonitrile as the mobile phase. Based on compound polarities, both isocratic and gradient elution methods were developed. Results: A total of 29 compounds were isolated from this plant, of which 17 compounds were isolated from this genus for the first time. The main components in this plant were found to be xanthones. The HPLC-DAD method was developed and validated for their determination, and found to show good sensitivity and reliability. Conclusion: The results of this work add to the limited body of work available on this important medicinal plant. The findings will be useful for further investigation and development of Gentianella acuta for its valuable medicinal properties.

Assessment of recreational use of specially protected natural territories of Tatishchevsky district of Saratov region

2019 ◽  
Vol 27 (2) ◽  
pp. 117-127
Author(s):  
Yulia M Andriyanova ◽  
Irina V Sergeeva ◽  
Yulia M Mokhonko ◽  
Natalia N Gusakova
Keyword(s):  
Natural Resources ◽  
Protected Areas ◽  
Saratov Region ◽  
Future State ◽  
Forest Phytocenoses ◽  
Long Time ◽  
Main Components ◽  
First Time ◽  
Recreational Use ◽  
Specially Protected Natural Territories

The influence of recreation being a set of measures to restore health and recreation, on the main components of forest phytocenoses in specially protected natural territories of the Tatishchevsky district of the Saratov region has been studied for the first time. These phytocenoses have been intensively used for tourism for a long time. The intensity and visits activity of protected areas has been determined; the recreational capacity of territorial objects has been studied. The degree of forest landscapes has been revealed in specially protected natural territories. The findings allow predicting the future state of the natural resources of the Saratov region and can be taken into account when assessing their optimal use.

Taxonomic revision of Cylindera Westwood, 1831 subgenus Parmecus Motschulsky, 1864 stat. rest., stat. nov. (Coleoptera: Carabidae: Cicindelinae) with the description of one new species from Yunnan Province, China

Zootaxa ◽  
2019 ◽  
Vol 4706 (1) ◽  
pp. 48-70
Author(s):  
ANDREY V. MATALIN
Keyword(s):  
New Species ◽  
Type Species ◽  
Yunnan Province ◽  
Taxonomic Revision ◽  
Jammu And Kashmir ◽  
Tiger Beetle ◽  
Indian State ◽  
Chinese Province ◽  
First Time ◽  
One New Species

Within the Asiatic tiger beetle fauna, Parmecus Motschulsky, 1864 stat. rest., stat. nov., is reestablished as a subgenus of Cylindera Westwood, 1831 with Cylindera (Parmecus) dromicoides (Chaudoir, 1852), as its type species, and the lectotype and paralectotypes of Cicindela dromicoides Chaudoir, 1852 are designated as well. Two other species are included, Cylindera (Parmecus) armandi (Fairmaire, 1886), from the Himalayan Region, and Cylindera (Parmecus) mosuoa, sp. nov., from Yunnan, China. Cylindera (Parmecus) as a subgenus is characterized, a key to identify its species is provided, and its species composition is discussed. Cylindera (Parmecus) dromicoides (Chaudoir, 1852) is newly recorded from Pakistan and the Indian state of Jammu and Kashmir, while Cylindera (Parmecus) armandi (Fairmaire, 1886) is recorded for the first time from the Chinese province of Sichuan. The records of C. armandi from Bhutan, as well as C. dromicoides from Yunnan Province (China) are rejected due to erroneous identifications. 

Synthesis, Crystal Structure, Luminescence and Electronic Band Structure of K2BiZr(PO4)3 Phosphate Compound

2015 ◽  
Vol 230 ◽  
pp. 55-61 ◽  
Author(s):  
Vitalii Chornii ◽  
Yuriy Hizhnyi ◽  
Sergiy G. Nedilko ◽  
Kateryna Terebilenko ◽  
I. Zatovsky ◽  
...  
Keyword(s):  
Electronic Band Structure ◽  
Spontaneous Crystallization ◽  
Electronic Band ◽  
Coordination Numbers ◽  
Crystallization Method ◽  
Oxygen Coordination ◽  
Spectroscopy Studies ◽  
Main Components ◽  
Flapw Method ◽  
First Time

The single crystals of langbeinite-related K2BiZr(PO4)3 have been obtained for the first time by spontaneous crystallization method from K-Zr-P-O-F molten system. The compound crystallizes in a space group P213 with cell parameter a = 10.30360 Å. The framework is built up from isolated Bi/ZrO6 octahedra connected together by PO4 units. For the two K+ cations two types of oxygen coordination numbers 9 and 12 are observed. The photoluminescence (PL) spectroscopy studies of K2BiZr(PO4)3 are carried out under the VUV synchrotron excitations. The electronic structure of K2BiZr(PO4)3 crystal is calculated by the FLAPW method. The PL spectra reveal two main components in the UV and visible spectral regions (peaking near 3.6 and 2.7 eV respectively). It is assumed that the <st1:address><st1:street>UV PL</st1:street></st1:address> component of K2BiZr(PO4)3 originates from transitions in ZrO6 polyhedra, while the visible one is related to Bi3+ ions in oxygen coordination.

Resurrection of the genus Similisinocarum (Apiaceae) based on evidence from morphology and ITS sequences

Phytotaxa ◽  
2021 ◽  
Vol 497 (2) ◽  
pp. 127-137
Author(s):  
XIAN-LIN GUO ◽  
MEGAN PRICE ◽  
WEI GOU ◽  
SONG-DONG ZHOU ◽  
XIN-FEN GAO ◽  
...  
Keyword(s):  
Type Species ◽  
Genetic Distances ◽  
Its Sequences ◽  
Evidence Based ◽  
Molecular Phylogenetic ◽  
First Time ◽  
Entire Margin

The genus Similisinocarum Cauwet & Farille (Apiaceae, Apioideae), was first described by Cauwet & Farille in 1984, but it has been considered as a synonym of Sinocarum H.Wolff ex R.H. Shan & F.T. Pu. In this study, Simlisinocarum normanianum, the type species of Similisinocarum was found in China for the first time, and the molecular phylogenetic evidence based on ITS sequences reveals that Similisinocarum normanianum occupies an individual clade, which is sister to the clade comprising seven species of Acronema, Sinocarum, and Oreocomopsis in Acronema clade, the values of genetic distances (ITS) between Similisinocarum and Acronema, Similisinocarum and Oreocomopsis, Similisinocarum and Pternopetalum, Similisinocarum and Sinocarum are close (≥0.0916), while deviated from the values within Acronema, Sinocarum and Pternopetalum (≤0.0580). Morphologically, we found Similisinocarum normanianum develops reflex bracteoles with white membranous margin, petals with an entire margin and incurved apex, and mericarps with many vittae in the furrow (≥ 3) and commissure (6), which are distinguishable from other species of the Acronema clade. Consequently, results manifested in molecular and morphological analyses indicate that Similisinocarum should be treated as an independent genus distinct from Sinocarum.

Comparative analysis of the effect of epibrassinolide and 6-benzylaminopurine on the key components of the glutathione complex in the roots of wheat seedling under salinity.

Biomics ◽  
2021 ◽  
Vol 13 (1) ◽  
pp. 20-26
Author(s):  
D.R. Maslennikova ◽  
F.M. Shakirova
Keyword(s):  
Comparative Analysis ◽  
Wheat Seedling ◽  
Glutathione System ◽  
Glutathione S Transferase ◽  
Wheat Seedlings ◽  
Comparable Level ◽  
Endogenous Cytokinins ◽  
Main Components ◽  
First Time

The study carried out a comparative analysis of the effect of 24 epibrassinolide (EB) and 6-benzylaminopurine (BAP) on the growth and state of the main components of the glutathione system in the roots of wheat seedlings under the action of 2% NaCl, which for the first time revealed the ability of these phytohormones to similarly stabilize stress-induced decrease GSH / GSSG ratio, positively regulate the activity of glutathione reductase and glutathione-S-transferase. A comparable level of protective effect of BAP and EB on root length was revealed. The data obtained indicate that endogenous cytokinins may play the role of hormonal intermediates in the implementation of the protective.

A cladistic revision of Tortopus Needham & Murphy with description of the new genus Tortopsis (Ephemeroptera: Polymitarcyidae)

Zootaxa ◽  
2010 ◽  
Vol 2481 (1) ◽  
Author(s):  
CARLOS MOLINERI
Keyword(s):  
Phylogenetic Analysis ◽  
Fore Wing ◽  
Type Species ◽  
New Genus ◽  
Lateral View ◽  
Median Line ◽  
Male And Female ◽  
Line Drawings ◽  
Neotropical Species ◽  
First Time

The 12 species previously placed in Tortopus together with 3 species newly described here, are revised and included in a phylogenetic analysis. Based on synapomorphic characters on the nymphs and adults of both sexes, Tortopus is restricted to T. igaranus Needham & Murphy, T. circumfluus Ulmer, T. harrisi Traver, T. zottai (Navás), T. bellus Lugo-Ortiz & McCafferty, and T. arenales sp. nov., and the genus is defined by: female parastyli receptors with long furrows anterior to sockets; penes entirely flattened; male ninth abdominal sternum almost separated in two portions by a median notch; mesosternum with furcasternal protuberances contiguous only on basal corner; and nymphs with two subapical tubercles on mandibular tusks. Tortopsis is newly described for T. bruchianus (Navás), T. limoncocha sp. nov., T. obscuripennis (Domínguez), T. parishi (Banks), T. primus (McDunnough), T. puella (Pictet), T. sarae (Domínguez), T. spatula sp. nov., and T. unguiculatus (Ulmer). Tortopsis is characterized by: R sector of female fore wing without additional veins between R 2 and IR; female parastyli receptors C or V-shaped, with sockets opening towards median line; male gonopore associated with a claw-like structure; penes separated from the base; parastyli more than 5 times length of pedestals; parastyli curved in lateral view; nymphs with a single subapical tubercle on mandibular tusks. The study of available type material permitted inclusion of comparative diagnoses, with figures and redescriptions as needed. The male imago of the type species of Tortopus (T. igaranus Needham & Murphy) is described for the first time, as are the female adults of Tortopus bellus Lugo-Ortiz & McCafferty and T. harrisi Traver. Three new Neotropical species based on male and female adults are described: Tortopus arenales and Tortopsis limoncocha from Ecuador, and Tortopsis spatula from Colombia. Keys to separate the adults and nymphs of the genera of Polymitarcyidae, and for male and female adults of all the species of Tortopus and Tortopsis are presented, as well as line drawings, pictures and SEM photographs of important structures.

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