scholarly journals Morphological Traits of the Radula in Viviparidae (Mollusca, Caenogastropoda) as a Master Key to Discrimination of Closely Related Species

2013 ◽  
Vol 47 (2) ◽  
pp. 40-51 ◽  
Author(s):  
V. V. Anistratenko ◽  
Yu. S. Ryabceva ◽  
E. V. Degtyarenko

The radula morphology and variability in four European species of the family Viviparidae viz. Viviparus viviparus (Linnaeus, 1758), V. sphaeridius (Bourguignat, 1880), V. ater (Cristofori et Jan, 1832) and Contectiana listeri (Forbes et Hanley, 1853) were examined using scanning electron microscopy (SEM). Statistical methods reveal a certain value of rachidian tooth dimensional parameters as an efficient tool for taxonomy and discrimination of closely related species of the family.

2021 ◽  
Vol 64 (1) ◽  
pp. 55-69
Author(s):  
Eduardo A. Morales ◽  
Carlos E. Wetzel ◽  
Luc Ector ◽  
Bart Van de Vijver

Abstract The genus Opephora currently contains 37 species and 27 infraspecific taxa. However, the existing literature reveals a wide morphological diversity and the need to establish defining characters to circumscribe the genus as a cohesive and, perhaps, monophyletic group. The type material of Opephora pacifica, the generitype, is analysed. We emend the description of both the species and the genus, the latter also based on published light and scanning electron microscopy observations of closely related species. After review of the available literature, we determined that currently only two species can be ascribed with certainty to the genus Opephora: O. pacifica and O. marina. Based on available literature, it is highly likely that O. fragilarioides also belongs to this genus. We present a table with all known species and infraspecific taxa and make comments regarding their recent transfer to other genera, their current accepted nomenclature, and the genus to which they should probably be ascribed pending the collection of further information.


PeerJ ◽  
2018 ◽  
Vol 6 ◽  
pp. e5028 ◽  
Author(s):  
Débora A. Carvalho ◽  
Pablo A. Collins ◽  
Renata Lima-Gomes ◽  
Célio Magalhães ◽  
Maria Victoria Torres ◽  
...  

The gastric armature of decapod foregut is a feeding structure that sparks controversial debates about the role dietary and historical components have in shaping its morphological traits. Having previous information about the natural diet is an interesting way to gather evidence on this issue. For the present study, we analyzed the morphological traits of gastric ossicles involved directly in the maceration of food in nine species of freshwater crabs of the family Trichodactylidae (Brachyura: Decapoda) representing five genera, three tribes and two subfamilies. The analyzed gastric ossicles were quite consistent among closely related species, suggesting that the observed traits had a clear phylogenetic component. However, it was also noted that the morphological traits of the gastric teeth of trichodactylid crabs match well with the natural diet and presented likeness with general features of other species with a similar trophic habit. We discuss the influence of phylogeny and function on the design of morphological traits and propose to quantify the role of phylogeny and function in shaping morphological traits through the analysis of phylogenetic signals.


1979 ◽  
Vol 57 (2) ◽  
pp. 91-99 ◽  
Author(s):  
D. L. Hawksworth

Generic concepts in the Testudinaceae (Ascomycotina, Loculoascomycetes) are reviewed with particular emphasis on the sculpturing of the ascospores which has been examined by scanning electron microscopy (SEM) for the first time. A key to the nine genera accepted in the family is provided of which two are described as new: Ulospora for U. bilgramii comb.nov. (= Zopfia bilgramii D. Hawksw. et al.), the ascospores of which have three to six deep fissures in each cell, and Zopfiofoveola for Z. punctata comb.nov. (= Zopfia punctata D. Hawksw. & C. Booth), with distinctly and regularly foveolate ascospores. One further new combination is made: Rechingeriella boudieri comb.nov. (= Zopfia boudieri Arnaud). The positions of three additional genera referred to the family by earlier authors but which are excluded from it here are also briefly discussed.


2020 ◽  
Vol 94 ◽  
Author(s):  
O.M. Amin ◽  
M. Sharifdini ◽  
R.A. Heckmann ◽  
M. Zarean

We describe morphological features not previously reported for this old acanthocephalan Nephridiacanthus major (Bremser, 1811 in Westrumb, 1821) Golvan, 1962 first described over 200 years ago. Our specimens were collected from long-eared hedgehog Hemiechinus auritus (Gmelin, 1770) (Erinaceidae) in Iran. We compare the morphometrics of our material with others previously reported from the same host in Iran, Russia, central Asia and Europe. Our specimens had markedly smaller proboscides, proboscis hooks and lemnisci than those reported from Russia and central Asia, but comparable measurements of other structures with specimens previously described from other collections. We document our new observations with scanning electron microscopy features not previously demonstrable by other observers and provide a chemical analysis of proboscis hooks using energy-dispersive X-ray analysis for the first time. The molecular profile of this acanthocephalan, based on 18S rDNA and cox1 genes, was generated for the first time. The phylogenetic analysis showed that N. major is placed in a clade of the family Oligacanthorhynchidae, well separated from the families Moniliformidae and Gigantorhynchidae.


Author(s):  
M Pezzi ◽  
C Scapoli ◽  
M Bharti ◽  
M J Faucheux ◽  
M Chicca ◽  
...  

Abstract A relevant species in waste management but also in forensic, medical, and veterinary sciences is the black soldier fly, Hermetia illucens (Linnaeus; Diptera: Stratiomyidae). An ultrastructural study by scanning electron microscopy (SEM) was conducted for the first time on maxillary palps of both sexes, describing in detail the morphology and distribution of sensilla and microtrichia. The maxillary palps, composed of two segments, show sexual dimorphism in length and shape. In both sexes, the first segment is covered only by microtrichia, but the second one is divided into two parts: the proximal one, covered only by microtrichia, and the distal one containing both microtrichia and sensory structures. These structures include two types of sensory pits and one of chaetic sensilla. Due to sexual dimorphism in palp size, females have a higher number of sensory pits. The sexual dimorphism of palps and the presence and role of sensilla in H. illucens was discussed in comparison to other species of the family Stratiomyidae and of other Diptera. This study may represent a base for further investigations on mouthpart structures of this species, involved in key physiological activities, such as feeding, mating and oviposition.


Mammalia ◽  
2019 ◽  
Vol 83 (6) ◽  
pp. 601-609
Author(s):  
Pablo Teta ◽  
María Carolina Madozzo-Jaén ◽  
Alexandra M.R. Bezerra ◽  
Pablo E. Ortiz ◽  
Sergio O. Lucero ◽  
...  

Abstract The genus Galea Meyen, 1833 includes at least five species of terrestrial, diurnal and herbivorous cavies that occupy grasslands and rocky scrub areas at both high and low elevations in South America. According to the available molecular and morphological data, Galea comes Thomas, 1919 is restricted to highland areas above 2000 m in southern Bolivia and northwestern Argentina. Its distributional range as well as its morphological distinctiveness from other closely related species (Galea leucoblephara and Galea musteloides) is poorly documented. Using both qualitative and quantitative morphological traits, we provided an emended diagnosis for G. comes. In addition, we added six new locality records to its known distribution.


Zootaxa ◽  
2019 ◽  
Vol 4619 (3) ◽  
pp. 401-430 ◽  
Author(s):  
NESTOR FERNANDEZ ◽  
PIETER THERON ◽  
SERGIO LEIVA ◽  
ANINE JORDAAN

Diplobodes africanus Mahunka, 1987, is redescribed by using Scanning Electron Microscopy (SEM) in order to complement optical microscopy. Diplobodes thailande sp. nov. from Thailand is described. For both species we include inclined views, to permit detailed analysis of ventral regions and to aid understanding of the complex relationships between elevated and depressed zones. Diplobodes thailande sp. nov. presents previously undescribed structures on legs III, which are involved in the leg folding process. Rwandabodes kayoveae gen. nov., sp. nov. presents a series of particular characteristics, such as: elevated interlamellar process on prodorsum, composed of a triangular structure, externally delimited by a low lamellar furrow; in setae inserted on elevated interlamellar process; large free lamellar tip; notogaster lacking ridges; anterior genital furrow extends into an oblique lateral depression; depressed area anterior to anal zone; both zones clearly delimited. These characteristics permit easy differentiation from related genera. 


1971 ◽  
Vol 49 (8) ◽  
pp. 1259-1261 ◽  
Author(s):  
Larry F. Grand ◽  
Royall T. Moore

Basidiospores of 13 North American species of Strobilomycetaceae were examined by scanning electron microscopy. Similarities and differences of surface features among species are discussed in relation to their possible role in the taxonomy of the family.


1994 ◽  
Vol 68 (4) ◽  
pp. 319-322 ◽  
Author(s):  
F. Moravec ◽  
A. Kohn ◽  
B.M.M. Fernandes

AbstractThe cephalic end of the type species of pharyngodonid genera Travnema and Cosmoxynemoides, T. travnema Pereira, 1938 and C. aguirrei Travassos, 1949, parasites of Brazilian freshwater fishes, was studied by scanning electron microscopy. The mouth aperture of Travnema was found to be circular, surrounded by four cephalic papillae and two lateral amphids and the cuticle of the cephalic end had a conspicuous dense sculpture. On the other hand, the mouth aperture of Cosmoxynemoides was triangular, surrounded by three lip-like elevations covering the whole surface of the relatively flat cephalic extremity, each with two inner lobes separated one from another by a short groove; the lip-like elevations bore four medium-sized, kidney-shaped cephalic papillae and two minute amphids (two papillae on the dorsal elevation and one papilla and one amphid on each of two ventrolateral elevations); the cuticle of the cephalic end was smooth. Both species were noted for the absence of oral lamellae and the presence of lateral alae. Both genera are listed in the family Pharyngodonidae but Travnema (and also Hakynema), due to its morphological peculiarities, is considered to represent a distinct subfamily Travnematinae within the Pharyngodonidae. The finding of both T. travnema and C. aguirrei in the characid fish Astyanax bimaculatus lacustris represents new host records.


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