scholarly journals Linear and geometric morphometrics as tools to resolve species circumscription in the Pseudolaelia vellozicola complex (Orchidaceae, Laeliinae)

2019 ◽  
Vol 152 (1) ◽  
pp. 53-67 ◽  
Author(s):  
Luiz Menini Neto ◽  
Cássio Van den Berg ◽  
Rafaela Campostrini Forzza
Keyword(s):  
Natural Populations ◽  
Distinct Species ◽  
Multivariate Methods ◽  
Brazilian Atlantic Forest ◽  
Morphometric Data ◽  
Elliptic Fourier Analysis ◽  
Linear Measurements ◽  
Species Circumscription ◽  
Eastern Brazil ◽  
Sufficient Magnitude

Background and aims – Pseudolaelia is a genus endemic to eastern Brazil, with 12 accepted species predominantly distributed across granitic inselbergs of the Brazilian Atlantic Forest. The aim of the present study was to distinguish between the very similar taxa P. aguadocensis, P. oliveirana, P. regentii and P. vellozicola, using morphometric data acquired as linear measurements and outlines capture with Elliptic Fourier Analysis (EFA) of the floral parts. Material and methods – We sampled 208 specimens from 11 natural populations of the above taxa. We measured 20 floral variables and for the EFA, and we extracted 24 shape variables from the Fourier coefficient matrices, which describe the outlines of the floral parts. In both cases the data were analyzed with multivariate methods (both ordination and clustering). Key results – We could not find morphological discontinuities with sufficient magnitude to consider P. aguadocensis, P. oliveirana and P. regentii as distinct species from P. vellozicola. Conclusions – We propose that P. vellozicola should be considered a polymorphic and widely distributed species, generally supported by both methods.

PATTERNS AND PROCESSES IN MORPHOSPACE: GEOMETRIC MORPHOMETRICS OF THREE-DIMENSIONAL OBJECTS

2016 ◽  
Vol 22 ◽  
pp. 71-99 ◽  
Author(s):  
P. David Polly ◽  
Gary J. Motz
Keyword(s):  
Geometric Morphometrics ◽  
Three Dimensional ◽  
Shape Space ◽  
Multivariate Methods ◽  
Morphometric Data ◽  
Three Dimensional Objects ◽  
Mathematical Properties ◽  
Patterns And Processes ◽  
The Relationship ◽  
Shell Coiling

AbstractFocusing on geometric morphometrics (GMM), we review methods for acquiring morphometric data from 3-D objects (including fossils), algorithms for producing shape variables and morphospaces, the mathematical properties of shape space, especially how they relate to morphogenetic and evolutionary factors, and issues posed by working with fossil objects. We use the Raupian shell-coiling equations to illustrate the complexity of the relationship between such factors and GMM morphospaces. The complexity of these issues re-emphasize what are arguably the two most important recommendations for GMM studies: 1) always use multivariate methods and all of the morphospace axes in an analysis; and 2) always anticipate the possibility that the factors of interest can have complex, nonlinear relationships with shape.

scholarly journals Bite force, cranial morphometrics and size in the fishing bat Myotis vivesi (Chiroptera: Vespertilionidae).

2018 ◽  
Vol 66 (4) ◽  
Author(s):  
Sandra Milena Ospina
Keyword(s):  
Significant Contribution ◽  
Morphological Characters ◽  
Bite Force ◽  
Multivariate Methods ◽  
Morphometric Data ◽  
Insectivorous Bats ◽  
Temporal Muscle ◽  
Skull Size ◽  
Cranial Measurements

Fish-eating in bats evolved independently in Myotis vivesi (Vespertillionidae ) and Noctilio leporinus (Noctilionidae). We compared cranial morphological characters and bite force   between these species to test the existence of evolutionary parallelism in piscivory. We collected cranial distances of M. vivesi, two related insectivorous bats (M. velifer and M. keaysi), two facultatively piscivorous bats (M. daubentonii and M. capaccinii), and N. leporinus to test for differences among the six species, morphometric data was analyzed applying multivariate methods. We also measured bite force in M. vivesi and evaluated if this value was well predicted by its cranial size. Both piscivorous species were morphologically different from the facultatively piscivorous and insectivorous species, and skull size had a significant contribution to this difference. However, we did not find morphological and functional similarities that could be interpreted as parallelisms between M. vivesi and N. leporinus. These two piscivorous species differed significantly in cranial measurements and in bite force. Bite force measured for M. vivesi was well predicted by skull size. Piscivory in M. vivesi might be associated to the existence of a vertically displaced temporal muscle and an increase in gape angle that allows a moderate bite force to process food.

Disentangling Leaf Morphology in Daustinia montana (Convolvulaceae)

2020 ◽  
Vol 45 (4) ◽  
pp. 921-930
Author(s):  
Juliana Alencar ◽  
André Luiz Borba do Nascimento ◽  
Paulo Duarte-Neto ◽  
Maria Teresa Buril
Keyword(s):  
Clustering Analysis ◽  
Leaf Morphology ◽  
Morphological Characteristics ◽  
Climatic Variables ◽  
Shape Descriptors ◽  
Elliptic Fourier Analysis ◽  
Linear Measurements ◽  
Elliptic Fourier Descriptors ◽  
Main Components ◽  
Large Groups

Abstract—Daustinia montana (Convolvulaceae) is the only species of the genus, and is notable for its wide leaf variability. To understand whether this plasticity is correlated with the distribution of the species, linear morphometric and leaf contour analyses were performed. Specimens from herbaria were photographed, and pre-established linear measurements were made. A multivariate analysis was then performed to test the strength of associations among morphological characteristics, climatic variables, and distribution of the species. Elliptic Fourier analysis based on 20 harmonics was used to generate shape descriptors, resulting in nine main components. With elliptic Fourier descriptors, a grouping tree was created that suggests the existence of six morphotypes in D. montana. Moreover, clustering analysis revealed two large groups distinguished mainly by leaf width. The present findings indicate that the morphotypes are strongly related to latitude and that other characteristics such as the type of indumentum are related to climatic variables.

The restablishment of Dyckia oligantha and D. nana (Bromeliaceae, Pitcairnioideae), belonging to the D. macedoi complex

Phytotaxa ◽  
2017 ◽  
Vol 306 (1) ◽  
pp. 49 ◽  
Author(s):  
ELIDIO ARMANDO EXPOSTO GUARÇONI ◽  
ARISTÉIA ALVES DE AZEVEDO ◽  
ANDREA FERREIRA DA COSTA
Keyword(s):  
Multivariate Analysis ◽  
Natural Populations ◽  
Distinct Species ◽  
Reproductive Characters

The authors reestablish Dyckia oligantha and D. nana, considered synonymous of D. saxatilis and D. macedoi, respectively, on the basis of newly collected specimens from the type localities. Multivariate analysis of vegetative and reproductive characters on natural populations of the species of the D. macedoi complex were performed, allowing the recognition of D. macedoi, D. nana and D. oligantha as distinct species.

A new stingless bee species of the genus Scaura (Hymenoptera, Apidae) from the Brazilian Atlantic forest, with notes on S. latitarsis (Friese)

Zootaxa ◽  
2004 ◽  
Vol 544 (1) ◽  
pp. 1 ◽  
Author(s):  
GABRIEL A.R. MELO ◽  
MARCO ANTÔNIO COSTA
Keyword(s):  
New Species ◽  
Body Size ◽  
Atlantic Forest ◽  
Posterior Margin ◽  
Stingless Bee ◽  
Brazilian Atlantic Forest ◽  
Type Series ◽  
Eastern Brazil ◽  
A New Species ◽  
Original Type

A new species, Scaura atlantica Melo, is described from eastern Brazil. It belongs to the latitarsis group and can be distinguished from workers of S. latitarsis especially by its larger body size, darker color, smoother upper frons, and by the contour of the posterior margin of the hind basitarsus; from workers of S. argyrea, n. stat., it differs by possessing a frons with shorter simple setae whose sockets are less protuberant, shorter simple setae on the mesoscutum and by the shape of the hind basitarsus. Considering that the original type series of Trigona latitarsis Friese, 1900, is probably composed of more than one species, a worker syntype from Brazil (Jundia , S o Paulo) is here designated lectotype in order to stabilize the taxonomy of the group.

scholarly journals Nuclear Gene Genealogies Reveal Historical, Demographic and Selective Factors Associated With Speciation in Field Crickets

Genetics ◽  
2003 ◽  
Vol 163 (4) ◽  
pp. 1389-1401 ◽  
Author(s):  
Richard E Broughton ◽  
Richard G Harrison
Keyword(s):  
Population Size ◽  
Effective Population Size ◽  
Natural Populations ◽  
Nuclear Gene ◽  
Distinct Species ◽  
Effective Population ◽  
Ancestral Polymorphisms ◽  
History Of ◽  
Selective Forces ◽  
Shared Polymorphism

Abstract Population genetics theory predicts that genetic drift should eliminate shared polymorphism, leading to monophyly or exclusivity of populations, when the elapsed time between lineage-splitting events is large relative to effective population size. We examined patterns of nucleotide variation in introns at four nuclear loci to relate processes affecting the history of genes to patterns of divergence among natural populations and species. Ancestral polymorphisms were shared among three recognized species, Gryllus firmus, G. pennsylvanicus, and G. ovisopis, and genealogical patterns suggest that successive speciation events occurred recently and rapidly relative to effective population size. High levels of shared polymorphism among these morphologically, behaviorally, and ecologically distinct species indicate that only a small fraction of the genome needs to become differentiated for speciation to occur. Among the four nuclear gene loci there was a 10-fold range in nucleotide diversity, and patterns of polymorphism and divergence suggest that natural selection has acted to maintain or eliminate variation at some loci. While nuclear gene genealogies may have limited applications in phylogeography or other approaches dependent on population monophyly, they provide important insights into the historical, demographic, and selective forces that shape speciation.

scholarly journals Using morphometrics to reappraise old collections: The study case of the Congo Basin Middle Stone Age bifacial industry

2020 ◽  
Vol 7 (1) ◽  
Author(s):  
Isis Mesfin ◽  
Alice Leplongeon ◽  
David Pleurdeau ◽  
Antony Borel
Keyword(s):  
Homo Sapiens ◽  
Central Africa ◽  
Middle Stone Age ◽  
Congo Basin ◽  
Stone Age ◽  
Elliptic Fourier Analysis ◽  
Linear Measurements ◽  
Behavioural Patterns ◽  
Study Case ◽  
Shape Ratio

Despite its strategic location within the continent, Central Africa is rarely integrated into the reconstruction of population dynamics during the Middle Stone Age (MSA) of Africa, especially in terms of the emergence, diffusion and behavioural patterns of Homo sapiens. However, hundreds of sites have been discovered in Central Africa during the 20th century and attributed to the Lupemban, one of the main MSA technological complexes of the region. This complex is mainly characterised by typological criteria based on the numerous bifacial pieces found in the Congo Basin and interpreted as an adaption to the rainforest environment. Most of these Lupemban assemblages have not been studied for decades and thus it is particularly difficult to assess their diversity. This paper presents a detailed combined morphometrical approach (linear measurements and indices, Log Shape Ratio, Elliptic Fourier Analysis) to take a fresh and rigorous look at the Lupemban bifacial tools. We discuss the comparison of different morphometrical approaches to deal with “old” collections for which contexts, particularly chronological ones, are partially missing. We present the results of this approach on three assemblages of bifacial pieces gathered in the 1930s and late 1960s. We quantify their variability and discuss not only their homogeneity but also the variation of a Lupemban hallmark, namely the “Lupemban point”.

scholarly journals Comparative transcriptomics of seven Impatiens species

2021 ◽  
Author(s):  
Mária Šurinová ◽  
Štepán Stočes ◽  
Tomáš Dostálek ◽  
Andrea Jarošová ◽  
Zuzana Münzbergová
Keyword(s):  
De Novo ◽  
Protein Structures ◽  
Natural Populations ◽  
Gene Families ◽  
Single Species ◽  
Distinct Species ◽  
Species Group ◽  
Specific Gene ◽  
Flowering Regulation ◽  
Species Specific

AbstractImpatiens is a genus containing more than 1000 species. Thanks to its size, it is a unique system for studying species diversification in natural populations. This study focused on the characterization of novel transcriptomes from seven Impatiens species originating from Nepal. Leave transcriptome of Impatines balsamina L., I. racemosa DC., I. bicornuta Wall, I. falcifer Hook, I. devendrae Pusalkar, I. scullyi Hook and I. scabrida DC were sequenced and compared. Reads were de novo assembled and aligned to 92 035-226 081 contigs. We identified 14 728 orthology groups shared among all the species and 3 020 which were unique to a single species. In single species, 2536-3009 orthology groups were under selection from which 767 were common for all species. Six of the seven investigated species shared 77% of gene families with I. bicornuta being the most distinct species. Specific gene families involved in response to different environmental stimuli were closely described. Impatiens bicornuta selection profile shared selection on zing finger protein structures and flowering regulation and stress response proteins with the other investigated species. Overall, the study showed substantial similarity in patterns of selections on transcribed genes across the species suggesting similar evolutionary pressures. This suggests that the species group may have evolved via adaptive radiation.

scholarly journals Taxonomic value of foliar characters in Dahlstedtia Malme: Leguminosae, Papilionoideae, Millettieae

2006 ◽  
Vol 20 (2) ◽  
pp. 395-403 ◽  
Author(s):  
Simone de Pádua Teixeira ◽  
Antonio Carlos Gabrielli
Keyword(s):  
Natural Populations ◽  
Cambial Activity ◽  
Leaf Primordium ◽  
Cultivated Plants ◽  
Brazilian Atlantic Forest ◽  
Secretory Cavities ◽  
Anatomical Characters ◽  
Surface Assessment ◽  
Important Character ◽  
Scanning Electron

Dahlstedtia Malme (Leguminosae) is a neotropical genus, native to the Brazilian Atlantic Forest, and comprises two species, D. pinnata (Benth.) Malme and D. pentaphylla (Taub.) Burk., although it has been considered a monotypic genus by some authors. Leaf anatomy was compared to verify the presence of anatomical characters to help delimit species. Foliar primordium, leaflet, petiolule, petiole and pulvinus were collected from cultivated plants (Campinas, SP, Brazil) and from natural populations (Picinguaba, Ubatuba and Caraguatatuba, SP, Brazil - D. pinnata; Antonina, PR, Brazil - D. pentaphylla). Studies on leaflet surface assessment (Scanning Electron Microscopy), as well as histology and venation analyses were carried out of dehydrated, fresh and fixed material from two species. Leaflet material was macerated for stomatal counts. Histological sections, obtained by free-hand cut or microtome, were stained with Toluidine Blue, Safranin/Alcian Blue, Ferric Chloride, Acid Phloroglucin. Secretory cavities are present in the lamina, petiolule, petiole, pulvinus and leaf primordium in D. pentaphylla, but not in D. pinnata, and can be considered an important character for species diagnosis. Other leaf characters were uninformative in delimiting Dahlstedtia species. There is cambial activity in the petiolule, petiole and pulvinus. This study, associated with other available data, supports the recognition of two species in Dahlstedtia.

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