Precise flagellar configuration of the Rhizophlyctis harderi zoospore

1992 ◽  
Vol 70 (4) ◽  
pp. 762-771 ◽  
Author(s):  
Sonali Roychoudhury ◽  
Martha J. Powell
Keyword(s):  
Key Words ◽  
New Genus ◽  
Flagellar Apparatus ◽  
The Other ◽  
Taxonomic Position ◽  
Serial Sections ◽  
Microtubular Roots

Rhizophlyctis harder is a questionable member of the genus Rhizophlyctis, and more stable and reliable characters are needed to establish the taxonomic position of this chytrid. As a source of such characters the flagellar apparatus of zoospores of R. harderi was reconstructed from serial sections, and the precise configuration was determined. The flagellar apparatus included two major microtubular roots, each with separate points of origin near the kinetosome. Root A extended laterally from one side of the kinetosome toward and around one rumposome and then continued anteriorly. The other, root B, originated between the kinetosome and secondary centriole near fibrillar connecting material and projected anteriorly into the cytoplasm. Each of these two major roots branched into two rootlets. This system of microtubular roots is more complex than that found in the flagellar apparatus of other Chytridiomycetes presently described. The structure of the flagellar apparatus and accompanying roots clearly separates this species from others in the genus Rhizophlyctis and indicates that it can be used to establish a new genus in the Chytridiales. Key words: Rhizophlyctis harderi, Chytridiales, zoospores, flagellar apparatus, ultrastructure.

Convergence with naticids: phenotypic phylogenetic study on some Antarctic littorinoideans, with description of the zerotulid new genusPseudonatica, and its presence in Brazil (Mollusca, Caenogastropoda)

2017 ◽  
Vol 98 (6) ◽  
pp. 1365-1381
Author(s):  
Luiz Ricardo L. Simone
Keyword(s):  
Phylogenetic Analysis ◽  
Type Species ◽  
New Genus ◽  
The Other ◽  
Taxonomic Position ◽  
Phylogenetic Study ◽  
Brazilian Coast ◽  
Antarctic Species ◽  
Oesophageal Gland ◽  
Phenotypic Characters

Some Antarctic littorinoideans have a remarkable convergence with Naticoidea in shell and operculum features. Two naticid-like species of that group are studied in their phenotypic features in order to improve their taxonomy and to discuss the meaning of that convergence, as the former are herbivore-detritivore and the latter active predatory organisms. One of the studied species is the littorinidLaevilacunaria antarctica(Martens, 1885). The other belongs to a new genus –Pseudonatica, with the type species also newly described:P. antarctica, the genus is tentatively placed in Zerotulidae. Another Pseudonatica is also described,P. ampullarica, based only on shells collected by Marion-Dufresne French expedition off Brazilian coast, this finding expands the occurrence of zerotulids northwards. Besides the similarities of shell and operculum, other structures of these Antarctic species also show singular similarities with naticoideans, such as the wide foot, the complexity of opercular attachment in pedal opercular pad, the wide oesophageal gland, and the coiled arrangement of the pallial oviduct. The phenotypic characters were coded and inserted in a previous large phylogenetic analysis on Caenogastropoda (Simone, 2011), furnishing a wide basis for discussion on the characters, taxonomic position, evolution and adaptations of these organisms.

Primagistemus gen. nov. (Acari: Prostigmata: Stigmaeidae)

Zootaxa ◽  
2002 ◽  
Vol 29 (1) ◽  
pp. 1
Author(s):  
QING-HAI FAN ◽  
ZHI-QIANG ZHANG
Keyword(s):  
New Species ◽  
New Zealand ◽  
New Genus ◽  
The Other ◽  
Taxonomic Position ◽  
Fujian Province ◽  
Adult Females ◽  
A New Species

Primagistemus gen. nov. (Acari: Stigmaeidae) is described and its taxonomic position discussed. Adult females of this new genus are distinguished from those of Agistemus by having four pairs of setae on the propodosomal shield, by lacking postocular bodies, by having three pairs of aggenital setae and by having two setae on genu II. They are also distinguished from those of Stigmaeus by the terminal eupathidia on the palptarsus mostly fused and subterminally separated into three minute prongs, by both subcapitular setae posterolaterad of the pharynx, by having only one seta on coxa II, and by lacking endopodal shields around coxae III-IV. A new species, Primagistemus wuyiensis, from leaves of Araucaria sp. in Fujian Province of China, is described and illustrated. This new species is distinguished from the other species of the genus from New Zealand, Primagistemus loadmani (Wood) comb. nov. (transferred from Stigmaeus), by the distally truncated dorsal body setae and by setal lengths.

Further observations on the type subgenus of Pyramimonas (Prasinophyceae), with particular reference to a new species, P. chlorina, and the flagellar apparatus of P. propulsa

1997 ◽  
Vol 75 (12) ◽  
pp. 2196-2215 ◽  
Author(s):  
Stuart D. Sym ◽  
Richard N. Pienaar
Keyword(s):  
New Species ◽  
Key Words ◽  
South African ◽  
Flagellar Apparatus ◽  
Primitive Form ◽  
Unique Structure ◽  
Inshore Waters ◽  
Microtubular Roots ◽  
A New Species

A new quadriflagellate species of Pyramimonas isolated from South African inshore waters is described. It has ultrastructural features most consistent with the subgenus Pyramimonas McFadden. The flagellar apparatus of this organism is basically of the 3-1 type, but a unique structure, which may be considered a homologue of the R2-associated fiber found in Pterosperma cristatum, is associated with the 1s root. It thus could be construed as an alternate primitive form of the genus to Pyramimonas mucifera Sym & Pienaar. The flagellar apparatus of Pyramimonas propulsa Moestrup & Hill has surprising differences to that of Pyramimonas octopus Moestrup. Hori, & Kristiansen, particularly with regard to the microtubular roots and the distal fibrillar bands. Features of these two species, together with those extracted from the literature, show a considerable overlap between the subgenera Pyramimonas and Punctatae but, ironically, it is considered inappropriate at this time to combine the two subgenera because of anomalies exhibited by the new species. Key words: flagellar apparatus, Pyramimonas subgen. et gen., P. chlorina sp.nov., P. longicauda, ultrastructure.

scholarly journals A new fossil soldier beetle (Coleoptera, Cantharidae, Silinae) from Eocene Baltic amber

Zootaxa ◽  
2018 ◽  
Vol 4370 (2) ◽  
pp. 189 ◽  
Author(s):  
FABRIZIO FANTI ◽  
MICHAEL J. PANKOWSKI
Keyword(s):  
New Genus ◽  
Morphological Characteristics ◽  
The Other ◽  
Taxonomic Position ◽  
Baltic Amber ◽  
Lateral Margin ◽  
New Taxon ◽  
New Genus And Species

A new genus and species of fossil soldier beetle Markus karenae gen. et sp. nov. is described and illustrated from Eocene Baltic amber. Its morphological characteristics place it in the taxonomic position of the subfamily Silinae. It is characterized by a particular lateral pronotal shape with two difform processes, pronotum slightly longer than wide, with a blunt and evident angle near the basal angles, anterior and posterior margins flat and with shallow punctation, and lateral margin strongly granulose and in relief. Furthermore, each of its legs has a claw with one acute tooth at the base, except for the posterior legs where the tooth appears to be blunt. The new taxon is morphologically compared with the other fossil representatives of Silinae from Baltic amber, and with extant Palearctic genera. 

Ultrastructure and reconstruction of the flagellar apparatus in Chrysochromulina apheles sp. nov. (Prymnesiophyceae = Haptophyceae)

1986 ◽  
Vol 64 (3) ◽  
pp. 593-610 ◽  
Author(s):  
Øjvind Moestrup ◽  
Helge A. Thomsen
Keyword(s):  
Electron Microscopy ◽  
Fine Structure ◽  
New Zealand ◽  
Coastal Waters ◽  
Type Species ◽  
Light And Electron Microscopy ◽  
Flagellar Apparatus ◽  
Marine Species ◽  
Serial Sections ◽  
Microtubular Roots

A new marine species of Chrysochromulina, C. apheles, is described from light and electron microscopy of a culture established from Danish coastal waters. The cells are among the smallest known in any species of Chrysochromulina, measuring ca. 4 μm in diameter. The general fine structure is illustrated and the structure of the haptonema and the flagellar apparatus is described in detail, based on serial sections. The flagellar root system, not previously examined in detail in any member of Chrysochromulina, is shown to consist of four microtubular roots, while cross-banded roots are lacking. Four cross-banded fibres were seen to interconnect the flagellar bases and the haptonema base. The haptonema belongs to the rather unusual six-stranded type. Two very similar looking types of small organic scales are present on the cell body. Unpublished data on the flagellar roots of the type species of Chrysochromulina, C. parva, are included. Chrysochromulina apheles is apparently cosmopolitan. It has presently been found in material from Denmark, Finland, England, Thailand, Australia, and New Zealand.

scholarly journals A new family for a deep-sea caridean shrimp from North Atlantic hydrothermal vents

1997 ◽  
Vol 77 (2) ◽  
pp. 425-438 ◽  
Author(s):  
A.L. Vereshchaka
Keyword(s):  
North Atlantic ◽  
Deep Sea ◽  
Hydrothermal Vents ◽  
New Genus ◽  
The Other ◽  
Taxonomic Position ◽  
Caridean Shrimp ◽  
New Family ◽  
The Family ◽  
Mid Atlantic Ridge

Mirocaris keldyshi gen. nov., sp. nov. is described from the Mid-Atlantic Ridge, TAG Location (26°09′N 44°50′W). The family Mirocarididae is proposed to include the new genus. The taxonomic position and distinguishing characters (presence of hook-bearing thoracic epipods and rudimentary appendix interna on pleopods 2–4) of the new family as compared to the other families of the superfamily Bresilioidea (Bresiliidae, Disciadidae, and Alvinocarididae) are discussed, and revised diagnoses for these families are provided.

Reexamination of six taxa described in Leptosphaeria from species in the Ranunculaceae

1995 ◽  
Vol 73 (4) ◽  
pp. 573-582 ◽  
Author(s):  
Young-mee Ahn ◽  
C. A. Shearer
Keyword(s):  
Key Words ◽  
Plant Species ◽  
New Genus ◽  
Fungal Species ◽  
Taxonomic Position ◽  
Original Position ◽  
Authentic Materials

Six fungal species previously placed in Leptosphaeria and originally described on plant species in the Ranunculaceae were reevaluated for their proper taxonomic position and redescribed and illustrated from the type and authentic materials. The original position of Leptosphaeria nigromaculata as Ophiobolus nigromaculata is confirmed. Metasphaeria rupicola is transferred to Massarina, and a lectotype is designated. Leptosphaeria scotophila and Leptosphaeria thorae are transferred to Phaeosphaeria, and a lectotype is designated for L. scotophila. The previous transfer of Leptosphaeria anthostomoides to Montagnula anthostomoides is confirmed. The new genus Barrella is established and typified by Leptosphaeria thalictri, and a neotype is designated. Key words: systematics, Loculoascomycetes, Leptosphaeria.

scholarly journals Description of a new genus of primitive ants from Canadian amber, with the study of relationships between stem- and crown-group ants (Hymenoptera: Formicidae)

2016 ◽  
Author(s):  
Leonid H. Borysenko
Keyword(s):  
Statistical Analysis ◽  
Morphometric Analysis ◽  
New Genus ◽  
Statistical Study ◽  
The Other ◽  
Taxonomic Position ◽  
Crown Group ◽  
Stem Group ◽  
Evolution Of Eusociality

AbstractA detailed study of the holotype ofSphecomyrma canadensisWilson, 1985 from Canadian amber has led to the conclusion that the specimen belongs to a new genus, here namedBoltonimeciagen.n. Since the taxonomy of stem-group ants is not well understood, in order to find the taxonomic position of this genus, it is necessary to review the classification of stem-group ants in a study of their relation to crown-group ants. In the absence of data for traditional taxonomic approaches, a statistical study was done based on a morphometric analysis of antennae. Scape elongation is believed to play an important role in the evolution of eusociality in ants; however, this hypothesis has never been confirmed statistically. The statistical analysis presented herein lends support to the view that antennal morphology reliably distinguishes stem-group ants from crown-group ants to determine whether a species belongs to one or the other group. This, in turn, may indicate a relationship exists between eusociality and scape elongation. A review of Cretaceous records of ants is made and the higher classification of Formicidae with definitions of stem and crown groups is proposed. Newly obtained data are discussed focusing particularly on the origin, evolution and diversity of ants.

HUMAN URINARY GONADOTROPHINS ASSAYED BY DIFFERENT RESPONSES IN THE SAME ANIMAL

1960 ◽  
Vol XXXIV (III) ◽  
pp. 375-389 ◽  
Author(s):  
P. S. Brown
Keyword(s):  
Postmenopausal Women ◽  
Ovarian Response ◽  
The Other ◽  
Relative Potency ◽  
Vaginal Opening ◽  
Serial Sections ◽  
Immature Female ◽  
Female Mice ◽  
Marked Disparity ◽  
Relative Potencies

ABSTRACT Selected human urinary gonadotrophins were assayed against one another using various measures of response in the same immature female mice. Intact or hypophysectomized animals were used and in some experiments the results of hypophysectomy were checked in complete serial sections. Extracts from the urine of two subjects with Turner's syndrome were compared. In intact mice, the relative potency judged by the ovarian response differed from that shown by the uterine response and the 95 % fiducial limits of the two estimates did not overlap. When the mice were hypophysectomized, one extract became much less potent while the other did not. Similar differences were shown in the response of intact mice to urinary extracts from two subjects with Klinefelter's syndrome. There was a marked disparity between the relative potencies shown by the uterine response and by the incidence of vaginal opening. Similar differences were not shown between the responses to different extracts from the urine of normal postmenopausal women, but these extracts were known to differ little in quality. The results are interpreted in terms of qualitative differences between human urinary gonadotrophins.

HISTOPATHOLOGY OF THE PIGMENTED TUMORAL-LIKE LESIONS OF THE SKIN AT HUE HOSPITAL OF MEDICINE AND PHARMACY UNIVERSITY

2018 ◽  
Vol 8 (4) ◽  
pp. 65-69
Author(s):  
Mao Nguyen Van ◽  
Dong Tran Nam
Keyword(s):  
Key Words ◽  
Definitive Diagnosis ◽  
The Other ◽  
Cell Tumour ◽  
Cross Sectional ◽  
Skin Tumour ◽  
Clinical Appearance ◽  
The Face ◽  
The Common ◽  
Difficult Cases

Background: Pigmented tumour of the skin is one of the common tumour in human including the benign pigmented tumours (more common) called Nevi tumours and the malignant one called melanoma which was less frequent but the most poor in prognosis. In addition, the others not belonging to these group had the same clinical appearance, so the application of histopathology and immunohistochemistry for the definitive diagnosis was indespensible. Objectives: 1. To describe the macroscopic features of the pigmented tumoral-like lesions; 2. To classify the histopathologic types of the pigmented cell tumours and the other pigmented tumours of the skin. Materials and Method: Cross-sectional research on 55 patients diagnosed as pigmented tumoral lesions by clinician, then all definitively diagnosed by histopathology combining the immunohistochemistry in difficult cases. Results: There was no difference in gender, the disease was discovered most common in adult, especially with the age over 51 years old (58.1%). the most region located was in the face accounting for 60%, following the trunk and limbs (14.6%, 12.8% respectively). All 3 malignant melanomas happened in foot. The most common color of the lesions was black (65.4%), the other ones were rose, grey and blue. Histopathology and immunohisthochemistry showed that the true pigmented cell tumours were 52.6% encompassing benign ones (Nevi tumour) (41.8%), melanoma (5.4%) and lentigo (5.4%). 47.4% was not the true pigmented cell tumour including pigmented basocellular carcinoma (36.4%) and the others less common as histiofibromas, acanthoma and papilloma. Conclusion: the pigmented tumoral-like lesions of the skin could be the true pigmented cell tumours and the others, so the application of the histopathology and the immunohistochemistry after the clinical discovery helps to determine and classify the disease definitely and for the best orientation of treatment as well. Key words: skin tumour, benign pigmented tumour (Nevi), malignant pigmented tumour (melanoma), pigmented basocellular carcinoma

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