A Reexamination of Species Boundaries and Hypotheses of Hybridization Concerning Solanum megistacrolobum and S. toralapanum (Solanum sect. Petota, series Megistacroloba): Molecular Data

1994 ◽  
Vol 19 (1) ◽  
pp. 106 ◽  
Author(s):  
Robert B. Giannattasio ◽  
David M. Spooner
2020 ◽  
Vol 189 (4) ◽  
pp. 1249-1312 ◽  
Author(s):  
Alberto Sánchez-Vialas ◽  
Mario García-París ◽  
José L Ruiz ◽  
Ernesto Recuero

Abstract Delimiting species boundaries is a complex challenge usually hindered by overlooked morphological diversification or misinterpretation of geographically structured phenotypic variability. Independent molecular data are extremely useful to characterize and understand such morphological diversity. Morphological and molecular variability of the non-phoretic and apterous, widely distributed, giant blister beetles of the genus Berberomeloe, were investigated within and between lineages across most of the distributional range of the genus. We used two mtDNA gene fragments to characterize genetic variability and to produce a time-calibrated phylogeny of the genus. Our results reveal several mitochondrial lineages, allopatrically, parapatrically and sympatrically distributed. Most clades are not distinguishable between each other based on morphometrics. However, no morphometric overlap is observed between two closely related clades, one of them occurring in sympatry with a distantly congeneric species (B. insignis), suggesting that sympatry could trigger morphological diversification. Although most species share a morphometric space, they can be morphologically identified by a combination of easily observed characteristic qualitative features. Based on the concordance between mtDNA clades and morphological units, we describe six new species of Berberomeloe (B. castuo sp. nov., B. comunero sp. nov., B. indalo sp. nov, B. yebli sp. nov., B. payoyo sp. nov. and B. tenebrosus sp. nov.), revalidate two taxa (B. maculifrons comb. nov. and B. laevigatus comb. nov.) and redefine B. majalis.


2008 ◽  
Vol 33 (3) ◽  
pp. 566-578 ◽  
Author(s):  
Mercedes Ames ◽  
Alberto Salas ◽  
David M. Spooner

There are about 190 wild potato (Solanum L. section Petota Dumort.) species distributed from the southwestern United States to central Argentina and adjacent Chile and Uruguay. The morphological similarity of many of its constituent species has led to widely conflicting taxonomic treatments. Solanum series Piurana Hawkes is one of 21 series recognized in section Petota in the latest comprehensive taxonomic treatment by Hawkes in 1990. They are distributed from southern Colombia, south through Ecuador to central Peru. The limits of the series and validity of its constituent species are unresolved. We provide the first comprehensive morphological phenetic study of the series, to include putatively related species in ser. Conicibaccata, Cuneoalata, Ingifolia, Megistacroloba, Simplicissima, Tuberosa, and Yungasensa, through an examination 188 living germplasm accessions of 33 species, planted in replicated plots in a field station in Andean Peru. Only four morphologically well-defined groups were supported. Continuing work is exploring molecular support for these species in these eight series.


Author(s):  
Thibault Ramage ◽  
Patricia Martins-Simoes ◽  
Gladys Mialdea ◽  
Roland Allemand ◽  
Anne Duplouy ◽  
...  

We report here on the taxonomic and molecular diversity of 10 929 terrestrial arthropod specimens, collected on four islands of the Society Archipelago, French Polynesia. The survey was part of the ‘SymbioCode Project’ that aims to establish the Society Islands as a natural laboratory in which to investigate the flux of bacterial symbionts (e.g., Wolbachia) and other genetic material among branches of the arthropod tree. The sample includes an estimated 1127 species, of which 1098 included at least one DNA-barcoded specimen and 29 were identified to species level using morphological traits only. Species counts based on molecular data emphasize that some groups have been understudied in this region and deserve more focused taxonomic effort, notably Diptera, Lepidoptera and Hymenoptera. Some taxa that were also subjected to morphological scrutiny reveal a consistent match between DNA and morphology-based species boundaries in 90% of the cases, with a larger than expected genetic diversity in the remaining 10%. Many species from this sample are new to this region or are undescribed. Some are under description, but many await inspection by motivated experts, who can use the online images or request access to ethanol-stored specimens.


2021 ◽  
Author(s):  
Mariusz Wiecek ◽  
Lukasz Broda ◽  
Heather Proctor ◽  
Miroslawa Dabert ◽  
Bruce P. Smith ◽  
...  

Arrenurus (Arrenuridae) is the most species-rich genus of mites with about 950 named species that inhabit standing, and to a lesser extent, running water habitats around the world. To date, distinguishing species of Arrenurus has been based on male reproductive morphology. Here, we use morphological and molecular approaches to examine species boundaries among 42 named species of Arrenurus, including four named species that have colour variants (red and green A. americanus, and red and blue A. intermedius, A. manubriator and A. apetiolatus), and two unnamed morphospecies. In this study, we examine male genital structures with the use of SEM techniques, and apply mitochondrial (COI barcode region) and nuclear (28S rRNA) gene fragments to test whether male morphology reflects species boundaries in Arrenurus assessed by molecular analyses. Our results reveal that male reproductive morphology parallels species boundaries as judged by molecular data. We discuss the cases of genetically poorly diversified, yet morphologically clearly defined named species. Moreover, we show that based on the species we examined, colour morphs within otherwise morphologically similar specimens represent within-species variation and, in the absence of other diagnostic traits, colour itself can be misleading in distinguishing species. Our outcomes on molecular taxonomy of Arrenurus provide a background for testing hypotheses about speciation rate in water mites.


Author(s):  
Pradeep K. Divakar ◽  
Ana Crespo

Several obligately sexualy reproducing lichen-forming fungal species are disjunctly distributed in pantropical regions. Here, we aim to re-examine species boundaries within the sexually reproducing, disjunctly distributed species, Hypotrachyna intercalanda. We gathered a three-locus DNA sequence data set of Hypotrachyna subgen. Parmelinopsis, especially including the samples from India, and these data were analysed in a phylogenetic framework. Our results show that specimens of H. intercalanda, as currently circumscribed, do not form a monophyletic group but fall into two well-supported independent clades. Morphological and chemical features were re-evaluated. Corroborating with the phenotypic features, the sample recovered in clade 2 occurring in southern India are described as a new species, viz. Hypotrachyna upretii Divakar and A. Crespo sp. nov. Our study adds a further example of a previously overlooked, geographically distinct, lineage that was uncovered using molecular data. Additionally, our study underlines the need of critical reexamination of phenotypic features of samples falling into different clades.


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