Assessment of traditional versus geometric morphometrics for discriminating populations of the Tropheus moorii species complex (Teleostei: Cichlidae), a Lake Tanganyika model for allopatric speciation

In the subfamily Triatominae, Triatoma exhibits the largest number of species, which are arranged in complexes. For the T.brasiliensis species complex, recent investigations based on results of geometric morphometrics combined with phylogeny have provided evidence that it should be composed of seven species: T.brasiliensis, T.bahiensis, T.juazeirensis, T.lenti, T.melanica, T.petrocchiae, and T.sherlocki, in which T.brasiliensis is divided in two subspecies: T.b.brasiliensis and T.b.macromelasoma. A taxonomic key is presented to identify each taxon. Among members of this complex, T.b.brasiliensis is the most important in an epidemiologic context, due to its high prevalence in natural infection by Trypanosomacruzi combined with a pronounced adaptation to domiciliary habitats. However, some members may be currently invading and colonizing homes, a process known as domiciliation. Therefore, the key presented here may be potentially useful for researchers as well as those involved in vector control measures.

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Allopatric Speciation within a Cryptic Species Complex of Australasian Octopuses

PLoS ONE ◽

10.1371/journal.pone.0098982 ◽

2014 ◽

Vol 9 (6) ◽

pp. e98982 ◽

Cited By ~ 29

Author(s):

Michael D. Amor ◽

Mark D. Norman ◽

Hayley E. Cameron ◽

Jan M. Strugnell

Keyword(s):

Cryptic Species ◽

Species Complex ◽

Allopatric Speciation ◽

Cryptic Species Complex

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Too many species: morphometrics, molecular phylogenetics and genome structure of a Brazilian species complex in Epidendrum (Laeliinae; Orchidaceae) reveal fewer species than previously thought

Botanical Journal of the Linnean Society ◽

10.1093/botlinnean/boaa071 ◽

2020 ◽

Author(s):

Edlley M Pessoa ◽

Joel M P Cordeiro ◽

Leonardo P Felix ◽

Erton M Almeida ◽

Lucas Costa ◽

...

Keyword(s):

Geometric Morphometrics ◽

Genome Size ◽

Species Complex ◽

Molecular Phylogenetics ◽

Genome Structure ◽

Dapi Staining ◽

Canonical Variables ◽

Floral Variation ◽

Brazilian Species ◽

Species Complexes

Abstract In this study, we analyse a species complex in Epidendrum, a mega-diverse Neotropical orchid genus, that is formed by the 11 Brazilian species of the E. difforme group. Although this group (c. 100 taxa) exhibits relatively high levels of floral variation, the Brazilian species are similar, making delimitation problematic. Here we combine molecular (phylogenetics), morphological (geometric morphometrics), genome size and cytogenetic (chromosome counts and CMA/DAPI staining) data to investigate circumscription of these species. Our results were interpreted by looking for congruence of the results as a means to delimit species. The studied taxa appear to be monophyletic, and karyotypically all analysed accessions were 2n = 40. Their 1C values vary from 1.99 ± 07 pg to 2.84 ± 0.12 pg. We did not find evidence for recent polyploidy or dysploidy and, apparently, these phenomena have not been important in the evolution of this species complex. On the other hand, we found high levels of polymorphism for CMA/DAPI banding, and variation in genome size appears to be positively correlated with latitude. Geometric morphometrics indicate that E. sanchezii and E. anatipedium/E. amarajiense are distinct from the remaining species, and three groups of other species can be separated using canonical variables analysis (CVA). Variation in lip shape, genome size and heterochromatin patterns of the taxa are not fully congruent with the phylogenetic analysis, but our results allowed us to delimit with full confidence four species: E. amapense, E. anatipedium (including E. amarajiense), E. pseudodifforme (including E. campaccii and E. thiagoi) and E. sanchezii. Four others will be tentatively maintained but need further study. Our results indicate that it will be necessary to reassess many of the species complexes in the genus using a similar multidisciplinary perspective to evaluate the number of taxa that should be recognized.

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Pronounced Genetic Separation Among Varieties of thePrimula cusickianaSpecies Complex, a Great Basin Endemic

10.1101/2021.03.19.436082 ◽

2021 ◽

Author(s):

Austin Koontz ◽

William D. Pearse ◽

Paul Wolf

Keyword(s):

Genetic Structure ◽

Great Basin ◽

Species Complex ◽

Breeding Systems ◽

Allopatric Speciation ◽

Isolated Populations ◽

Fragmented Habitats ◽

Species Complexes ◽

Varietal Classification ◽

Sky Island

AbstractDistinguishing between unique species and populations with strong genetic structure is a common challenge in population genetics, especially in fragmented habitats where allopatric speciation may be widespread and distinct groups may be morphologically similar. Such is often the case with species complexes across sky island environments. In these scenarios, biogeography may help to explain the relations between species complex members, and RADseq methods are commonly used to compare closely related species across thousands of genetic loci. Here we use RADseq to clarify the relations between geographically distinct but morphologically similar varieties of thePrimula cusickianaspecies complex, and to contextualize past findings of strong genetic structure among populations within varieties. Our genomic analyses demonstrate pronounced separation between isolated populations of this Great Basin endemic, indicating that the current varietal classification of complex members is inaccurate and emphasizing their conservation importance. We discuss how these results correspond to recent biogeographical models used to describe the distribution of other sky island taxa in western North America. Our findings also fit into a wider trend observed for alpinePrimulaspecies complexes, and we consider how heterostylous breeding systems may be contributing to frequent diversification via allopatric speciation in this genus.

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