scholarly journals Paranephelius (Asteraceae: Liabeae): A case study in high-elevation hybridization and taxonomic insights

2021 ◽  
Vol 15 (2) ◽  
pp. 351-376
Author(s):  
Michael O. Dillon ◽  
Mario Enrique Zapata Cruz ◽  
Victor Quipuscoa Silvestre
Keyword(s):  
Sequence Data ◽  
High Elevation ◽  
Species Boundaries ◽  
Geographic Scale ◽  
Northern Peru ◽  
Prior Investigation ◽  
Taxonomic Confusion ◽  
Species Descriptions ◽  
Putative Hybrids

Paranephelius Poepp. (Liabeae: Asteraceae) is a genus, here comprised of three species confined to high-elevation Andean habitats from 3°–25°S latitude from northern Peru to northern Argentina. In a prior investigation, sequence data was analyzed from samples throughout the range of the genus to evaluate the morphological variation used in delineating species. This detailed sampling allowed for molecular studies at a fine geographic scale. Within Paranephelius, genetic divergence is low, and not adequate to fully resolve phylogenetic relationships at the species level. Two genetically and morphologically recognizable genomes were reveled in northern Peru; these correspond to P. ovatus Wedd. and P. uniflorus Poepp., respectively. Several accessions possess sequences representing putative hybrids between these two species. These putative hybrids have caused taxonomic confusion in establishing species boundaries in Paranephelius. The molecular analysis suggested that P. asperifolius (Muschl.) H. Rob. & Brettell, distributed in Bolivia and northwestern Argentina, is related to P. ovatus, while it most closely resembles P. uniflorus. Species that have changed status include, P. ferreyrae H. Rob., here within the parameters of P. uniflorus; and P. jelskii (Hieron.) H. Rob. & Brettell, P. bullatus A. Gray ex Wedd., and P. wurdackii H. Rob. are here within parameters of P. ovatus. This study is not intended to be a monograph, but does includes a key to species, descriptions, illustrations, and citation of specimens examined.

scholarly journals Quantifying morphological variation in the Castilleja pilosa species complex (Orobanchaceae)

PeerJ ◽  
2019 ◽  
Vol 7 ◽  
pp. e7090
Author(s):  
Sarah J. Jacobs ◽  
Sarah Herzog ◽  
David C. Tank
Keyword(s):  
Morphological Variation ◽  
Species Complex ◽  
Species Boundaries ◽  
Similar Species ◽  
Type Specimens ◽  
Diagnostic Features ◽  
Species Complexes ◽  
Taxonomic Confusion ◽  
Species Descriptions ◽  
The Impact

Robustly delimited species are of paramount importance, the identification of which relies on our ability to discern boundaries between one species and the next. This is not difficult to do when species are very distinct from one another. However, in recently evolved lineages where putative species may have relatively few diagnostic features (e.g., species complexes composed of very similar species, the boundaries between which are often unclear), defining species boundaries can be more challenging. Hence, the field of species delimitation has widely advocated the use of multiple lines of evidence to delimit species, particularly in species complexes. Excessive taxonomic confusion, often the result of species descriptions that shift through time (e.g., during revisionary work and regional treatments), can further complicate the search for diagnostic features in species complexes. Here, as a first step in robustly delimiting species boundaries, we quantify and describe morphological variation in the Castilleja pilosa species complex. We first infer the morphospace of the species complex and use fuzzy-clustering techniques to explore the morphological variation in the system. Next, we hypothesize the position of type specimens within that morphospace. In so doing, we aim to visualize the impact that regional treatments have had on the conceptualization of taxa through time. We find that there is limited morphological variation among members of this complex, and we determine that the morphological concept of these species have shifted through time and are no longer accurately represented by species descriptions.

Revision of Banded Knifefishes of the Gymnotus carapo and G. tigre clades (Gymnotidae Gymnotiformes) from the Southern Neotropics

Zootaxa ◽  
2018 ◽  
Vol 4379 (1) ◽  
pp. 47 ◽  
Author(s):  
JACK M. CRAIG ◽  
LUIZ R. MALABARBA ◽  
WILLIAM G. R. CRAMPTON ◽  
JAMES S. ALBERT
Keyword(s):  
Lateral Line ◽  
Electric Organ ◽  
Valid Species ◽  
Species Boundaries ◽  
Multivariate Statistical ◽  
Widespread Species ◽  
Statistical Framework ◽  
Fin Ray ◽  
Taxonomic Confusion ◽  
Electric Organ Discharges

Banded Knifefishes (Gymnotus, Gymnotidae) comprise the most species-rich, ecologically tolerant (eurytopic), and geographically widespread genus of Neotropical electric fishes (Gymnotiformes), with 40 valid species occupying most habitats and regions throughout the humid Neotropics. Despite substantial alpha-taxonomic work in recent years, parts of the genus remain characterized by taxonomic confusion. Here we describe and delimit species of the G. carapo and G. tigre clades from the southern Neotropics, using body proportions (caliper-based morphometrics), fin-ray, scale and laterosensory-pore counts (meristics), quantitative shape differences (geometric morphometrics), osteology, color patterns and electric organ discharges. We report these data from 174 Gymnotus specimens collected from 100 localities throughout the southern Neotropics, and delimit species boundaries in a multivariate statistical framework. We find six species of the G. carapo clade (G. carapo australis, G. cuia n. sp., G. chimarrao, G. omarorum, G. pantanal, and G. sylvius), and two species of the G. tigre clade (G. inaequilabiatus and G. paraguensis) in the southern Neotropics. The new species G. cuia is readily distinguished from the morphologically similar and broadly sympatric G. c. australis by a shorter head and deeper head and body, and from the morphologically similar and sympatric G. omarorum by fewer lateral-line ventral rami and fewer pored lateral-line scales anterior to the first ventral ramus. We also review the geographic distributions of all eight species of the G. carapo and G. tigre clades in the southern Neotropics, showing that G. cuia is the most widespread species in the region. These results affirm the importance of understanding the structure of variation within and between species, both geographic and ontogenetic, in delimiting species boundaries. 

scholarly journals Introducing mothur: Open-Source, Platform-Independent, Community-Supported Software for Describing and Comparing Microbial Communities

2009 ◽  
Vol 75 (23) ◽  
pp. 7537-7541 ◽  
Author(s):  
Patrick D. Schloss ◽  
Sarah L. Westcott ◽  
Thomas Ryabin ◽  
Justine R. Hall ◽  
Martin Hartmann ◽  
...  
Keyword(s):  
16S Rrna ◽  
Software Package ◽  
Sequence Data ◽  
Rrna Gene ◽  
Sequencing Data ◽  
Laptop Computer ◽  
Operational Taxonomic Units ◽  
Β Diversity ◽  
Single Piece

ABSTRACT mothur aims to be a comprehensive software package that allows users to use a single piece of software to analyze community sequence data. It builds upon previous tools to provide a flexible and powerful software package for analyzing sequencing data. As a case study, we used mothur to trim, screen, and align sequences; calculate distances; assign sequences to operational taxonomic units; and describe the α and β diversity of eight marine samples previously characterized by pyrosequencing of 16S rRNA gene fragments. This analysis of more than 222,000 sequences was completed in less than 2 h with a laptop computer.

scholarly journals Mismatch induced speciation in Salmonella : model and data

2006 ◽  
Vol 361 (1475) ◽  
pp. 2045-2053 ◽  
Author(s):  
Daniel Falush ◽  
Mia Torpdahl ◽  
Xavier Didelot ◽  
Donald F Conrad ◽  
Daniel J Wilson ◽  
...  
Keyword(s):  
New Species ◽  
Natural Selection ◽  
Dna Sequence ◽  
Computer Simulations ◽  
De Novo ◽  
Sequence Data ◽  
Biological Species ◽  
Species Boundaries ◽  
Population Subdivision ◽  
Geographical Population

In bacteria, DNA sequence mismatches act as a barrier to recombination between distantly related organisms and can potentially promote the cohesion of species. We have performed computer simulations which show that the homology dependence of recombination can cause de novo speciation in a neutrally evolving population once a critical population size has been exceeded. Our model can explain the patterns of divergence and genetic exchange observed in the genus Salmonella , without invoking either natural selection or geographical population subdivision. If this model was validated, based on extensive sequence data, it would imply that the named subspecies of Salmonella enterica correspond to good biological species, making species boundaries objective. However, multilocus sequence typing data, analysed using several conventional tools, provide a misleading impression of relationships within S. enterica subspecies enterica and do not provide the resolution to establish whether new species are presently being formed.

scholarly journals Farmer Preference to High Elevation Rice Technological Packages for Accelerating Technological Dissemination (A case Study in Humbang Hasundutan Regency)

Agro Ekonomi ◽  
2021 ◽  
Vol 32 (2) ◽  
Author(s):  
Setia Sari Girsang ◽  
Agung B Santosa ◽  
Tommy Purba ◽  
Deddy R Siagian ◽  
Khadijah E Ramija
Keyword(s):  
Low Cost ◽  
High Elevation ◽  
Primary Data ◽  
Survey Method ◽  
User Friendliness ◽  
Level Of Satisfaction ◽  
High Level ◽  
Level Of Importance

Accelerating the introduction of a new technological package is needed to increase the productivity of high elevation puddled rice in Humbang Hasundutan. The objectives of the study are to find out the perception of the existence of technological packages and farmers' preference for a new technological package. The study used a survey method with primary data gathered using questionnaires. The criteria of locations and respondents were used to obtain relevant respondents and data concerning their knowledge of high elevation puddled rice cultivation.  The collected data were processed by using Importance Performance Analysis in order to find out the level of Importance and Satisfaction of the indicators and the valued aspects in the technological package components. The results of the study showed that the socio-economic aspects had to be heeded in organizing the technological package. Indicators having a high level of importance and a low level of satisfaction consisted of production cost, quality of seeds, farmer groups empowerment, technology information institution, capital cost, agricultural tools and machines, pest control, sales price, irrigation canals, and farm roads. On the other hand, introducing new superior seeds, productivity attribute and planting age were important indicators for local farmers as to improve the quality of existing seeds. Farmers group expected that the technological package had a high level of productivity, better access to input, low cost, and good user-friendliness in its application.

scholarly journals A taxonomic revision of Gaultheria series Trichophyllae (Ericaceae)

2020 ◽  
Vol 14 (2) ◽  
pp. 289-341
Author(s):  
Peter W. Fritsch ◽  
Lu Lu
Keyword(s):  
New Species ◽  
Central Asia ◽  
Taxonomic Revision ◽  
High Elevation ◽  
Key To Species ◽  
East Central ◽  
Present Treatment ◽  
Taxonomic Changes ◽  
Species Descriptions ◽  
The Himalaya

The last taxonomic revision of Gaultheria series Trichophyllae (Ericaceae), a clade of high-elevation species endemic to the Himalaya-Hengduan Shan region of east-central Asia, was published in 1941. Since then, a number of new species have been described and other taxonomic changes have occurred in the group, prompting the need for a comprehensive revision. The present treatment of the series comprises 21 species, including Gaultheria x biluoensis, a newly described hybrid between G. crassifolia and G. major. A key to species and species descriptions is provided, and lectotypes are newly designated for G. cardiosepala, G. gonggashanensis, G. marronina, and G. stenophylla.

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