The impact of multiple molecular and morphological data sets on the phylogenetic reconstruction of subtribe Neurachninae (Poaceae: Panicoideae: Paniceae)

2021 ◽  
Author(s):  
E. J. Thompson ◽  
Melodina Fabillo

The taxonomy of Neurachninane has been unstable, with its member genera consisting of Ancistrachne, Calyptochloa, Cleistochloa, Dimorphochloa, Neurachne, Paraneurachne and Thyridolepis, changing since its original circumscription that comprised only the latter three genera. Recent studies on the phylogeny of Neurachninae have focused primarily on molecular data. We analysed the phylogeny of Neurachninae on the basis of molecular data from seven molecular loci (plastid markers: matK, ndhF, rbcL, rpl16, rpoC2 and trnLF, and ribosomal internal transcribed spacer, ITS) and morphological data from 104 morphological characters, including new taxonomically informative micromorphology of upper paleas. We devised an impact assessment scoring (IAS) protocol to aid selection of a tree for inferring the phylogeny of Neurachninae. Combining morphological and molecular data resulted in a well resolved phylogeny with the highest IAS value. Our findings support reinstatement of subtribe Neurachninae in its original sense, Neurachne muelleri and Dimorphochloa rigida. We show that Ancistrachne, Cleistochloa and Dimorphochloa are not monophyletic and Ancistrachne maidenii, Calyptochloa, Cleistochloa and Dimorphochloa form a new group, the cleistogamy group, united by having unique morphology associated with reproductive dimorphism.

Zootaxa ◽  
2004 ◽  
Vol 680 (1) ◽  
pp. 1 ◽  
Author(s):  
ARNE NYGREN

Autolytinae is revised based on available types, and newly collected specimens. Out of 170 nominal species, 18 are considered as incertae sedis, 43 are regarded as junior synonyms, and 25 are referred to as nomina dubia. The relationships of Autolytinae is assessed from 51 morphological characters and 211 states for 76 ingroup-taxa, and 460 molecular characters from mitochondrial 16S rDNA and nuclear 18S rDNA for 31 ingroup-taxa; outgroups include 12 non-autolytine syllid polychaetes. Two analyses are provided, one including morphological data only, and one with combined morphological and molecular data sets. The resulting strict consensus tree from the combined data is chosen for a reclassification. Three main clades are identified: Procerini trib. n., Autolytini Grube, 1850, and Epigamia gen. n. Proceraea Ehlers, 1864 and Myrianida Milne Edwards, 1845 are referred to as nomen protectum, while Scolopendra Slabber, 1781, Podonereis Blainville, 1818, Amytis Savigny, 1822, Polynice Savigny, 1822, and Nereisyllis Blainville, 1828 are considered


2010 ◽  
Vol 41 (3) ◽  
pp. 231-274 ◽  
Author(s):  
Jinzhong Fu ◽  
Owen Lonsdale ◽  
Brian Wiegmann ◽  
Stephen Marshall

AbstractIn this paper, the Clusiidae (Diptera: Schizophora) is analyzed phylogenetically using morphological and molecular data sets, and then redefined on the basis of derived morphological characters. The biology and distribution of the Clusiidae are also reviewed, a key is provided to the World genera, the status of the genus Craspedochaeta Czerny is reevaluated and the type of Heterochroa pictipennis Wulp is discussed. Molecular data sets include genomic DNA sequences from the mitochondrial genes COI (cytochrome oxidase subunit I) and COII (cytochrome oxidase subunit II), the large ribosomal nuclear subunit 28S, and the nuclear protein-coding carbomoylphosphate synthase (CPS) domain of CAD (or “rudimentary”). Genes were analyzed separately, in combination with each other, and in combination with a morphological data set. Although individual molecular data sets often provided conflicting phylogenetic signals, the topologies of the cladograms produced from each data set alone or in combination were largely similar. Most genus-level relationships and several basal divergences were unresolved, but Apiochaeta was very strongly and consistently supported as Sobarocephalinae, not Clusiinae. The Clusiinae and Sobarocephalinae are subsequently redefined using an adjusted morphological tree — retaining Apiochaeta in the Sobarocephalinae — that is only slightly longer (8.4%, or seven steps) than the most parsimonious tree. Our results illustrate the benefits of multiple independent data sets for phylogenetic reconstruction in order to verify and refine existing classifications.


2020 ◽  
Author(s):  
Johannes S Neumann ◽  
Rob Desalle ◽  
Apurva Narechania ◽  
Bernd Schierwater ◽  
Michael Tessler

Abstract There are considerable phylogenetic incongruencies between morphological and phylogenomic data for the deep evolution of animals. This has contributed to a heated debate over the earliest-branching lineage of the animal kingdom: the sister to all other Metazoa (SOM). Here, we use published phylogenomic data sets ($\sim $45,000–400,000 characters in size with $\sim $15–100 taxa) that focus on early metazoan phylogeny to evaluate the impact of incorporating morphological data sets ($\sim $15–275 characters). We additionally use small exemplar data sets to quantify how increased taxon sampling can help stabilize phylogenetic inferences. We apply a plethora of common methods, that is, likelihood models and their “equivalent” under parsimony: character weighting schemes. Our results are at odds with the typical view of phylogenomics, that is, that genomic-scale data sets will swamp out inferences from morphological data. Instead, weighting morphological data 2–10$\times $ in both likelihood and parsimony can in some cases “flip” which phylum is inferred to be the SOM. This typically results in the molecular hypothesis of Ctenophora as the SOM flipping to Porifera (or occasionally Placozoa). However, greater taxon sampling improves phylogenetic stability, with some of the larger molecular data sets ($>$200,000 characters and up to $\sim $100 taxa) showing node stability even with $\geqq100\times $ upweighting of morphological data. Accordingly, our analyses have three strong messages. 1) The assumption that genomic data will automatically “swamp out” morphological data is not always true for the SOM question. Morphological data have a strong influence in our analyses of combined data sets, even when outnumbered thousands of times by molecular data. Morphology therefore should not be counted out a priori. 2) We here quantify for the first time how the stability of the SOM node improves for several genomic data sets when the taxon sampling is increased. 3) The patterns of “flipping points” (i.e., the weighting of morphological data it takes to change the inferred SOM) carry information about the phylogenetic stability of matrices. The weighting space is an innovative way to assess comparability of data sets that could be developed into a new sensitivity analysis tool. [Metazoa; Morphology; Phylogenomics; Weighting.]


1993 ◽  
Vol 24 (2) ◽  
pp. 121-137 ◽  
Author(s):  
Ward C. Wheeler ◽  
Ranhy Bang ◽  
Randall T. Schuh

AbstractThe monophyly of the 7 infraorders of Heteroptera and history of higher group concepts and interrelationships within the Heteroptera are briefly reviewed. Data from 31 morphological characters are combined with 669 bases of 18S nuclear rDNA for 29 taxa, including several outgroups to the Heteroptera, to produce a phylogeny based on the total available evidence. The molecular data alone and in conjunction with morphological data indicate that: the Homoptera are probably not monophyletic; the Auchenorrhyncha are the sister group of Coleorrhyncha + Heteroptera ; the Enicocephalomorpha are the sister group of remaining Heteroptera; the Dipsocoromorpha are the sister group of remaining Heteroptera; the Gerromorpha are the sister group of remaining Heteroptera; the Nepomorpha are the sister group of remaining Heteroptera; the Leptopodomorpha are the sister group of the Cimicomorpha + Pentatomomorpha. The molecular evidence corroborates the morphologically based theory of a sister group relationship between Aradoidea and trichophoran Pentatomomorpha. This scheme deviates from that previously published by Schuh, in which the Leptopodomorpha were treated as the sister group of the Nepomorpha.


2020 ◽  
Vol 130 (3) ◽  
pp. 458-479
Author(s):  
Rodrigo Monjaraz-Ruedas ◽  
Oscar F Francke ◽  
Lorenzo Prendini

Abstract Until recently, the Nearctic short-tailed whipscorpion genus, StenochrusChamberlin, 1922, included 27 species distributed primarily in Mexico, the USA and Central America. Morphological disparity among its species, associated with their adaptation to diverse habitats, raised the question as to whether Stenochrus was monophyletic. The phylogenetic relationships among short-tailed whipscorpions have only recently begun to be explored, and the monophyly of Stenochrus had never been tested. The present contribution provides the first phylogeny of Stenochrus and related genera, based on 61 morphological characters and 2991 aligned DNA nucleotides from two nuclear and two mitochondrial gene markers, for 73 terminal taxa. Separate and simultaneous analyses of the morphological and molecular data sets were conducted with Bayesian Inference, Maximum Likelihood, and parsimony with equal and implied weighting. Terminals represented only by morphological data (‘orphans’) were included in some analyses for evaluation of their phylogenetic positions. As previously defined, Stenochrus sensuReddell & Cokendolpher (1991, 1995) was consistently polyphyletic and comprised eight monophyletic clades, justifying its reclassification into eight genera including Heteroschizomus Rowland, 1973, revalidated from synonymy with Stenochrus by Monjaraz-Ruedas et al. (2019). Rowland & Reddell’s (1980)mexicanus and pecki species groups were consistently paraphyletic. Orphans grouped with the most morphologically similar taxa.


2021 ◽  
Author(s):  
Robin M. D. Beck ◽  
Robert Voss ◽  
Sharon Jansa

The current literature on marsupial phylogenetics includes numerous studies based on analyses of morphological data with relatively limited sampling of Recent and fossil taxa, and many studies based on analyses of molecular data that include a dense sampling of Recent taxa, but relatively few that combine both data types. Another dichotomy in the marsupial phylogenetic literature is between studies that focus on New World taxa, others that focus on Sahulian taxa. To date, there has been no attempt to assess the phylogenetic relationships of the global marsupial fauna, based on combined analyses of morphology and molecular sequences, for a dense sampling of Recent and fossil taxa. For this report, we compiled morphological and molecular data from an unprecedented number of Recent and fossil marsupials. Our morphological data consist of 180 craniodental characters that we scored for 97 species representing every currently recognized Recent genus, 42 additional ingroup (crown-clade marsupial) taxa represented by well-preserved fossils, and 5 outgroups (non-marsupial metatherians). Our molecular data comprise 24.5 kb of DNA sequences from whole-mitochondrial genomes and six nuclear loci (APOB, BRCA1, GHR, RAG1, RBP3 and VWF) for 97 marsupial terminals (the same Recent taxa scored for craniodental morphology) and several placental and monotreme outgroups. The results of separate and combined analyses of these data using a wide range of phylogenetic methods support many currently accepted hypotheses of ingroup (marsupial) relationships, but they also underscore the difficulty of placing fossils with key missing data (e.g., †Evolestes), and the unique difficulty of placing others that exhibit mosaics of plesiomorphic and autapomorphic traits (e.g., †Yalkaparidon). Unique contributions of our study are (1) critical discussions and illustrations of marsupial craniodental morphology, including descriptions and illustrations of some features never previously coded for phylogenetic analysis; (2) critical assessments of relative support for many suprageneric clades; (3) estimates of divergence times derived from tip-and-node dating based on uniquely taxon-dense analyses; and (4) a revised, higher-order classification of marsupials accompanied by lists of supporting craniodental synapomorphies. Far from the last word on these topics, this report lays the foundation for future research that may be enabled by the discovery of new fossil taxa, better-preserved material of previously described taxa, novel morphological characters, and improved methods of phylogenetic analysis.


Phytotaxa ◽  
2021 ◽  
Vol 478 (2) ◽  
pp. 179-200
Author(s):  
SHABIR A. RATHER ◽  
WANG SHU ◽  
MAYANK DHAR DWIVEDI ◽  
CHANG ZHAOYANG

In this study, we explored the evolutionary history and taxonomic treatment of the Caragana opulens complex taking information from morphological and molecular data. The complex consists of three species, C. opulens, C. licentiana and C. kansuensis. Moreover, the morphological characters currently used to differentiate the species present in the complex have been found insignificant and inconsistent and do not help diagnose the species. For the present study, we investigated its range and sampled 139 accessions from the different populations of the genus Caragana and 17 accessions of the complex. DNA sequence data from one nrDNA ITS and one cpDNA trnH-psbA loci were sequenced and analyzed using Maximum Likelihood and Bayesian methods. The resulting phylogenies were congruent in topologies. Based on morphological and molecular data, it is concluded that all three species of the complex are one of the same with significant morphological variations. Hence C. opulens is accepted as the correct name along with C. licentiana and C. kansuensis as synonyms.


Phytotaxa ◽  
2015 ◽  
Vol 205 (3) ◽  
pp. 168 ◽  
Author(s):  
Hyun Lee ◽  
Myung Soo Park ◽  
Paul Eunil Jung ◽  
Jonathan J. Fong ◽  
Seung-Yoon Oh ◽  
...  

A new species belonging to Lactarius subg. Plinthogalus was discovered during a long-term project on the diversity of Korean Lactarius. This species is proposed here as Lactarius cucurbitoides. The status of L. cucurbitoides as a new species is supported by molecular data and morphological features. Phylogenetic analysis based on internal transcribed spacer (ITS) sequences shows that L. cucurbitoides is closely related to L. subplinthogalus, L. friabilis, and L. oomsisiensis, with pairwise distances of 2.8–4.3%. Morphological characters of L. cucurbitoides that distinguish it from these closely related species are a pale yellow to pale orange colored pileus and non-discoloration of white latex. The new species is described and illustrated in the present paper.


2021 ◽  
Vol 21 (1) ◽  
Author(s):  
Jose Barba-Montoya ◽  
Qiqing Tao ◽  
Sudhir Kumar

Abstract Background Matrices of morphological characters are frequently used for dating species divergence times in systematics. In some studies, morphological and molecular character data from living taxa are combined, whereas others use morphological characters from extinct taxa as well. We investigated whether morphological data produce time estimates that are concordant with molecular data. If true, it will justify the use of morphological characters alongside molecular data in divergence time inference. Results We systematically analyzed three empirical datasets from different species groups to test the concordance of species divergence dates inferred using molecular and discrete morphological data from extant taxa as test cases. We found a high correlation between their divergence time estimates, despite a poor linear relationship between branch lengths for morphological and molecular data mapped onto the same phylogeny. This was because node-to-tip distances showed a much higher correlation than branch lengths due to an averaging effect over multiple branches. We found that nodes with a large number of taxa often benefit from such averaging. However, considerable discordance between time estimates from molecules and morphology may still occur as  some intermediate nodes may show large time differences between these two types of data. Conclusions Our findings suggest that node- and tip-calibration approaches may be better suited for nodes with many taxa. Nevertheless, we highlight the importance of evaluating the concordance of intrinsic time structure in morphological and molecular data before any dating analysis using combined datasets.


2021 ◽  
Author(s):  
Jose Barba-Montoya ◽  
Qiqing Tao ◽  
Sudhir Kumar

Abstract Background: Matrices of morphological characters are frequently used for dating species divergence times in systematics. In some studies, morphological and molecular character data from living taxa are combined, whereas others use morphological characters from extinct taxa as well. We investigated whether morphological data produce time estimates that are concordant with molecular data. If true, it will justify the use of morphological characters alongside molecular data in divergence time inference.Results: We systematically analyzed three empirical datasets from different species groups to test the concordance of species divergence dates inferred using molecular and discrete morphological data from extant taxa as test cases. We found a high correlation between their divergence time estimates, despite a poor linear relationship between branch lengths for morphological and molecular data mapped onto the same phylogeny. This was because node-to-tip distances showed a much higher correlation than branch lengths due to an averaging effect over multiple branches. We found that nodes with a large number of taxa often benefit from such averaging. However, considerable discordance between time estimates from molecules and morphology may still occur because some deeper nodes show a large time differences between these two types of data.Conclusions: Our findings suggest that node- and tip-calibration approaches may be better suited for nodes with many taxa. Nevertheless, we highlight the importance of evaluating the concordance of time structure in morphological and molecular data before any dating analysis using combined datasets.


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