Scanning Electron Microscopy and Geometric Contour Morphometry for Identifying Eggs of Three Amazonian Species of Mansonia (Diptera: Culicidae)

2019 ◽  
Vol 57 (3) ◽  
pp. 745-754
Author(s):  
Francisco Augusto da Silva Ferreira ◽  
Rejane de Castro Simões ◽  
Ruth Leila Ferreira-Keppler ◽  
Jeronimo Alencar ◽  
Vera Margarete Scarpassa ◽  
...  

Abstract The eggs of three Amazonian species of the genus Mansonia (Diptera: Culicidae) were analyzed using morphological and morphometric characters. Eggs of Mansonia humeralis Dyar & Knab, 1916 were morphologically different from those of Mansonia titillans (Walker, 1848) and Mansonia amazonensis (Theobald, 1901), which were more similar to each other according to linear and geometric morphometry. A principal component analysis generated from elliptic Fourier contour data (PC1—92.6% and PC2—2.61%) indicated that Ma. amazonensis and Ma. titillans are more similar to each other than either is to Ma. humeralis. Discriminant multivariate analysis was highly accurate with only four classification errors and a 90% accuracy rate. The results indicate that the three Amazonian species can be precisely distinguished in the egg stage and that geometric morphometry based on elliptic Fourier contours is a promising method for distinguishing eggs of species of Mansonia. An identification key based on egg morphology is provided to distinguish the four Neotropical species.

2019 ◽  
Vol 26 (1) ◽  
pp. 1-12 ◽  
Author(s):  
Mehmet Cengiz Karaismailoğlu

Seed morphology and anatomy are taxonomically significant in Brassicaceae. The seed structures of Aethionema from Turkey, which include 12 taxa (Aethionema syriacum, A. froedinii, A. arabicum, A. eunomioides, A. fimbriatum, A. speciosum subsp. speciosum, A. speciosum subsp. compactum, A. saxatile, A. oppositifolium, A. iberideum, A. armenum, A. grandiflorum) were studied for knowing seed morphological and anatomical features with one-way analysis of variance, cluster analysis and principal component analysis. Seed size, shape and color were examined with stereomicroscopy.The surface patterns of seed were observed using Scanning Electron Microscopy (SEM). In addition, structure, and thicknesses of testa and endosperm were investigated anatomically. Thickness of testa and endosperm were of major significance to illustrate interspecific relations among the examined taxa.


Phytotaxa ◽  
2018 ◽  
Vol 361 (2) ◽  
pp. 168 ◽  
Author(s):  
MUTLU GÜLTEPE ◽  
SERDAR MAKBUL ◽  
SEDA OKUR ◽  
KAMİL COŞKUNÇELEBİ

The pollen morphology of 25 Tragopogon L. taxa (including four subspecies and four varieties) distributed in Turkey was studied under light and scanning electron microscopy. It was observed that pollen grains of the examined Tragopogon taxa are suboblate and oblate-spheroidal in shape, and 3-zonocolpororate with fifteen lacunae. The lenghts of the polar axes and equatorial axes range from 31.57 to 40.35 µm and 35.32 to 44.65 µm, respectively. Numerical analyses show that the length of equatorial axis and the pore length are the most valuable characters among nineteen palynological traits for separating the examined taxa. The general palynological characteristics of the examined taxa allow some taxonomical evaluations for the genus. However, the results of cluster and principal component analyses did not support the division of the genus at any subgeneric level; neither did the ligule colour, as reported in the literature.


1986 ◽  
Vol 64 (9) ◽  
pp. 1994-1997 ◽  
Author(s):  
M. El Gohary ◽  
M. Y. Kamel ◽  
M. H. Madbouly

External egg morphology of the camel tick Hyalomma dromedarii was studied. Injection of egg-laying females with 1% trypan blue resulted in incorporation of vital stain in the oviposited eggs. Daily measurements of fresh eggs revealed changes in egg length and width during embryonic development. Scanning electron microscopy showed the outermost layer of the egg to be spongy and porous containing clear pits of different sizes. An elevated longitudinal hatching ridge encircled the egg chorion. The development of cephalothorax, appendages, Malpighian tubules, and rectal sacs were monitered.


1995 ◽  
Vol 26 (4) ◽  
pp. 425-438 ◽  
Author(s):  
Rudolf Meier

AbstractThe eggs of 21 species in 12 genera of Sepsidae were studied using scanning electron microscopy. All but the eggs of Ortalischema have respiratory filaments which aid in gas exchange. Judged by positional differences and the lack of a central canal, the two filaments of Orygma are not homologous to the single filament of most remaining sepsids. Hinton's hypothesis that egg filaments are plesiomorphic for the Sepsidae is therefore rejected. Three egg characters are added to an existing data set comprising 58 taxa and 85 larval and adult characters. The egg characters allow the unambiguous placement of Lasionemopoda, for which the larval and adult data set had suggested two different positions on equally parsimonious trees. Based on the position of Lasionemopoda, the evolution of the fore femora of the Sepsidae is briefly discussed. The egg morphology of the Sepsidae is also compared to the morphology of drosophiline eggs which also have egg filaments.


Zootaxa ◽  
2007 ◽  
Vol 1465 (1) ◽  
pp. 15-29 ◽  
Author(s):  
NICOLÁS UBERO-PASCAL ◽  
M. ANGELS PUIG

The chorionic patterns of Ephemeroptera eggs are very diverse and these have often been used for taxonomic and systematic purposes. In a great number of species, including Potamanthus luteus, Ephemera danica and Oligoneuriella rhenana, these egg features have been studied using light microscopy. However, current trends in egg morphology studies use scanning electron microscopy (SEM), so that the eggs of these species need to be re-described in order to establish morphological comparisons. The general chorionic features which have already been described in these three species are confirmed in our SEM study, although a more detailed description of both the architecture and arrangement of these can now be offered. In addition, this study has allowed us to note new morphological data, such as the chorionic reticulation in P. luteus and the complex extrachorion-adhesive layer in E. danica; classification of the lateral attachment structure in P. luteus and O. rhenana has been changed; and the variability of the polar cap observed in P. luteus underlines the care that must to be taken when selecting chorionic structures for taxonomic purposes.


2016 ◽  
Vol 91 (2) ◽  
pp. 244-254 ◽  
Author(s):  
N.B. Ederli ◽  
F.C.R. Oliveira

AbstractThe family Deletrocephalidae consists of three species, from two genera: Deletrocephalus dimidiatus, D. cesarpintoi and Paradeletrocephalus minor, which differ from one another in terms of the buccal capsule structure, the dorsal ray from the male copulatory bursa and the length of the vagina in the female. All these species are parasites of the gastrointestinal tract of the rhea, Rhea americana. Only D. dimidiatus was reported to be a parasite of the other rhea species, Darwin's rhea, R. pennata. Currently, there are no studies on the ultrastructure and biology of these parasites or their pathogenicity in these birds. Thus, the present study aimed to examine the ultrastructure and add more details of the morphology of D. dimidiatus from R. americana. Four adult rheas were necropsied, and the gastrointestinal tract was collected and examined for the presence of parasites. Nematodes were analysed by optical and scanning electron microscopy (SEM). All birds were parasitized by D. dimidiatus. Some morphological and morphometric characters were observed that differ from reports of other studies of this species by other authors. In addition, new details were added, well described by SEM, and a key to the species of the subfamily Deletrocephalinae is given.


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