scholarly journals Morfometría geométrica del borde corial y del collar de huevos de cinco especies del género Rhodnius Stal (Heteroptera, Reduviidae, Triatominae)

2008 ◽  
Vol 1 (3) ◽  
pp. 57-61 ◽  
Author(s):  
Ximena Páez-Colasante ◽  
Elis Aldana

Resumen. La taxonomía y sistemática de la subfamilia Triatominae (Heteroptera, Reduviidae) se basan principalmente en caracteres biométricos y morfológicos de las formas adultas y, en algunos casos, de las ninfas. La Morfometría Geométrica es capaz de descomponer la forma en sus componentes tamaño isométrico y conformación. En el presente trabajo se utilizó la Morfometría Geométrica como herramienta de análisis de la configuración geométrica que resulta de la unión de los extremos del borde corial y del collar (configuración borde corial-collar) de los huevos eclosionados de cinco especies del género Rhodnius Stal. Los huevos se observaron por Microscopía Electrónica de Barrido y las imágenes digitalizadas fueron analizadas morfogeométricamente. Estudiando el tamaño geométrico de la configuración borde corial-collar, se halló que no existen diferencias estadísticamente significativas entre las cinco especies de Triatominos. En cuanto a la conformación, se determinaron diferencias entre las especies al ser sometidas a un análisis discriminante. Se encontró además que la variación del tamaño contribuye a la variación en la conformación, es decir, efecto alométrico. Los resultados obtenidos indican que la conformación de la configuración geométrica “borde corial-collar” de los huevos de Rhodnius podría ser utilizada como herramienta taxonómica para este grupo.   Morfometria geométrica da borda corial e colarinho de ovos de cinco espécies do Gênero Rhodnius (Heteroptera Reduviidae, Triatominae). Resumo. A taxonomia e sistemática da subfamília Triatominae (Heteroptera Reduviidae) esta baseada principalmente em caracteres biométricos e morfológicos das formas adultas, e em alguns casos, das ninfas. A morfometria geométrica é capaz de descompor a forma em seus componentes, tamanho isométrico e conformação. No presente trabalho utilizou-se a morfometria geométrica como ferramenta de análise da configuração geométrica que resulta da união dos extremos da borda corial e “colarinho” (configuração borda corial-colarinho) dos ovos eclodidos de cinco espécies do gênero Rhodnius. Os ovos observaram-se por meio de Microscopia Eletrônica de Varredura (MEV) e as imagens digitais foram analisadas morfogeometricamente. Estudando o tamanho geométrico da configuração borda corial-colarinho, consiguiu-se que não existem diferenças estatisticamente significativas entre as cinco espécies de Triatomineos. Quanto à conformação, determinaram-se diferenças entre as espécies ao ser submetidas a uma análise discriminante. Além de isso encontrou-se que a variação do tamanho contribui à variação na conformação, ou seja, efeito alométrico. Os resultados obtidos indicam que a morfogeometria da borda corial e do “colarinho” dos ovos de Rhodnius poderia ser utilizada como uma ferramenta taxonômica para este grupo.   Geometric morphometrics of the chorial rim and the collar of the eggs of five species of the Rhodnius genus (Heteroptera, Reduviidae, Triatominae). Abstract. The taxonomy and systematics of the Triatominae subfamily are based primarily on the biometric and morphological characters of the adult forms, and in some cases of the nymphs. Geometric Morphometrics are capable of separating the form in its components size and shape. In this work Geometric Morphometrics were used as a tool for the analysis of the chorial rim and the collar of hatched eggs of five species of the Rhodnius genus. Collected eggs were observed by Scanning Electron Microscopy and the digitalized images were analyzed by Generalized Procrustes Analysis. By studying the isometric size of the chorial rim and the collar, no statistical significant differences were found among the five species of Rhodnius genus. A discriminant analysis showed statistical differences among the shapes of the chorial rim and the collar, indicating that the shape is a species specific character. An allometric effect was found. The results obtained indicate that the geometric morphometrics of the chorial rim and the collar of hatched Rhodnius eggs can be used as a taxonomic tool for this group.    

Phytotaxa ◽  
2021 ◽  
Vol 502 (2) ◽  
pp. 191-207
Author(s):  
SHIVANI KASHYAP ◽  
CHANDAN KUMAR SAHU ◽  
ROHIT KUMAR VERMA ◽  
LAL BABU CHAUDHARY

Due to large size and enormous morphological plasticity, the taxonomy of the genus Astragalus is very complex and challenging. The identification and grouping of species chiefly based on macromorphological characters become sometimes difficult in the genus. In the present study, the micromorphology of the seeds of 30 species belonging to 14 sections of Astragalus from India has been examined applying scanning electron microscopy (SEM) along with light microscopy (LM) to evaluate their role in identification and classification. Attention was paid to colour, shape, size and surface of seeds. The overall size of the seeds ranges from 1.5–3.2 × 0.8–2.2 mm. The shape of the seeds is cordiform, deltoid, mitiform, orbicular, ovoid and reniform. The colour of seeds varies from brown to blackish-brown to black. Papillose, reticulate, ribbed, rugulate and stellate patterns were observed on the seed coat surface (spermoderm) among different species. The study reveals that the seed coat ornamentations have evolved differently among species and do not support the subgeneric and sectional divisions of the genus. However, they add an additional feature to the individual species, which may help in identification in combination with other macro-morphological features.


2021 ◽  
Vol 9 (10) ◽  
pp. 1386-1393
Author(s):  
Jayshree Sandesh Thaware ◽  

Pollen is appropriately referred by some as Golden dust extremely valuable on account of their tremendous applications in science, industries and public health. No other plant part even though extremely tiny in size is packed with so much information and power. Similar to other plant parts, pollen characters are so varied that the classification system of plants can be built up entirely on the basis of pollen morphology.Palynology is the distinct branch of biology that deals with the dispersed microscopic tiny living and fossil entities including pollen grains, spores, algal and fungal fragments and others. An important aspect of Palynology is the Pollen morphology. The importance of Palynology in taxonomic and phylogenetic consideration of plants is well known. The changes occurring through hybridization and years of cultivation are reflected in pollen morphology. The scope and interest in the study of pollen morphology have widened with the advent of Scanning Electron Microscopy (SEM) and with regards to unipalynous taxa particularly the understanding of finer morphology is of fundamental importance. SEM gives a correct understanding of exine surface as the electron photographs of the surface replica of the exine provides the exact picture of the ornamentation pattern. The variation in the pollen morphological characters helps in the classification of plant taxa and their assessment of their phylogenetic relationship. In the present investigation, the pollen morphological studies were carried out of some ethnomedicinal plants like Catharanthus roseus, Allamanda cathartica, Datura metel, Brassica juncea, Raphanus sativus and Cleome viscosa pollen grains by Scanning electron microscopy. All that they possess anticancer characteristics in common.


Zootaxa ◽  
2011 ◽  
Vol 2970 (1) ◽  
pp. 33 ◽  
Author(s):  
CLAUDIA M. SANDOVAL ◽  
ELSA NIEVES ◽  
VÍCTOR M. ANGULO ◽  
JOÃO ARISTEU DA ROSA ◽  
ELIS ALDANA

The external morphology of eggs of the species Belminus corredori Galvão & Angulo, 2006, Belminus herreri Lent & Wygodzinsky, 1979 and Belminus ferroae Sandoval, Pabón, Jurberg & Galvão, 2007 is described for the first time using scanning electron microscopy (SEM). Females lay one egg at a time; the shape of the egg is oval with lateral flattening, a rounded caudal area and a true and simple convex operculum. The average size of the egg among these species is 0.51– 0.58 mm in length and 0.36–0.4 mm in width. As a generic character we highlight the discovery of a chorion rim with one to four grooves always joined to the micropyles. All species present a clear polygonal pattern only in the operculum and in the egg’s cephalic region, while the median and caudal regions show a smooth appearance, features that are shared only with the eggs of the genus Alberprosenia. A discriminant analysis of the polygonal design of the operculum proved to be useful for the identification of the species.


2000 ◽  
Vol 6 (S2) ◽  
pp. 872-873
Author(s):  
James R. Rosowski ◽  
Terry L. Bartels ◽  
James F. Colburn ◽  
Jannell L. Colton ◽  
Denton Belk ◽  
...  

Tadpole shrimp inhabit temporary freshwater pools and ponds where their occurrence is largely regulated by rainfall events and water temperature. When dry basins are flooded, cysts of Triops imbibe water and hatch to produce rapidly growing, carapaced larvae. While previous studies show anostracan (fairy shrimp) cyst-surface morphology often species specific, few studies illustrate shell ultrastructure of Triops and none has considered T. longicaudatus. Here we examine the shell of T. longicaudatus (Notostraca) and compare its fine structure to other species of Triops and to that of Artemiafranciscana(Anostraca), which we previously studied.Cysts, produced in culture from Utah broodstock, were purchased from Triops, Inc., 1924 Creighton Rd., Pensacola, FL 32504. Thin sections of cysts were prepared for transmission electron microscopy (TEM) as previously described (Fig. 1). Cysts were also examined with scanning electron microscopy (SEM), dry, whole or fractured (Figs. 2,3), or after imbibition and/or hatching in oxygen saturated, double-distilled water, at 25 ° C.


2013 ◽  
Vol 20 (1) ◽  
pp. 85-94 ◽  
Author(s):  
Huan-Fang Liu ◽  
Yun-Fei Deng ◽  
Jing-Ping Liao

Foliar trichomes of 21 species of the genus Croton L. from China have been examined using stereomicroscopy and scanning electron microscopy. Five trichome types characterized by their morphology are identified, viz., stellate, lepidote, simple, dendritic and appressed-rosulate. Only stellate trichome is observed in most species, with only six species that are found to maintain two or three trichome types. Trichome types and density are useful for species identification and sectional classification for Chinese species. Based on the trichome types and other morphological characters, 21 Chinese species are proposed to be placed in five sections. Croton crassifolius belongs to sect. Andrichnia; C. cascarilloides belongs to sect. Monguia; C. mangelong, C. kongensis, C. laevigatus and C. laniflorus belong to sect. Argyrocroton; C. lauioides, C. howii and C. damayeshu belong to sect. Adenophylli. The remaining Chinese Croton species might be placed into sect. Croton. A key for Chinese Croton species based on trichome morphology is provided.DOI: http://dx.doi.org/10.3329/bjpt.v20i1.15468Bangladesh J. Plant Taxon. 20(1): 85-94, 2013 (June)


2018 ◽  
Vol 25 (2) ◽  
pp. 175-186 ◽  
Author(s):  
Changyoung Lee ◽  
Jinki Kim ◽  
Ashwini M. Darshetkar ◽  
Ritesh Kumar Choudhary ◽  
Sang-Hong Park ◽  
...  

Mericarp morphology of 24 taxa belonging to nine genera of the tribe Selineae (Family: Apiaceae) in Korea was studied by Scanning Electron Microscopy. UPGMA and NMDS analyses were performed based on 12 morphological characters. The mericarp surface characters like mericarp shape, rib number and shape, surface pattern, surface appendages and mericarp symmetry proved useful in distinguishing the genera of the tribe Selineae.


Zootaxa ◽  
2010 ◽  
Vol 2493 (1) ◽  
pp. 16 ◽  
Author(s):  
IVO DE SENA OLIVEIRA ◽  
ALFREDO HANNEMANN WIELOCH ◽  
GEORG MAYER

Based on the supposed quadrangular shape of the basal pieces of dorsal primary papillae, several species of the “Caribbean group” of the neotropical Peripatidae, including Macroperipatus acacioi and M. machadoi, were assigned to Macroperipatus. So far, the quadrangular shape of dermal papillae was confirmed only for M. torquatus, the type species of the genus. Previous observations revealed that the putatively quadrangular shape reported from other species of the “Caribbean group” might be a fixation artefact. Hence, detailed reinvestigations of all putative Macroperipatus species are required to clarify their taxonomy. In the present study, two species of the “Caribbean group”, M. acacioi and M. machadoi, are analyzed and redescribed, based on type material and topotype specimens collected at the corresponding type localities. The original descriptions of both species are complemented with data obtained from scanning electron microscopy, in addition to conventional morphological methods. The quadrangular bases of primary papillae are shown to be absent from M. acacioi and M. machadoi, thus suggesting that these two species are not closely related to M. torquatus. The new data instead suggest that these two species are representatives of Epiperipatus: E. acacioi comb. nov. and E. machadoi comb. nov.. The present study highlights the use of scanning electron microscopy for clarifying the taxonomy and phylogeny of the neotropical Peripatidae. It also reveals gaps in taxon sampling and problems regarding the ambiguous terminology of morphological characters used for describing the anatomy of peripatids. An attempt is made towards a consistent terminology for species (re)descriptions and studies of onychophoran anatomy and phylogeny.


2015 ◽  
Vol 58 (1) ◽  
Author(s):  
Sergio Escobar-Morales ◽  
David U. Hernández-Becerril

AbstractThe so-called unarmoured dinoflagellates are not a “natural” (phylogenetic) group but they lack thecal plates, share fragility and possess relatively few morphological characters that can be positively identified. This study depicts the species composition of unarmoured dinoflagellates collected from sites along the coasts of the Gulf of Mexico and the Mexican Pacific and includes their descriptions and illustrations. We identified a total of 25 species belonging to 13 genera and six families that were studied through various techniques using light and scanning electron microscopy. Seven new records for the Mexican Pacific are annotated here that include


1971 ◽  
Vol 19 (2) ◽  
pp. 173 ◽  
Author(s):  
SGM Carr ◽  
L Milkovits ◽  
DJ Carr

The eucalypt leaf contains a store of untapped information of potentially great value taxonomic and evututionary studies. Tie cuticie of certain eucalypts is shown to possess a complex and species-specific ornamentation so distinctive that its features can be regarded as diagnostic. The term "phytoglyph" is coined for the constellation of microanatomical features of the surfaces of leaves, including the microanatomy of the cuticle. Phytoglyphic analysis relates to the combination of three methods, light microscopy of stained cuticles, scanning electron microscopy of leaf surfaces, and light microscopy of thin sections of the cuticular and associated structures. Its use is illustrated by the dissection of the "form species" E. dichromophloia into a number of separate and recognizable entities, some of which were previously accorded the status of species. The plant geographical and other implications of this dissection are dealt with. In particular, E. dichromophloia F. Muell. is to be regarded as a species of very restricted distribution. The microanatomical characters of the cuticle are closely controlled products of the epidermal layers. The fact that specimens which (on other grounds) can be grouped together as a species have identical cuticular microanatomy suggests that the phytoglyph is genetically strongly determined and does not consist of inadvertent, trivial surface features with a high degree of plasticity. This in turn raises the problem of the development of the cuticular microanatomy which cannot be explained on current views of the formation of the cuticle by passive diffusion of precursor substances through the epidermal walls, followed by a hardening process.


2013 ◽  
Vol 5 (2) ◽  
pp. 201-208
Author(s):  
Pamela Murillo ◽  
Hugo Aguilar ◽  
Ethel Sanchez

Scanning electron microscopy (SEM) has been used as a tool to facilitate the morphological description of mites and to complement the information obtained from the light microscope. Unfortunately, several of SEM techniques used for soft-bodied mites such as Tyrophagus, have in many cases not shown the desired results. This investigation sought to develop an efficient procedure for preparing specimens of T. putrescentiae for SEM so that its major morphological characters could be observed and photographed. This species is the most important contaminant of tissue culture laboratories in Costa Rica. Seven methods were used to process the samples. The evaluated treatments showed differences in their ability to preserve the morphological structures of the specimens. The advantages and disadvantages of each treatment are discussed.  Mites processed using ethanol were the most viable option with method 3 being the procedure that showed the best results; this technique also reduced the time and costs of processing the specimens.KEY WORDSAcari, Acaridae, Tyrophagus putrescentiae, Scanning Electron Microscopy (SEM), SEM techniques


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