Fern nothogenera and ×Lepinema, a new hybrid genus between Ellipinema and Lepisorus (Polypodiaceae)

Phytotaxa ◽  
2020 ◽  
Vol 455 (4) ◽  
pp. 262-266
Author(s):  
LIANG ZHANG ◽  
LI-BING ZHANG

The biological species concept is not exclusively applicable in many groups of organisms including ferns. Interspecific fern hybrids are not rare: there are 16 intergeneric hybrid genera in ferns confirmed with molecular data. Here we add one more hybrid genus in the tribe Lepisoreae of Polypodiaceae, ×Lepinema, formed via hybridization between parents in two genera: Ellipinema and Lepisorus.

Zootaxa ◽  
2009 ◽  
Vol 2301 (1) ◽  
pp. 29-54 ◽  
Author(s):  
FRANK E. RHEINDT ◽  
JAMES A. EATON

The question of how to define a species continues to divide biologists. Meanwhile, the application of different species concepts has led to disparate taxonomic treatments that confound conservationists and other biologists. The most widely followed guidelines to species designation in avian and other vertebrate taxonomy are Ernst Mayr’s Biological Species Concept (BSC) and Joel Cracraft’s version of the Phylogenetic Species Concept (PSC). Although the BSC is considered to be more conservative in its assignment of species status, there is a lack of research demonstrating differences in taxonomic treatment between the BSC and the PSC with reference to a multi-taxon multi-trait study system. We examined the case of five traditionally recognized species of shrike-babbler (Pteruthius) that have recently been divided into 19 species under the PSC. Re-analyzing previous morphological and molecular data and adding new vocal data, we propose a BSC classification of 9 species. However, taking into consideration geographic gaps in the sampling regime, we contend that additional data will likely reduce discrepancies between the total numbers of species designated under the PSC and BSC. The current PSC species total is a likely overestimate owing to species diagnosis based on characters that erroneously appear to be unique to a taxon at low sample size. The current BSC species total as here proposed is a likely underestimate on account of the conservative designation of taxa as subspecies in equivocal cases, e.g. where BSC species status is potentially warranted but may be masked by insufficient data.


Zootaxa ◽  
2006 ◽  
Vol 1293 (1) ◽  
pp. 1 ◽  
Author(s):  
PATRICK DAVID ◽  
GERNOT VOGEL ◽  
S. P. VIJAYAKUMAR ◽  
NICOLAS VIDAL

The brown Asian pitvipers of the genus Trimeresurus related to Trimeresurus puniceus (informal Trimeresurus puniceus-complex) are revised on the basis of morphological and molecular analyses. Variation in morphological characters were investigated among 119 specimens from 62 populations of the whole range of the pitvipers currently known as Trimeresurus puniceus (Boie, 1827), Trimeresurus borneensis (Peters, 1872) and Trimeresurus brongersmai Hoge, 1969. Molecular and morphological analyses clearly differentiate two groups of taxa, referrable to the informal Trimeresurus puniceus-group and Trimeresurus borneensis-group, and confirm the distinct specific status of T. puniceus and T. borneensis. Morphological univariate and multivariate analyses differentiate six clusters of populations that are morphologically diagnosable, of which five are here considered to represent independent lineages and one is placed incertae sedis pending the availability of further specimens. These clusters are considered to be distinct species following the Biological Species Concept and the Phylogenetic Species Concept. One of them is described as a new species, Trimeresurus andalasensis spec. nov. (T. borneensis-group), which includes populations from northern Sumatra. Trimeresurus wiroti Trutnau, 1981 is revalidated to accommodate populations from Thailand and West Malaysia. Trimeresurus borneensis is here considered endemic to Borneo. Trimeresurus puniceus is known from Java and from South Sumatra, but the taxonomy of this species in Sumatra is left unresolved. Also left unresolved is the taxonomic position of specimens from western Sumatra and the Mentawai Archipelago, and from the Natuna Islands and Anamba Islands. Although belonging to the T. puniceus-group, they show some differences to other specimens of the group. They are not referred to any taxon pending the collection of additional specimens. Lastly, Trimeresurus brongersmai is confirmed as a valid species from the Mentawai Archipelago. A key to these taxa is provided.


Zootaxa ◽  
2016 ◽  
Vol 4200 (1) ◽  
pp. 83 ◽  
Author(s):  
KARL-L. SCHUCHMANN ◽  
ANDRÉ-A. WELLER ◽  
DIETMAR JÜRGENS

We analyzed geographic variation, biogeography, and intrageneric relationships of racket-tail hummingbirds Ocreatus (Aves, Trochilidae). Presently, the genus is usually considered monospecific, with O. underwoodii including eight subspecies (polystictus, discifer, underwoodii, incommodus, melanantherus, peruanus, annae, addae), although up to three species have been recognized by some authors. In order to evaluate the current taxonomy we studied geographic variation in coloration, mensural characters, and behavioral data of all Ocreatus taxa. We briefly review the taxonomic history of the genus. Applying the Biological Species Concept, species delimitation was based on a qualitative-quantitative criteria analysis including an evaluation of character states. Our results indicate that the genus should be considered a superspecies with four species, the monotypic Ocreatus addae, O. annae, and O. peruanus, and the polytypic O. underwoodii (including the subspecies underwoodii, discifer, incommodus, melanantherus, polystictus). In this taxonomic treatment, O. annae becomes an endemic species to Peru and O. addae is endemic to Bolivia. We recommend additional sampling of distributional, ethological, and molecular data for an improved resolution of the evolutionary history of Ocreatus. 


2021 ◽  
Vol 102 (4) ◽  
Author(s):  
Yiyuan Li ◽  
Angela C. O’Donnell ◽  
Howard Ochman

Mosquito-borne arboviruses, including a diverse array of alphaviruses and flaviviruses, lead to hundreds of millions of human infections each year. Current methods for species-level classification of arboviruses adhere to guidelines prescribed by the International Committee on Taxonomy of Viruses (ICTV), and generally apply a polyphasic approach that might include information about viral vectors, hosts, geographical distribution, antigenicity, levels of DNA similarity, disease association and/or ecological characteristics. However, there is substantial variation in the criteria used to define viral species, which can lead to the establishment of artificial boundaries between species and inconsistencies when inferring their relatedness, variation and evolutionary history. In this study, we apply a single, uniform principle – that underlying the Biological Species Concept (BSC) – to define biological species of arboviruses based on recombination between genomes. Given that few recombination events have been documented in arboviruses, we investigate the incidence of recombination within and among major arboviral groups using an approach based on the ratio of homoplastic sites (recombinant alleles) to non-homoplastic sites (vertically transmitted alleles). This approach supports many ICTV-designations but also recognizes several cases in which a named species comprises multiple biological species. These findings demonstrate that this metric may be applied to all lifeforms, including viruses, and lead to more consistent and accurate delineation of viral species.


PLoS ONE ◽  
2013 ◽  
Vol 8 (6) ◽  
pp. e68267 ◽  
Author(s):  
Lélia Lagache ◽  
Jean-Benoist Leger ◽  
Jean-Jacques Daudin ◽  
Rémy J. Petit ◽  
Corinne Vacher

2005 ◽  
Vol 176 (2) ◽  
pp. 221-225
Author(s):  
Jean Génermont

Abstract In 1980, Henri Tintant advocated the usefulness of the biological species concept in paleontology. At this time, this concept was still accepted by many neontologists, but it was already rather severely criticized by some others. In fact, a lot of new concepts appeared in the course of the following two decades. While a few ones are mere adjustments of the biological concept, for instance taking in account ecological criteria, in such a way that it could be applied to clonal organisms, some others, which were developed in connexion with the cladistic theory of taxonomy, are truly new from a conceptual point of view. The diagnosable version of the phylogenetic species concept is somewhat reminiscent of Simpson’s evolutionary species concept, since it accepts phyletic speciation as well as survival of the stem species after a cladogenetic event. One of its more criticizable features, from a cladistic point of view, is that the species are not necessarilly monophyletic. On another hand, according to the monophyly version of the phylogenetic species concept, species are recognized rather subjectively as monophyletic taxa revealed by some previous cladistic analysis dealing with operational taxonomic units. A consensus on the definition of species cannot be expected, since all concepts related to the biological one are founded on population grouping on the basis of potentially identical evolutionary fates, while those which are related to cladistic taxonomy are exclusively concerned with historical features.


2010 ◽  
Vol 365 (1547) ◽  
pp. 1853-1863 ◽  
Author(s):  
James Mallet

The development of what became known as the biological species concept began with a paper by Theodosius Dobzhansky in 1935, and was amplified by a mutualistic interaction between Dobzhansky, Alfred Emerson and Ernst Mayr after the second world war. By the 1950s and early 1960s, these authors had developed an influential concept of species as coadapted genetic complexes at equilibrium. At this time many features of species were seen as group advantages maintained by selection to avoid breakdown of beneficial coadaptation and the ‘gene pool’. Speciation thus seemed difficult. It seemed to require, more so than today, an external deus ex machina , such as allopatry or the founder effect, rather than ordinary within-species processes of natural selection, sexual selection, drift and gene flow. In the mid-1960s, the distinctions between group and individual selection were clarified. Dobzhansky and Mayr both understood the implications, but their views on species changed little. These group selectionist ideas now seem peculiar, and are becoming distinctly less popular today. Few vestiges of group selectionism and species-level adaptationism remain in recent reviews of speciation. One wonders how many of our own cherished views on evolution will seem as odd to future biologists.


2013 ◽  
Vol 22 (21) ◽  
pp. 5382-5396 ◽  
Author(s):  
Francesco Cicconardi ◽  
Pietro P. Fanciulli ◽  
Brent C. Emerson

2021 ◽  
Author(s):  
Maria J.A. Creighton ◽  
Alice Q. Luo ◽  
Simon M. Reader ◽  
Arne Ø. Mooers

ABSTRACTSpecies are the main unit used to measure biodiversity, but different preferred diagnostic criteria can lead to very different delineations. For instance, named primate species have more than doubled since 1982. Such increases have been termed “taxonomic inflation” and have been attributed to the widespread adoption of the ‘phylogenetic species concept’ (PSC) in preference to the previously popular ‘biological species concept’ (BSC). Criticisms of the PSC have suggested taxonomic inflation may be biased toward particular taxa and have unfavourable consequences for conservation. Here, we explore predictors of taxonomic inflation across primate taxa since the initial application of the PSC nearly 40 years ago. We do not find evidence that diversification rate, the rate of lineage formation over evolutionary time, is linked to inflation, contrary to expectations if the PSC identifies incipient species. We also do not find evidence of research effort in fields where work has been suggested to motivate splitting being associated with increases in species numbers among genera. To test the suggestion that splitting groups is likely to increase their perceived risk of extinction, we test whether genera that have undergone more splitting have also observed a greater increase in their proportion of threatened species since the introduction of the PSC. We find no cohesive signal of inflation leading to higher threat probabilities across primate genera. Overall, this analysis sends a positive message that threat statuses of primate species are not being overwhelmingly affected by splitting in line with what has recently been reported for birds. Regardless, we echo warnings that it is unwise for conservation to be reliant on taxonomic stability. Species (however defined) are not independent from one another, thus, monitoring and managing them as such may not meet the overarching goal of conserving biodiversity.


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