New data on the morphology of Comephoronema oschmarini (Nematoda, Cystidicolidae), a little-known gastrointestinal parasite of Lota lota (Teleostei) in Palaearctic Eurasia

2007 ◽  
Vol 52 (2) ◽  
Author(s):  
František Moravec ◽  
Vladimíra Hanzelová ◽  
Daniel Gerdeaux

AbstractThe nematode Comephoronema oschmarini Trofimenko, 1974 (Cystidicolidae) was found in the stomach of the burbot Lota lota (Linnaeus) of Lake Geneva, Savoy, France, collected on 23 March 2000 [prevalence 60% (3/5); intensity of infection 2–66 (mean 35)]. This material made it possible to study in detail the morphology of this so far little-known parasite, using both light and scanning electron microscopy (the latter not previously used for this species). The SEM examination showed taxonomically important morphological features, not previously reported, including the presence of distinct terminal pseudolabial projections (protuberances), four submedian labia, four bilobed submedian sublabia, and only four cephalic papillae. Deirids were found to be bifurcated. A description of the true arrangement of the two last pairs of minute caudal papillae and phasmids in the male is given. Species of Compehoronema Layman, 1933 are considered to be closely related to those of Ascarophis van Beneden, 1871. A key to valid species of Comephoronema is provided.

Biologia ◽  
2008 ◽  
Vol 63 (4) ◽  
Author(s):  
Patrycja Boszke ◽  
Mariusz Pełechaty ◽  
Andrzej Pukacz

AbstractMorphological features of oospores of a rarely noted species Chara braunii Gmel. were examined in a local population (fishpond near Tuplice village, Ziemia Lubuska region, mid-western Poland). The largest polar axis (LPA, length), largest equatorial diameter (LED, width), isopolarity index (ISI = LPA/LED* 100), and the number of ridges and width of fossa of 90 oospores were measured. Additionally, the oospore wall ornamentation pattern was examined by means of scanning electron microscopy (SEM). As a result, a cylindrical shape and the lack of so-called “shoulder” were found. Oospore length and width ranged between 466.8–600.1 µm and 250.1–366.7 µm, respectively, with the ISI index values between 148 and 213. The number of ridges was 8–10 and the width of fossa varied between 50.0 and 66.7 µm. The oospore width appeared to be the most changeable feature, whereas, by contrast, the number of ridges was the least variable character. Wall ornamentation can be described as tuberculate and a ribbon was present on the ridges. As a comparative material for the study performed, 9 oospores from Professor Izabela Dąmbska’s Collection of Charophytes of Poland were measured. It was evidenced that variation ranges of most of the features of Chara braunii oospores from Tuplice fishpond are similar to those of Professor Dąmbska’s herbarium materials and to data reported by authors from other countries as well. The morphology of reproductive structures does not follow the variation of thalli characteristics.


Phytotaxa ◽  
2020 ◽  
Vol 453 (3) ◽  
pp. 179-198
Author(s):  
ANBUKKARASU VIGNESHWARAN ◽  
CARLOS E. WETZEL ◽  
DAVID M. WILLIAMS ◽  
BALASUBRAMANIAN KARTHICK

Tabularia (Kützing) D.M. Williams & Round has received some attention since its separation from Synedra. The present study investigates Fragilaria fonticola Hustedt and its varieties based on the analysis of the type materials. The combinations were proposed as Tabularia fonticola (Hustedt) C.E. Wetzel & D.M. Williams comb. nov. (≡ Fragilaria fonticola Hustedt), Tabularia angusta (Hustedt) C.E. Wetzel & D.M. Williams comb. nov. et stat. nov. (≡ Fragilaria fonticola var. angusta Hustedt), Tabularia chandolensis (Gandhi) A. Vigneshwaran, D.M. Williams & B. Karthick comb. nov. (≡ Synedra chandolensis Gandhi) and the new species, Tabularia koynensis sp. nov. is also described from the Koyna River basin, Western Ghats, India. The detailed morphological features were analysed under light and scanning electron microscopy. Tabularia koynensis has linear valves outline with square to rounded ends. Striae short, radiate towards ends. This new species compared with T. sinensis, T. fasciculata, T. tabulata, T. kobayasii and Fragilaria longissima, which differ in size, valve shape, striae density and ultrastructure.


Zootaxa ◽  
2006 ◽  
Vol 1122 (1) ◽  
pp. 57 ◽  
Author(s):  
MICHAEL W. HASTRITER ◽  
KATHARINA DITTMAR ◽  
MICHAEL F. WHITING

Endoparasitic dealate females of Ascodipteron and an undescribed genus of Ascodipterinae are examined by scanning electron microscopy. The unique morphology of the head and mouth parts and terminal segments are displayed and discussed. Prior reports have focused only on details observable with light microscopy. The taxonomic position of members of the subfamily Ascodipterinae relative to the Old World families of Streblidae and Nycteribiidae is briefly discussed in light of previously published molecular information.


2011 ◽  
Vol 31 (1-2) ◽  
pp. 98-102 ◽  
Author(s):  
Gustavo Ferreira Martins ◽  
José Marcelo Ramalho-Ortigão ◽  
Paulo Filemon Paolucci Pimenta

Phytotaxa ◽  
2017 ◽  
Vol 331 (2) ◽  
pp. 169 ◽  
Author(s):  
KAMİL COŞKUNÇELEBİ ◽  
SERDAR MAKBUL ◽  
SEDA OKUR

Macro- and micro-morphological features of seeds belonging to 26 taxa from Turkey were observed under the light and scanning electron microscopy. Present findings partly agree with segregation of Epilobium and Chamerion at generic level. The members of the genus Epilobium were distinguished by seeds with conical, semispherical, cylindrical or crest-like papillae or without papillae, granulate periclinal surfaces, papillae with parallel, radial, irregular or spirally furrow and the members of Chamerion were distinguished by seeds crest-like papillae or without papillae and without granulate periclinal surfaces and without furrow. The results also showed that seed shape, presence/absence of papillae and beak, papillae shape and ornamentation, and periclinal wall features are valuable for delimiting the examined taxa specific level within both genera. A key to Turkish Epilobium and Chamerion taxa based on seed morphology is presented for the first time


Check List ◽  
2016 ◽  
Vol 12 (1) ◽  
pp. 1834 ◽  
Author(s):  
Alexandre Gonçalves dos Santos Silva-Filho ◽  
Gilberto Coelho ◽  
Vagner Gularte Cortez

Neopaxillus echinospermus is a common but poorly understood agaric species from South America (Argentina, Bolivia, Brazil and Paraguay). In this paper, we discuss conflicting morphological features reported in the literature and expand the distribution of the species to Seasonal Deciduous and Semideciduous Forests from Rio Grande do Sul and Paraná states, respectively, in Southern Brazil. Hyphal structure of the pileipellis, presence of cheilocystidia and caulocystidia, presence of clamp connections and oleiferous (thrombopleurous) hyphae, and the basidiospore morphology under scanning electron microscopy are illustrated and discussed in detail.


2014 ◽  
Vol 23 (2) ◽  
pp. 251-254
Author(s):  
Estevam Guilherme Lux Hoppe ◽  
José Hairton Tebaldi ◽  
Daniel Fontana Ferreira

The genus Habronema has four valid species, of which only two are properly known. The present study aimed to describe in detail the morphology of Habronema clarki through optical and scanning electron microscopy analyses. Our results showed that the labial morphology of this parasite is closer to H. muscae than to H. microstoma. Even so, the characteristic pseudolabia and the slightly convex border of the dorsal and ventral lips are sufficient to distinguish these nematodes. Additional morphological data are presented, thus contributing to the knowledge on this little known nematode. In addition, this study provides new locality records for this species.


Crystals ◽  
2020 ◽  
Vol 10 (6) ◽  
pp. 535 ◽  
Author(s):  
Min Tang ◽  
Yi-Liang Li

In this study, the crystal habits of pyrite in the volcanic hot springs from Kamchatka, Russia were surveyed using scanning electron microscopy. Pyrite crystals occur either as single euhedral crystals or aggregates with a wide range of crystal sizes and morphological features. Single euhedral crystals, with their sizes ranging from ~200 nm to ~40 µm, exhibit combinations of cubic {100}, octahedral {111}, and pyritohedral {210} and {310} forms. Heterogeneous geochemical microenvironments and the bacterial activities in the long-lived hot springs have mediated the development and good preservation of the complex pyrite crystal habits: irregular, spherulitic, cubic, or octahedral crystals congregating with clay minerals, and nanocrystals attaching to the surface of larger pyrite crystals and other minerals. Spherulitic pyrite crystals are commonly covered by organic matter-rich thin films. The coexistence of various sizes and morphological features of those pyrite crystals indicates the results of secular interactions between the continuous supply of energy and nutritional elements by the hot springs and the microbial communities. We suggest that, instead of a single mineral with unique crystal habits, the continuous deposition of the same mineral with a complex set of crystal habits results from the ever-changing physicochemical conditions with contributions from microbial mediation.


Zootaxa ◽  
2019 ◽  
Vol 4555 (2) ◽  
pp. 291
Author(s):  
ELIELTON NASCIMENTO ◽  
THAYNÃ CAVALCANTI ◽  
ULISSES PINHEIRO

Acanthella Schmidt, 1862 species are characterized by choanosomal skeleton of dendritic tracts cored by interwoven sinuously bent strongyles or strongyloxeas and echinated by straight styles, oxeas or anisoxeas (Van Soest et al. 2002). The genus Acanthella comprises 33 valid species, with six known from the Atlantic Ocean (Van Soest et al. 2018). Previously, the only record for Brazil was A. flagelliformis (Van Soest & Stentoft, 1988) (Muricy 2018). Species of the genus include a transition from shrub like ‘Axinellas’ and herbaceous species similar to the genus Suberites Nardo, 1833 (Schmidt 1862; Vosmaer 1912). Due to its heterogeneous complex of species, Acanthella has been confused with other axinellids. Similarities were seen in genera such as Phakellia (Van Soest et al. 2002), which shares spicule complement and comparable choanosomal skeletons. In the present study, we describe a new species of Acanthella from oceanographic expeditions of the northeast region of Brazil. Two specimens of Acanthella sp. nov. were collected by dredging at Ceará and Pernambuco State, Brazil. All specimens were preserved in 92% ethanol and deposited in the Porifera Collections at the Universidade Federal de Pernambuco (UFPEPOR). The taxonomic identification was carried out through analysis of spicules morphologies, using Light Microscopy (LM) and Scanning Electron Microscopy (SEM), following methods described by Hajdu et al. (2011). 


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