scholarly journals Multivariate analysis of anatomical characters confirms the differentiation of two morphologically close species, Melanohalea olivacea (L.) O. Blanco et al. and M. septentrionalis (Lynge) O. Blanco et al.

2009 ◽  
Vol 41 (6) ◽  
pp. 649-661 ◽  
Author(s):  
Camille TRUONG ◽  
Yamama NACIRI ◽  
Philippe CLERC
Keyword(s):  
Principal Component ◽  
Linear Analysis ◽  
Species Differentiation ◽  
Substantial Variation ◽  
Type Specimens ◽  
South West ◽  
Anatomical Characters ◽  
Species Being ◽  
Species Class ◽  
Spore Length

AbstractThis study investigates how anatomical characters can be used to differentiate two morphologically close species, Melanohalea olivacea (L.) O. Blanco et al. and M. septentrionalis (Lynge) O. Blanco et al. Although the two species are morphologically differentiated, mainly based on the position and shape of pseudocyphellae on the lobes, poorly-developed specimens can be difficult to identify based on morphology alone. For example, in Switzerland, both species are at the south-west limit of their distribution range and most specimens are small and not fully developed. In such cases, anatomical characters are particularly useful in separating the two species. Five anatomical characters were studied: spore length and width; hymenium, subhymenium and hypothecium height. A nested ANOVA showed that variation of spore length was 155 times greater between species than between individuals of the same species, itself 5 times higher than within individuals. In a Principal Component Analysis, despite a substantial variation of the anatomical characters within both species, a significant species differentiation appeared distinctly on the first axis (P < 0·001), which accounted for 62·35% of the total variance, and the type specimens nested within each species. Finally, a Discriminant Linear Analysis assigned 100% of the individuals to their species class, the best predictors to discriminate between the two species being subhymenium height and spore length. These characters proved to be powerful in identifying specimens with a poorly-developed morphology and confirmed the presence of M. olivacea in Switzerland.

The interaction of Schistosoma haematobium and S. guineensis in Cameroon

2005 ◽  
Vol 79 (3) ◽  
pp. 193-197 ◽  
Author(s):  
B.L. Webster ◽  
L.A. Tchuem Tchuenté ◽  
J. Jourdane ◽  
V.R. Southgate
Keyword(s):  
Internal Transcribed Spacer ◽  
Schistosoma Haematobium ◽  
Introgressive Hybridization ◽  
Biological Data ◽  
Hybrid Zones ◽  
Hybridization Data ◽  
South West ◽  
Single Stranded Conformational Polymorphism ◽  
Second Internal Transcribed Spacer ◽  
Species Being

AbstractInteractions between schistosomes are complex with some different species being able to mate and hybridize. The epidemiology of schistosomiasis in specific areas of South West Cameroon has evolved remarkably over 30 years as a result of hybridization between Schistosoma guineensis and S. haematobium. Morphological and biological data suggest that S. haematobium replaced S. guineensis in areas of Cameroon through introgressive hybridization. Data are reported on the use of single stranded conformational polymorphism (SSCP) analysis of the nuclear ribosomal second internal transcribed spacer (ITS2) of individual schistosomes from hybrid zones of Cameroon. The data show that since 1990 S. haematobium has completely replaced S. guineensis in Loum, with S. haematobium and the recombinants still present in 2000. This study illustrates the complexities of the dynamics between S. haematobium and S. guineensis in South West Cameroon.

scholarly journals Population structure of five native sheep breeds of Sweden estimated with high density SNP genotypes

BMC Genetics ◽  
2020 ◽  
Vol 21 (1) ◽  
Author(s):  
Christina Marie Rochus ◽  
Elisabeth Jonas ◽  
Anna M. Johansson
Keyword(s):  
Population Structure ◽  
Snp Array ◽  
Principal Component ◽  
Northern Sweden ◽  
The Baltic Sea ◽  
Sheep Breeds ◽  
The North ◽  
South West ◽  
Branch Lengths ◽  
The Baltic

Abstract Background Native Swedish sheep breeds are part of the North European short-tailed sheep group; characterized in part by their genetic uniqueness. Our objective was to study the population structure of native Swedish sheep. Five breeds were genotyped using the 600 K SNP array. Dalapäls and Klövsjö sheep are from the middle of Sweden; Gotland and Gute sheep from Gotland, an island in the Baltic Sea; and Fjällnäs sheep from northern Sweden. We studied population structure by: principal component analysis (PCA), cluster-based analysis of admixture, and an estimated population tree. Results The analyses of the five Swedish breeds revealed that these breeds are five distinct breeds, while Gute and Gotland are more closely related to each other as seen in all analyses. All breeds had long branch lengths in the population tree indicating they’ve been subjected to drift. We repeated our analyses using 39 K SNP and including 50 K SNP genotypes from other European and southwestern Asian breeds from the Sheep HapMap project and 600 K SNP genotypes from a dataset of French sheep. Results arranged breeds into five groups: south-west Asia, south-west Europe, central Europe, north Europe and north European short-tailed sheep. Within this last group, Norwegian and Icelandic breeds, Finn and Romanov sheep, Scottish breeds, and Gute and Gotland sheep were more closely related while the remaining Swedish breeds and Ouessant sheep were distinct from all breeds and had longer branches in the population tree. Conclusions We showed population structure of five Swedish breeds and their structure within European and southwestern Asian breeds. Swedish breeds are unique, distinct breeds that have been subjected to drift but group with other north European short-tailed sheep.

Leaf anatomy of Carex humilis does not correlate with orographic, geological and bioclimatic habitat conditions in C&SE Europe

Biologia ◽  
2014 ◽  
Vol 69 (3) ◽  
Author(s):  
Ksenija Jakovljević ◽  
Jasmina Šinžar-Sekulić ◽  
Snežana Vukojičić ◽  
Nevena Kuzmanović ◽  
Dmitar Lakušić
Keyword(s):  
Principal Component ◽  
Canonical Discriminant Analysis ◽  
Habitat Characteristics ◽  
Morphometric Study ◽  
Geological Condition ◽  
Habitat Conditions ◽  
Adaptive Responses ◽  
Geological Conditions ◽  
Anatomical Characters ◽  
Climatic Characteristics

AbstractThis paper presents the results of a multivariate morphometric study of leaf anatomical characters in different, geographically very distant populations of taxon Carex humilis from Hungary, Romania, Serbia, Bosnia & Herzegovina, Montenegro and Albania with the aim to reveal the trends of population differentiation. Analyses were performed on the cross-section of 173 leaves collected from 12 populations. In order to establish the overall morphological variation and relationships between individuals from all populations, principal component analyses (PCA) and canonical discriminant analysis (CDA) have been done. The UPGMA clustering analyses based on leaf anatomical characters and habitat climatic characteristics were carried out to explore whether the observed anatomical differences are a result of adaptive responses. Regression analysis (linear regression) was performed to identify the level of correlation between leaf anatomical characters and basic orographic, geological, and bioclimatic habitat characteristics. Quite unexpectedly, most of observed groups are formed of geographically very distant populations which are living in extremely different climatic and geological conditions, indicating that general anatomical differentiation in Carex humilis in C&SE Europe cannot be explained by the environmental impacts, and basically do not represent an adaptive response to different climatic or geological condition.

Comparative Analysis of Development Level of New-Type Urbanization & Traditional Urbanization in Shandong Province

2015 ◽  
Vol 744-746 ◽  
pp. 2258-2262
Author(s):  
Bao Yan Shan ◽  
Li’e Wang
Keyword(s):  
Principal Component ◽  
Shandong Province ◽  
Shandong Peninsula ◽  
Urbanization Level ◽  
North West ◽  
The North ◽  
Development Level ◽  
South West ◽  
New Type ◽  
The Difference

In order to analyze the difference of the level of new-type and traditional urbanization of Shandong province, 20 indexes were selected involving economic, society and environment, etc, and principal component analysis was applied to calculate the score of the new-type urbanization levels of the 108 cities in Shandong in 2008 and 2013, and GIS was applied to analyze the spatial distribution of the levels. The results show that the cities whose new-type urbanization level is higher than that of traditional urbanization are located at the east of Shandong peninsula urban agglomeration, and the cities whose new-type urbanization level is lower than that of traditional urbanization are located at the north-west and south-west of the province in both 2008 and 2012.

scholarly journals VI.—On the Microzoa Found in Some Jurassic Rocks of England

1886 ◽  
Vol 3 (6) ◽  
pp. 271-274 ◽  
Author(s):  
T. Rupert Jones ◽  
C. D. Shebborn
Keyword(s):  
The South ◽  
Number Of Species ◽  
South West ◽  
Jurassic Rocks ◽  
Being There ◽  
Species Being ◽  
Geological Magazine

In the Geological Magazine, Dec. II. Vol. II. 1875, p. 308, is a list of some English Jurassic Foraminifera, a large number of species being there noted as occurring in these rocks. We have lately received, by the friendly courtesy of the Rev. H. H. Winwood, F.G.S., and Horace B. Woodward, Esq., F.G.S., thirteen specimens of the Jurassic rocks from the south-west of England. One of these has yielded a most important series of Ostracoda. Whilst preparing a special monograph, we hasten to offer some preliminary notes on these interesting Jurassic Microzoa, at present merely noting the genera, in descending order of strata, and deferring the specific nomenclature for a subsequent opportunity.

scholarly journals Undercover speciation of wentletraps (Caenogastropoda: Epitoniidae) in the Southwestern Atlantic

Zootaxa ◽  
2017 ◽  
Vol 4286 (1) ◽  
pp. 41
Author(s):  
DIEGO G. ZELAYA ◽  
MARINA GÜLLER
Keyword(s):  
New Species ◽  
Atlantic Coast ◽  
Intraspecific Variability ◽  
Shell Morphology ◽  
Southwestern Atlantic ◽  
Number Of Species ◽  
Anatomical Characters ◽  
Three New Species ◽  
First Time ◽  
Species Being

Despite being one of the most speciose families, Epitoniidae still remains at present as one of the least understood gastropod families worldwide. This is a consequence of most of the species being only known from shell morphology, added to the wide intraspecific variability of this character and the fact that shell morphology has proven to have frequent examples of parallelisms and convergences among different (unrelated) species. Knowledge of other morphological and anatomical characters in this group is still in its first steps, and such information is currently available for a limited number of species, thus being difficult (when not impossible) to evaluate its taxonomic value. The aim of this study is to re-evaluate the diversity of Epitoniidae occurring in the Atlantic coast of Patagonia. As part of this study, the validity of only four of the six species described / reported from this area could be confirmed: Epitonium georgettinum, E. striatellum, E. fabrizioi and “Cirsotrema” magellanicum. In addition, three new species were recognized and are described herein: Epitonium evanidstriatum, “Cirsotrema” ctenodentatum and “Cirsotrema” strebeli. Information on the shell (including the protoconch), operculum, radula and jaw for these species is here provided, in most cases for the first time. A neotype for Scalaria magellanica is here designated. Furthermore, “Cirsotrema” georgeanum is here proposed as a replacement name for Scalaria fenestrata Strebel, 1908 (not Meneghini in de Stefani, 1875, nor Scalaria fenestrata Wöhrmann, 1889); and that taxon is regarded as a full species, instead of as a synonym of “Cirsotrema” magellanicum, as suggested in some previous publications. This study reveals that the usage of isolated (either morphological or anatomical) characters is usually insufficient for identifying some of the species from Patagonia; however, if these characters are combined, all species may be clearly recognized. 

scholarly journals Anatomía comparada del leño de Maytenus en el Noroeste de Argentina (Sudamérica)

2014 ◽  
Vol 20 (2) ◽  
pp. 95-110 ◽  
Author(s):  
Ana María Giménez ◽  
Juana Graciela Moglia ◽  
M. E. Figueroa ◽  
J. A. Díaz-Zírpolo ◽  
Federico Calatayu
Keyword(s):  
Principal Component Analysis ◽  
Wood Anatomy ◽  
Principal Component ◽  
Vessel Diameter ◽  
Diagnostic Features ◽  
Northwestern Argentina ◽  
Diameter Fibre ◽  
Microscopic Features ◽  
Anatomical Characters ◽  
Comparative Wood Anatomy

Comparative wood anatomy of Maytenus in Northwestern Argentina (South America)This paper is a comparative wood anatomy study of four species of the genus Maytenus living in Northwest Argentina: Maytenus vitisidaea, M. viscifolia, M. spinosa and M. cuezzoi. The specimens were collected in Santiago del Estero and Salta, Argentina and wood samples are safeguarded in the collection of the LAM (Laboratory of Wood Anatomy), Faculty of Forestry of Santiago del Estero University (UNSE), Argentina. The terminology used followed the IAWA List of Microscopic Features for Hardwood Identification. The diagnostic features of wood anatomical characters were evaluated by employing statistical methods such as Cluster Analysis (CA) and Principal Component Analysis (PCA). PCA showed vessel diameter, fibre wall, and ray width to be significant variables. CA showed M. cuezzoi and M. viscifolia to have the highest affinity.Anatomía comparada del leño de Maytenus en el Noroeste de Argentina (Sudamérica)El presente trabajo es un estudio de anatomía comparada de madera de cuatro especies del género Maytenus del Noroeste Argentino:Maytenus vitis-idaea, M. viscifolia, M. spinosa y M. cuezzoi. Las muestras fueron recolectadas en Santiago del Estero y Salta, Argentinay se salvaguardan en la colección del LAM (Laboratorio de Anatomía de Madera), Facultad de Ciencias Forestales de la Universidad deSantiago del Estero (UNSE), Argentina. Se empleó la terminología de IAWA (Lista de caracteres anatómicos del xilema de angiospermas).Los caracteres anatómicos de madera fueron evaluados mediante métodos estadísticos tales como análisis de conglomerados (AC) y elAnálisis de Componentes Principales (PCA). El PCA mostró como variables significativas el diámetro de vasos, el espesor de pared de lasfibras y el ancho de radios. El CA mostró que M. cuezzoi y M. viscifolia tienen alta afinidad específica.

scholarly journals DIAGNOSTIC AND DESCRIPTION OF ASIAN PANGASIID CATFISH GENUS Helicophagus FROM SOUTHEAST ASIA

2019 ◽  
Vol 25 (2) ◽  
pp. 123
Author(s):  
Rudhy Gustiano ◽  
Muhammad Hunaina Fariduddin Ath-thar ◽  
Vitas Atmadi Prakoso ◽  
Deni Radona ◽  
Irin Iriana Kusmini
Keyword(s):  
Principal Component Analysis ◽  
Southeast Asia ◽  
Principal Component ◽  
Component Analysis ◽  
Type Specimens ◽  
Body Conformation ◽  
Eye Diameter ◽  
Distribution And Ecology

Pangasiid catfishes is an economic important catfish family for fishery. Nowadays, three species, Pangasius hypophtahlmus, P. boucorti, and P. djambal, are used in aquaculture. Among the genera in Pangasiidae, Helicophagus was less studied. Although this genus was less preferred than other popular species in Pangasiidae, it still has high commercial price. The present study was conducted to clarify the differences of the exist species in the genus Helicophagus based on biometric analyses. Twenty six specimens, collected from represent rivers in Southeast Asia, used for the material examined. Several type specimens deposited in museums were also added in the analyses. Thirty five characters were designed for measurement on the unique body conformation. Principal component analysis (PCA) was applied to distinguish different species and found strong characters for key identification and description. The results presented the data and information on the diagnosis, description, distribution, and ecology of each species. Key identification of each species are given. The three species (Helicophagus typus, H. waandersii, and H. leptorhynchus) enabled to show their differences based on eye diameter and vomerine toothplate length.

scholarly journals IDENTIFIKASI TIGA KELOMPOK IKAN BELIDA (Chitala lopis) DI SUNGAI TULANG BAWANG, KAMPAR, DAN KAPUAS DENGAN PENDEKATAN BIOMETRIK

2017 ◽  
Vol 13 (2) ◽  
pp. 87
Author(s):  
Mas Tri Djoko Sunarno
Keyword(s):  
Principal Component Analysis ◽  
Sampling Site ◽  
Principal Component ◽  
Component Analysis ◽  
Sampling Station ◽  
Type Specimens ◽  
Purposive Sampling ◽  
Starting Point ◽  
Mouth Width ◽  
Peduncle Length

Aktivitas penangkapan lebih (over fishing), penggunaan alat tangkap yang tidak ramah lingkungan, dan perubahan kondisi lingkungan perairan menyebabkan kelestarian ikan belida (Chitala lopis) menjadi terancam. Untuk itu, diperlukan upaya konservasi yang tepat untuk melestarikan ikan ini. Tahap awal adalah melalui penelitian morfologi. Tujuan penelitian adalah mengidentifikasi keragaman jenis ikan belida di Sungai Tulang Bawang (Lampung), Kampar (Riau), dan Kapuas (Kalimantan Barat) melalui variasi bentuk tubuh dan karakter morfologi pembeda. Penentuan lokasi pengambilan contoh dilakukan secara purposive sampling. Untuk setiap spesies pengambilan contoh per lokasi berkisar antara 10 sampai dengan 30 spesimen. Contoh ditandai (tagging) dituliskan kode spesimen dan lokasi kemudian diawetkan dengan direndam larutan alkohol 75%. Pengukuran spesimen dengan digital kaliper di sisi tubuh sebelah kiri, pada 28 karakter morfologi. Data yang diperoleh distandarisasi, disajikan dalam % SL dan % HL yang merupakan subyek principal component analysis menggunakan Statistik 6.0. Tahap ke-2, menggunakan analysis diskriminan untuk mengisolasi ke tipe spesimen tadi menjadi kelompok yang terpisah, melihat karakter morfologi dominan (factor score coefficient) akhirnya hanya 1 karakter yang paling dominan. Terdapat 3 kelompok ikan belida yang memperlihatkan penampilan morfologi yang berbeda, dari ke-3 lokasi yang diamati. Pembeda ke-3 kelompok ikan belida di 3 sungai tersebut adalah peduncle length (tinggi punguk) (% HL) dan mouth width (lebar mulut) (% SL). Over fishing activities, implementation of unfriendly environmental gears and altered aquatic environment condition have endangered the feather fish (Chitala lopis). Therefore appropriate conservation efforts will be needed and research on morphology variance can be the starting point. The objective of research is to indentify the diversity of feather fish in Tulang Bawang (Lampung), Kampar (Riau), and Kapuas (Kalimantan Barat) rivers through body shape variations and it’s main morphology characters. Sampling station were chosen based on purposive sampling. Whatever possible, the number of samples range between 10 to 30 in every station sampling. Samples were tagged with specimen code and location, and then preserve using alcohol 75%. Measurements were made manually using dial calipers correct to tenth milimetre. Measurements were made on the left side of body, 28 point to point measurements. These characters were standardized, perform in % SL and % HL subject to principal component analysis using Statistica 6.0. Futher analysis using discriminant analysis to isolate 3 type specimens, find out the dominant characters, and finally see the most dominance characters. There are 3 groups of feather fish’s that performed different morphology characters from the sampling site, where as peduncle length (% HL) and mouth width (% SL) were the dominance characters.

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