The taxonomy of the Tarentola mauritanica species complex (Gekkota: Phyllodactylidae): Bayesian species delimitation supports six candidate species

The glassfrogCentrolene buckleyihas been recognized as a species complex. Herein, using coalescence-based species delimitation methods, we evaluate the specific diversity within this taxon. Four coalescence approaches (generalized mixed Yule coalescents, Bayesian general mixed Yule-coalescent, Poisson tree processes, and Bayesian Poisson tree processes) were consistent with the delimitation results, identifying four lineages within what is currently recognized asC. buckleyi. We propose three new candidate species that should be tested with nuclear markers, morphological, and behavioral data. In the meantime, for conservation purposes, candidate species should be considered evolutionary significant units, in light of observed population crashes in theC. buckleyispecies complex. Finally, our results support the validity ofC. venezuelense, formerly considered as a subspecies ofC. buckleyi.

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Species delimitation in the cyanolichen genus Rostania

BMC Evolutionary Biology ◽

10.1186/s12862-020-01681-w ◽

2020 ◽

Vol 20 (1) ◽

Author(s):

Alica Košuthová ◽

Johannes Bergsten ◽

Martin Westberg ◽

Mats Wedin

Keyword(s):

Species Delimitation ◽

A Priori ◽

The Other ◽

Supporting Evidence ◽

Coalescence Model ◽

Guide Tree ◽

Candidate Species ◽

Substantial Correlation ◽

Bayesian Species Delimitation ◽

Β Tubulin

Abstract Background In this study, we investigate species limits in the cyanobacterial lichen genus Rostania (Collemataceae, Peltigerales, Lecanoromycetes). Four molecular markers (mtSSU rDNA, β-tubulin, MCM7, RPB2) were sequenced and analysed with two coalescent-based species delimitation methods: the Generalized Mixed Yule Coalescent model (GMYC) and a Bayesian species delimitation method (BPP) using a multispecies coalescence model (MSC), the latter with or without an a priori defined guide tree. Results Species delimitation analyses indicate the presence of eight strongly supported candidate species. Conclusive correlation between morphological/ecological characters and genetic delimitation could be found for six of these. Of the two additional candidate species, one is represented by a single sterile specimen and the other currently lacks morphological or ecological supporting evidence. Conclusions We conclude that Rostania includes a minimum of six species: R. ceranisca, R. multipunctata, R. occultata 1, R. occultata 2, R. occultata 3, and R. occultata 4,5,6. Three distinct Nostoc morphotypes occur in Rostania, and there is substantial correlation between these morphotypes and Rostania thallus morphology.

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Meiofaunal cryptic species challenge species delimitation: the case of the Monocelis lineata (Platyhelminthes: Proseriata) species complex

Contributions to Zoology ◽

10.1163/18759866-08502001 ◽

2016 ◽

Vol 85 (2) ◽

pp. 123-145 ◽

Cited By ~ 16

Author(s):

Fabio Scarpa ◽

Piero Cossu ◽

Tiziana Lai ◽

Daria Sanna ◽

Marco Curini-Galletti ◽

...

Keyword(s):

Species Delimitation ◽

Species Complex ◽

Taxonomic Resolution ◽

Biodiversity Crisis ◽

Candidate Species ◽

History Of ◽

Adaptive Radiations ◽

Taxonomic Approach ◽

Conservation Concern ◽

Lines Of Evidence

Given the pending biodiversity crisis, species delimitation is a critically important task in conservation biology, but its efficacy based on single lines of evidence has been questioned as it may not accurately reflect species limits and relationships. Hence, the use of multiple lines of evidence has been portrayed as a means to overcome identification issues arising from gene/species tree discordance, morphological convergence or recent adaptive radiations. Here, the integrative taxonomic approach has been used to address the study of the Monocelis lineataspecies complex. The taxonomic resolution of the complex is challenging, as the species lacks sclerotised copulatory structures, which as a rule of thumb aid identification in Proseriata. Eighteen populations, which encompass most of the geographic range of the complex, were studied using morphology, karyology, crossbreeding experiments and molecular analysis. These different markers provided evidence of four (karyology) to eight (morphology) discrete entities, whereas crossings showed various degrees of intersterility among the tested populations. Molecular species delimitation revealed a different number of candidate species, spanning from five (ABGD and K/θ) to 11 (GMYC). Such incongruences reflect the multifaceted evolutionary history of M. lineata s.l.and hamper the full taxonomic resolution of the complex. However, two candidate species were consistently validated by all of the markers and are described as new species: Monocelis algicolanov. sp. and M. exquisitanov. sp. The latter species appear to have a restricted distribution, and the possibility that meiofaunal taxa may be of conservation concern is discussed.

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Species delimitation in the Stenocereus griseus (Cactaceae) species complex reveals a new species, S. huastecorum

PLoS ONE ◽

10.1371/journal.pone.0190385 ◽

2018 ◽

Vol 13 (1) ◽

pp. e0190385 ◽

Cited By ~ 2

Author(s):

Hernán Alvarado-Sizzo ◽

Alejandro Casas ◽

Fabiola Parra ◽

Hilda Julieta Arreola-Nava ◽

Teresa Terrazas ◽

...

Keyword(s):

New Species ◽

Species Delimitation ◽

Species Complex ◽

A New Species

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Atlas of leaf surface micromorphology in Aloe L. (Asphodelaceae) from the Horn of Africa region

Phytotaxa ◽

10.11646/phytotaxa.524.4.3 ◽

2021 ◽

Vol 524 (4) ◽

pp. 261-282

Author(s):

ESHETU FENTAW ◽

KELDA F.V.A. ELLIOTT ◽

SEBSEBE DEMISSEW ◽

DAVID CUTLER ◽

OLWEN M. GRACE

Keyword(s):

Species Delimitation ◽

Plant Material ◽

Species Complex ◽

Leaf Surface ◽

Detailed Comparison ◽

Species Variation ◽

Leaf Epidermis ◽

Horn Of Africa ◽

Surface Micromorphology ◽

Leaf Surface Micromorphology

The confident identification to species rank of fragmentary and sterile plant material is often challenged by the absence of diagnostic characters, which are present in intact specimens, reproductive parts, and plants in habitat. Here, we consider leaf surface micromorphology for the identification of the genus Aloe in the Horn of Africa region. Primary and secondary sculpturing of the leaf epidermis and stomata were characterised from SEM micrographs of 35 taxa representing 31 species of Aloe (Asphodelaceae subfam. Alooideae). Detailed comparison revealed that leaf surface characters are conserved between species and within-species variation is modest. Closely related taxa in the Aloe adigratana—A. camperi—A. sinana species complex could be distinguished using leaf surface micromorphology alone. These characters also guide species delimitation; in the species complex including A. schoelleri and A. steudneri, a narrow circumscription is supported, whereas with A. ankoberensis and A. pulcherrima, a wider circumscription merits consideration. The observed trait combinations are characteristic of plants in xeric environments, with the most notable feature being stomata that are most deeply sunken in species in more arid habitats. Our findings support the use of comparative study of micromorphological leaf surface characters for species identification and taxonomy in the genus Aloe.

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