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Microlicieae are a monophyletic tribe comprising seven genera: Chaetostoma , Lavoisiera , Microlicia s.s. , Poteranthera , Rhynchanthera , Stenodon and Trembleya. Microlicia s.s. includes 172 species predominantly distributed in the campo rupestre of Brazil. Its delimitation is complex because the generic boundaries, mostly with Lavoisiera and Trembleya , are unclear. Here we present a phylogenetic analysis for Microlicieae focusing on Microlicia s.s. , with the specific goals: (1) to test the monophyly of Microlicia s.s. ; (2) to investigate morphological characters that could help in circumscribing clades and/or genera in the tribe and (3) to provide an appropriate classification for Microlicia s.s. and related genera. This study was based on plastid (atpF-atpH , trnS-trnG), nuclear ribosomal (nrITS, nrETS) and nuclear low-copy (waxy) DNA sequences, through maximum likelihood and Bayesian inference analyses. The history of 12 morphological characters was estimated based on ancestral state reconstruction analyses. Our analysis shows Microlicia s.s. to be paraphyletic with Chaetostoma , Lavoisiera , Stenodon and Trembleya nested in it. Most characters traditionally used to diagnose these genera are homoplastic. We propose the inclusion of these four genera in a broadly circumscribed Microlicia s.l. and provide new combinations and names for their species. As here defined, Microlicieae has three genera, Rhynchanthera , Poteranthera and Microlicia s.l. Microlicia s.l. being the fourth richest genus in Melastomataceae with c. 245 species. [ABSTRACT FROM AUTHOR]

Phylogenetic relationships within the sinica-group of macaques based on morphological, behavioral, and molecular characteristics have remained controversial. The Nepal population of Assam macaques (Macaca assamensis) (NPAM), the westernmost population of the species, is morphologically distinct but has never been used in phylogenetic analyses. Here, the phylogenetic relationship of NPAM with other congeners was tested using multiple mitochondrial and Ychromosomal loci. The divergence times and evolutionary genetic distances among macaques were also estimated. Results revealed two major mitochondrial DNA clades of macaques under the sinica-group: the first clade included M. thibetana, M. sinica, and eastern subspecies of Assam macaque (M. assamensis assamensis); the second clade included M. radiata together with species from the eastern and central Himalaya, namely, M. leucogenys, M. munzala, and NPAM. Among the second-clade species, NPAM was the first to diverge from the other members of the clade around 1.9 million years ago. Our results revealed that NPAM is phylogenetically distinct from the eastern Assam macaques and closer to other species and hence may represent a separate species. Because of its phylogenetic distinctiveness, isolated distribution, and small population size, the Nepal population of sinica-group macaques warrants detailed taxonomic revision and high conservation priority. [ABSTRACT FROM AUTHOR]

We hypothesized that the mitogenome of Gammarus lacustris (GL), native to the Qinghai-Tibet Plateau, might exhibit genetic adaptations to the extreme environmental conditions associated with high altitudes (greater than 3000 m). To test this, we also sequenced the mitogenome of Gammarus pisinnus (GP), whose native range is close to the Tibetan plateau, but at a much lower altitude (200–1500 m). The two mitogenomes exhibited conserved mitochondrial architecture, but low identity between genes (55% atp8 to 76.1% cox1). Standard (homogeneous) phylogenetic models resolved Gammaridae as paraphyletic, but ‘heterogeneous’ CAT-GTR model as monophyletic. In indirect support of our working hypothesis, GL, GP and Gammarus fossarum exhibit evidence of episodic diversifying selection within the studied Gammaroidea dataset. The mitogenome of GL generally evolves under a strong purifying selection, whereas GP evolves under directional (especially pronounced in atp8) and/or relaxed selection. This is surprising, as GP does not inhabit a unique ecological niche compared to other gammarids. We propose that this rapid evolution of the GP mitogenome may be a reflection of its relatively recent speciation and heightened non-adaptive (putatively metabolic rate-driven) mutational pressures. To test these hypotheses, we urge sequencing mitogenomes of remaining Gammarus species populating the same geographical range as GP.

A phylogenetic analysis on specimen level was made in possible support of a multivariate analysis of the Calamus javensis complex. Nine species, at some time recognized within the complex, and several recognisable forms were included. The phylogenetic markers used were the nuclear 5S spacer (5S nrDNA) and the chloroplast Maturase K (matK). The Bayesian analysis showed that only 5S provided some resolution. The 50 % majority rule consensus showed one major polytomy with a few supported groups, which were mainly morphologically unsupported pairs of specimens. However, one group, the form C. tenompokensis (the only distinct group in a multivariate analysis) is morphologically distinct and phylogenetically monophyletic and can be recognized as a species. Of all other recognizable forms, we only consider C. acuminatus to be regarded as a variety as it was not supported in the morphometric analysis. [ABSTRACT FROM AUTHOR]

Abstract Background Recent phylogenies of deer mice, genus Peromyscus, have relied heavily on mitochondrial markers. These markers provided resolution at and below the level of species groups, but relationships among species groups and Peromyscus affiliated genera have received little support. Here, we present the mitochondrial genomes of 14 rodents and infer the phylogeny of Peromyscus and related taxa. Results Our analyses support results from previous molecular phylogenies, but also yield support for several previously unsupported nodes throughout the Peromyscus tree. Our results also confirm several instances of paraphyly within the clade and suggest additional taxonomic work will be required to clarify some relationships. Conclusions Our findings greatly enhance our understanding of the evolution of Peromyscus providing support for previously unsupported relationships. However, the results also highlight the need to address paraphyly that may exist in this clade.

Molecular data has become a powerful tool for species delimitation, particularly among those that present limited morphological differences; while the mitochondrial genome, with its moderate length, low cost of sequencing and fast lineage sorting, has emerged as a practical data set. Due to the limited morphological differences among the closely related species of Carbula Stål 1865, the species boundaries between Carbula abbreviata (Motschulsky, 1866), Carbula humerigera (Uhler, 1860), and Carbula putoni (Jakovlev, 1876) have remained particularly unclear. In this study, we applied two phylogenetic reconstruction methods to two data sets (mitogenome and COI) to assess the phylogeny of Carbula distributed in Asia, and five species delimitation methods to determine the boundaries between East Asian Carbula species. Our phylogenetic analyses showed Carbula to be paraphyletic; the seven known species distributed within East Asia to form a single monophyletic group, and within this, C. abbreviata, C. humerigera, C. putoni and middle-type to comprise a C. humerigera species complex. Our results show that mitogenome data alone, while effective in the differentiation of more distantly related Carbula species, is not sufficient to accurately delimit the species within this newly described complex., (© 2023 Wiley Periodicals LLC.)

In order to assess the phylogenetic relationships of three rare species belonging to tribe Parablenniini was carried out, along the Coast of Oman Sea. Based on the type of habitats the specimens of Blenniid were collected from three sampling sites in the intertidal zones by Scoop and hand net in low tide and in sub-tidal zones by scuba diving and hand from 3, 6, 9, and 12m depths in September to March 2013. Totally 30 fish samples collected and deposited to the lab for further investigation. Based on the available identification keys and morphometric characters three species of Parablennius cornutus, Parabelennius pilicorn, Scartella emarginata were identified. DNA was extracted from the basal tissue of the first dorsal fin, subsequently by using a specific fish primer 700 bp of Cytochrome Oxidase C subunit 1 (CO1)was amplified in polymerase chain reaction (PCR) and sequenced. After comparison of Iranian Blenniid species CO1 sequence with sequence of 25 species from GenBank, was concluded that Iranian species are paraphyletically in the clade Parablenniini and sub-clads of Scartella and Parablennius. Since the relationship of Parablennius with other blenniids is the subject of many studies to resolve the conflicts and ambiguities among them we selected these genera to investigate the sister group relationship among them as well as other genera and clads. This is the first time that morphologic and molecular study of the two genera Parablennius and Scartella have been carried out in Iran.

The genus Brucella is a globally distributed intracellular pathogen that affects animals and humans and presents low genetic variability, which is a challenge for its phylogenetic reconstruction. Genus differentiation originally occurred due to its preference for a certain host and analyses throughout the years to classify the genus Brucella and its strains, depended on the techniques used, the number of strains or the methods of phylogenetic reconstruction . Its history goes from recognizing the entire genus as unique B. mellitensis species with multiple varieties, to recognizing more than ten species . This review shows the journey through the techniques that have been used to differentiate the genus Brucella, which, although they have generated clarity in the grouping of some species, still leaves doubts in related to the oldest species, their divergence and the type of grouping of the new species discovered . The application of new technologies such as phylogenomics is contributing to solve these questions.

Over two centuries of taxonomic studies on the species rich genus Phyllanthus have culminated in a broad and complicated classification with many subgenera and (sub)sections. Past taxonomic work has only focused on local revisions, mostly because of the size of the genus. In this study we aim to summarize most of the taxonomic work in a list containing the infrageneric delimitations of Phyllanthus. This work will serve as a reference, placing most currently recognized species in subgenera and if possible, in sections for further study. Here we recognize 880 species of Phyllanthus, classified in 18 subgenera, 70 sections and 14 subsections. A few taxonomic changes are necessary to reconcile published phylogenetic data with the current classification. Subsections Callidisci and Odontadenii are raised to sectional rank, while section Eleutherogynium and section Physoglochidion are reduced to subsections and P. oxycarpus is transferred to the genus Glochidion. A provisional key for the subgeneric classification of Phyllanthus is provided. [ABSTRACT FROM AUTHOR]

Abstract: The genus Triptilion is endemic to central Chile, the Mendoza Province and western Patagonia in Argentina. It is currently composed of seven species: T. achilleae, T. benaventii, T. berteroi, T. capillatum, T. cordifolium, T. gibbosum, and T. spinosum. The main objectives of this paper were to determine the phylogenetic relationships of species of Triptilion. We also traced the evolution of annual and perennial life‐forms. Historically a close relationship has been described between genera Triptilion and Nassauvia. Phylogenetic analysis of the genus Triptilion and more closely related genera was undertaken using two nuclear (ITS, ETS) and two chloroplast (trnL‐F, rpl32‐trnL) markers. The topology of the Bayesian inference tree shows that the genus Triptilion is paraphyletic, because Nassauvia lagascae, the only representative of Nassauvia section Caloptilium grouped with T. achilleae, Clade I. The other species of Triptilion form two clades: Clade II composed of T. cordifolium and T. gibbosum and Clade III that includes T. benaventii, T. berteroi, T. capillatum, and T. spinosum. The genus Triptilion originated and diverged during the Miocene. The results of the life history reconstructions indicate that the common ancestor of Triptilion and Nassauvia was perennial. The annual habit appears to be derived in Triptilion. The life‐form of the common ancestor of Triptilion was ambiguous; it may have been annual or perennial. [ABSTRACT FROM AUTHOR]

How genome divergence eventually leads to speciation is a topic of prime evolutionary interest. Genomic islands of elevated divergence are frequently reported between diverging lineages, and their size is expected to increase with time and gene flow under the speciation-with-gene-flow model. However, such islands can also result from divergent sorting of ancient polymorphisms, recent ecological selection regardless of gene flow, and/or recurrent background selection and selective sweeps in low-recombination regions. It is challenging to disentangle these nonexclusive alternatives, but here we attempt to do this in an analysis of what drove genomic divergence between four lineages comprising a species complex of desert poplar trees. Within this complex we found that two morphologically delimited species, Populus euphratica and Populus pruinosa, were paraphyletic while the four lineages exhibited contrasting levels of gene flow and divergence times, providing a good system for testing hypotheses on the origin of divergence islands. We show that the size and number of genomic islands that distinguish lineages are not associated with either rate of recent gene flow or time of divergence. Instead, they are most likely derived from divergent sorting of ancient polymorphisms and divergence hitchhiking. We found that highly diverged genes under lineage-specific selection and putatively involved in ecological and morphological divergence occur both within and outside these islands. Our results highlight the need to incorporate demography, absolute divergence measurement, and gene flow rate to explain the formation of genomic islands and to identify potential genomic regions involved in speciation. [ABSTRACT FROM AUTHOR]

The utility of microsatellites (SSRs) in reconstructing phylogenies is largely confined to studies below the genus level, due to the potential of homoplasy resulting from allele size range constraints and poor SSR transferability among divergent taxa. The eucalypt genus Corymbia has been shown to be monophyletic using morphological characters, however, analyses of intergenic spacer sequences have resulted in contradictory hypotheses- showing the genus as either equivocal or paraphyletic. To assess SSR utility in higher order phylogeny in the family Myrtaceae, phylogenetic relationships of the bloodwood eucalypts Corymbia and related genera were investigated using eight polymorphic SSRs. Repeat size variation using the average square and Nei's distance were congruent and showed Corymbia to be a monophyletic group, supporting morphological characters and a recent combination of the internal and external transcribed spacers dataset. SSRs are selectively neutral and provide data at multiple genomic regions, thus may explain why SSRs retained informative phylogenetic signals despite deep divergences. We show that where the problems of size-range constraints, high mutation rates and size homoplasy are addressed, SSRs might resolve problematic phylogenies of taxa that have diverged for as long as three million generations or 30 million years.

The taxonomic status and phylogenetic placement of the monotypic genus Trichoneuron is studied using DNA sequences of three plastid-coding genes. Trichoneuron was originally assigned to Thelypteridaceae but has been considered to be a synonym of Lastreopsis in recent treatments. In this study, the proposed relationship of Trichoneuron to Lastreopsis was tested using a comprehensive taxa sampling of Dryopteridaceae. Our results strongly support the recognition of Trichoneuron as a distinct genus belonging to Dryopteridaceae. Trichoneuron does not group together with Lastreopsis. Instead the genus was found to be sister to the Neotropical genus Polystichopsis. This sister relationship is supported by the occurrence of long pluricellular hairs attached to the rachis of both genera. The morphological distinction of Trichoneuron from Lastreopsis is backed by the structure of the adaxial groove of rachis-costa junction and the hairs at abaxial side of leaf axes. The Polystichopsis- Trichoneuron clade was found to form the sister clade to an entirely Neotropical clade comprising Polybotrya and its relatives. The new subfamily Polybotryoideae is introduced based on the presented observations. In turn, the newly recovered sister relationship between Polystichopsis and Trichoneuron provides evidence for geographic disjunctions involving the Caribbean islands and the Indo-Burma biodiversity hotspot. [ABSTRACT FROM AUTHOR]

Malaxideae is a larger cosmopolitan orchid tribe consisting of nearly 2 000 species and is distributed world-wide,excluding the polar and desert regions, tt is abundant in the tropical regions, particularly in Australia, and the tropical Asia, Southeast Asia, the tropical Americas and Africa. Molecular and morphological analyses have been performed to establish the phylogenetic relationships within this tribe. However, the subtribe and intergeneric relationships remain unclear, and the genus definition of this tribe is considerably controversial. The maximum parsimony, maximum likelihood and Bayesian inference analyses were performed based on the combined sequences of the nuclear ITS and chloroplatt matK genes of 133 taxa (10 other allied species as outgroups), which represent nearly all of the major genera of the Malaxideae. These results suggested that Malaxideae could be divided into three clades, the epiphytic Oberoniinae, the terrestrial Liparidinae, and a terrestrial Crepidium clade. The Oberoniinae and Liparidinae could be divided into six genera and five genera respectively, and Crepidium clade camposes of four genera. The subtribe Ypsilorchidinae should be attributed to Oberoniinae. Disticholiparis should be removed because it shared the same type with. The phylogenetic relationship of Crepidium and Dienia is monophyletic. although they have different lip structures. In addition, two new species found in Southwest China and northern Vietnam. Platystyliparis malipoensis G. D. Tang .X . Y. Zhuang & Z. J . Liu and Cestichis pingtati G. D. Tang .X . Y. Zhuang & Z. J. Liu. were described based on the molecular analysis and morphological observation. [ABSTRACT FROM AUTHOR]

Abstract: A molecular analysis was performed on 56 taxa in the orchid genus Cypripedium using nrDNA ITS and five chloroplast regions (trnH-psbA, atpI-atpH, trnS-trnfM, trnL-F spacer, and the trnL intron). The genus Cypripedium was confirmed as monophyletic. Our data provided strong support for monophyletic grouping of eight infrageneric sections (Subtropica, Obtusipetala, Trigonopedia, Sinopedilum, Bifolia, Flabelinervia, Arietinum, and Cypripedium) defined in earlier taxonomic treatments, and paraphyletic grouping of two sections (Irapeana and Retinervi). Within the genus Cypripedium, the first divergent lineage consisted of two Mesomaerican species, and subsequently the Cypripedium debile lineage from eastern Asia was split. Our study did not support the notion that two Asian species (Cypripedium subtropicum and Cypripedium singchii) were closely related to either Mesoamerican Cypripedium irapeanum or North American Cypripedium californicum, as indicated by previous interpretations based on morphological evidences. In addition, one pair of vicariant species, Cypripedium plectrochilum (eastern Asia) and Cypripedium arietinum (North America), unique to section Arietinum, was confirmed. Furthermore, within the monophyletic section Cypripedium two previously recognized subsections, Cypripedium and Macrantha, were shown to be paraphyletic. Our results suggested that this section split into two groups based on distribution (North America vs. Eurasia) instead of such previously used, morphological traits as flower color, and the shape of the lips (labellum) and lateral petals. [Copyright &y& Elsevier]

Abstract: Since the first attempts to classify the evolutionary history of trypanosomes, there have been conflicting reports regarding their true phylogenetic relationships and, in particular, their relationships with other vertebrate trypanosomatids, e.g. Leishmania sp., as well as with the many insect parasitising trypanosomatids. Perhaps the issue that has provided most debate is that concerning the monophyly (or otherwise) of genus Trypanosoma and, even with the advent of molecular methods, the findings of numerous studies have varied significantly depending on the gene sequences analysed, number of taxa included, choice of outgroup and phylogenetic methodology. While of arguably limited applied importance, resolution of the question as to whether or not trypanosomes are monophyletic is critical to accurate evaluation of competing, mutually exclusive evolutionary scenarios for these parasites, namely the ‘vertebrate-first’ or ‘insect-first’ hypotheses. Therefore, a new approach, which could overcome previous limitations was needed. At its most simple, the problem can be defined within the framework of a trifurcated tree with three hypothetical positions at which the root can be placed. Using BLASTp and whole-genome gene-by-gene phylogenetic analyses of Trypanosoma brucei, Trypanosoma cruzi, Leishmania major and Naegleria gruberi, we have identified 599 gene markers – putative homologues – that were shared between the genomes of these four taxa. Of these, 75 homologous gene families that demonstrate monophyly of the kinetoplastids were identified. We then used these data sets in combination with an additional outgroup, Euglena gracilis, coupled with large-scale gene concatenation and diverse phylogenetic techniques to investigate the relative branching order of T. brucei, T. cruzi and L. major. Our findings confirm the monophyly of genus Trypanosoma and demonstrate that <1% of the analysed gene markers shared between the genomes of T. brucei, T. cruzi and L. major reject the hypothesis that the trypanosomes form a monophyletic group. [Copyright &y& Elsevier]

Abstract: Divergent paralogs can create both obstacles and opportunities for phylogenetic reconstruction. Phylogenetic relationships among eucalypt genera have been incongruent among datasets in previous studies, where morphological characters supported monophyly of the genus Corymbia, while intergenic spacers of the nuclear ribosomes (ITS) and chloroplast loci (trnL, trnH, psbA) showed Corymbia as either equivocal or paraphyletic. Ribosomal DNA occurs in multiple copies in a genome. We cloned and sequenced the nrITS to investigate if gene duplication was the cause of incongruence among trees in the eucalypts. Three ITS riboforms, two of them widespread, were recovered within some genomes. One of the ITS riboforms recovered a robust phylogeny showing Corymbia as a monophyletic genus, corroborating the evidence from morphology, fossil data, a recent ITS/ETS dataset and microsatellites (SSRs). Compelling evidence suggested that this divergent riboform is a pseudogene, i.e., non-functional paralog: comparatively lower GC content suggesting lower structural stability, deamination-like mutations at potential methylation sites, lack of conserved helices and hairpins and conspicuously lower thermodynamic stability in secondary structures. Phylogenies from the apparently functional riboform retained Corymbia as paraphyletic. We show here that pseudogenes can recover a well-corroborated phylogeny whereas their functional paralogs show misleading hypotheses. We explain that phylogenetic signals may be obscured when functional constraints in ITS necessitate compensatory mutations in the secondary structure helices involved in RNA transcription, whereas pseudogenes mutate under neutrality. [Copyright &y& Elsevier]

In the most recent morphology-based taxonomic classification of African Oxalis L., 206 species were recognized in nine indigenous southern African sections. A subsequent palynological review of these taxa conflicted with their taxonomic classification. In the present study, phylogenetic relationships within section Angustatae subsection Lineares are re-assessed, using plastid trnL-F non-coding DNA sequence data. The results of this study clearly indicate that, based on the DNA evidence, subsection Lineares is non-monophyletic. Previously hypothesized relationships within the subsection are also refuted. In contrast, molecular and palynological data are highly congruent, and both differ substantially from the current morphological classification for subsection Lineares. [ABSTRACT FROM AUTHOR]

Brachaspis robustus is an endangeredgrasshopper endemic to South Island, NewZealand. It is both rare and localised;occupying low altitude floodplain terraces andbraided riverbeds of the Mackenzie Basin. Thisis in stark contrast to the two other speciesin this genus ( B. nivalis and B.collinus) which occupy montane habitats.Mitochondrial and nuclear sequence data wereemployed to explore genetic diversity andphylogenetic relationships of populations of Brachaspis with a view to establishingthe status of B. robustus. Molecularevidence indicates that Brachaspisprobably radiated during the Pliocene and thatdivisions within the genus relate more tospatial distribution developed during thePleistocene than to ecology. The mitochondrial(Cytochrome oxidase I) and nuclear (ITS)sequence data indicate that Brachaspisnivalis is divided into northern and southernpopulations. The northern clade is furthersubdivided geographically. The southern cladecomprises alpine populations of B.nivalis and includes the lowland B.robustus. Additionally, it is observed thatsome morphological features previously thoughtto be specific to B. robustus also occurin members of the southern B. nivalisclade. It is suggested that the taxon B.robustus should include all of the southern Brachaspis populations. But it is arguedthat the absence of genetic evidencedistinguishing the endangered population doesnot preclude it from conservation effort. Acombination of morphological and habitatpeculiarities indicate that the survival of B. robustus ( sensu lato) isimportant to the maintenance of diversity. [ABSTRACT FROM AUTHOR]

A recently published study analyzed the phylogenetic relationship between the genera Centrodinium and Alexandrium, confirming an earlier publication showing the genus Alexandrium as paraphyletic. This most recent manuscript retained the genus Alexandrium, introduced a new genus Episemicolon, resurrected two genera, Gessnerium and Protogonyaulax, and stated that: "The polyphyly [sic] of Alexandrium is solved with the split into four genera". However, these reintroduced taxa were not based on monophyletic groups. Therefore this work, if accepted, would result in replacing a single paraphyletic taxon with several non-monophyletic ones. The morphological data presented for genus characterization also do not convincingly support taxa delimitations. The combination of weak molecular phylogenetics and the lack of diagnostic traits (i.e., autapomorphies) render the applicability of the concept of limited use. The proposal to split the genus Alexandrium on the basis of our current knowledge is rejected herein. The aim here is not to present an alternative analysis and revision, but to maintain Alexandrium. A better constructed and more phylogenetically accurate revision can and should wait until more complete evidence becomes available and there is a strong reason to revise the genus Alexandrium. The reasons are explained in detail by a review of the available molecular and morphological data for species of the genera Alexandrium and Centrodinium. In addition, cyst morphology and chemotaxonomy are discussed, and the need for integrative taxonomy is highlighted., (Crown Copyright © 2020. Published by Elsevier B.V. All rights reserved.)

We hypothesized that the mitogenome of Gammarus lacustris (GL), native to the Qinghai-Tibet Plateau, might exhibit genetic adaptations to the extreme environmental conditions associated with high altitudes (greater than 3000 m). To test this, we also sequenced the mitogenome of Gammarus pisinnus (GP), whose native range is close to the Tibetan plateau, but at a much lower altitude (200-1500 m). The two mitogenomes exhibited conserved mitochondrial architecture, but low identity between genes (55% atp8 to 76.1% cox1 ). Standard (homogeneous) phylogenetic models resolved Gammaridae as paraphyletic, but 'heterogeneous' CAT-GTR model as monophyletic. In indirect support of our working hypothesis, GL, GP and Gammarus fossarum exhibit evidence of episodic diversifying selection within the studied Gammaroidea dataset. The mitogenome of GL generally evolves under a strong purifying selection, whereas GP evolves under directional (especially pronounced in atp8 ) and/or relaxed selection. This is surprising, as GP does not inhabit a unique ecological niche compared to other gammarids. We propose that this rapid evolution of the GP mitogenome may be a reflection of its relatively recent speciation and heightened non-adaptive (putatively metabolic rate-driven) mutational pressures. To test these hypotheses, we urge sequencing mitogenomes of remaining Gammarus species populating the same geographical range as GP., Competing Interests: We declare we have no competing interests., (© 2020 The Authors.)

Ambulycini are a cosmopolitan tribe of the moth family Sphingidae, comprised of 10 genera, 3 of which are found in tropical Asia, 4 in the Neotropics, 1 in Africa, 1 in the Middle East, and 1 restricted to the islands of New Caledonia. Recent phylogenetic analyses of the tribe have yielded conflicting results, and some have suggested a close relationship of the monobasic New Caledonian genus Compsulyx Holloway, 1979 to the Neotropical ones, despite being found on opposite sides of the Pacific Ocean. Here, we investigate relationships within the tribe using full mitochondrial genomes, mainly derived from dry-pinned museum collections material. Mitogenomic data were obtained for 19 species representing nine of the 10 Ambulycini genera. Phylogenetic trees are in agreement with a tropical Asian origin for the tribe. Furthermore, results indicate that the Neotropical genus Adhemarius Oiticica Filho, 1939 is paraphyletic and support the notion that Orecta Rothschild & Jordan 1903 and Trogolegnum Rothschild & Jordan, 1903 may need to be synonymized. Finally, in our analysis the Neotropical genera do not collectively form a monophyletic group, due to a clade comprising the New Caledonian genus Compsulyx and the African genus Batocnema Rothschild & Jordan, 1903 being placed as sister to the Neotropical genus Protambulyx Rothschild & Jordan, 1903. This finding implies a complex biogeographic history and suggests the evolution of the tribe involved at least two long-distance dispersal events. [ABSTRACT FROM AUTHOR]

ABSTRACT In the present response paper, the article entitled "Morphometric variation of the Herichthys bartoni (Bean, 1892) species group (Teleostei: Cichlidae): How many species comprise H. labridens (Pellegrin, 1903)?" by Mejía et al . 2015 is critically reviewed. The current review pinpoints some of the more conspicuous conceptual inconsistencies and fundamental errors found in the study by Mejía et al . (2015), It is contended that the authors fail to provide any new insights into the complex biogeography and evolutionary history of the Nosferatu and Herichthys genus groups, and that while results of their Cox1 molecular analysis are comparable to those by De la Maza-Benignos et al . (2015), the conclusions of the two studies are not comparable. In addition, it is contested that, whereas the designation of genus Nosferatu by De la Maza-Benignos et al . (2015) was found on the principles of the biological and phylogenetic species concepts, the rejection of the genus by Mejía et al . (2015) is solely based "on the presence of (overlapping) morphometric characters" between genera. The assumption by Mejía et al . (2015),that because their geometric morphometrics analysis failed to provide separation of species, then Nosferatu genus does not correspond to a valid taxon; and their suggesting geometric morphometrics "as useful tool to discriminate species, because it allows to propose diagnostic characters" were not supported by their results. While Mejía et al . present some interesting thoughts on the systematics of Nosferatu , they unfortunately fail to provide any data that can be objectively assessed as relevant to motivate any changes in the current taxonomy.

How genome divergence eventually leads to speciation is a topic of prime evolutionary interest. Genomic islands of elevated divergence are frequently reported between diverging lineages, and their size is expected to increase with time and gene flow under the speciation-with-gene-flow model. However, such islands can also result from divergent sorting of ancient polymorphisms, recent ecological selection regardless of gene flow, and/or recurrent background selection and selective sweeps in low-recombination regions. It is challenging to disentangle these nonexclusive alternatives, but here we attempt to do this in an analysis of what drove genomic divergence between four lineages comprising a species complex of desert poplar trees. Within this complex we found that two morphologically delimited species, Populus euphratica and Populus pruinosa , were paraphyletic while the four lineages exhibited contrasting levels of gene flow and divergence times, providing a good system for testing hypotheses on the origin of divergence islands. We show that the size and number of genomic islands that distinguish lineages are not associated with either rate of recent gene flow or time of divergence. Instead, they are most likely derived from divergent sorting of ancient polymorphisms and divergence hitchhiking. We found that highly diverged genes under lineage-specific selection and putatively involved in ecological and morphological divergence occur both within and outside these islands. Our results highlight the need to incorporate demography, absolute divergence measurement, and gene flow rate to explain the formation of genomic islands and to identify potential genomic regions involved in speciation., Competing Interests: The authors declare no conflict of interest., (Copyright © 2018 the Author(s). Published by PNAS.)