scholarly journals Markov models provide many solutions for appropriate modeling of inapplicable morphological characters in phylogenetics

2021 ◽  
Author(s):  
Sergei Tarasov

AbstractThis paper describes new models for coding inapplicable characters for phylogenetic analysis with morphological data. I show that these new solutions fall into two categories that require use of different Markov models. Their implementation in the Bayesian framework using popular software RevBayes (Höhna et al., 2016) is provided. A combination of the new models and previous solutions (Tarasov, 2019) is capable to model all main type of dependencies between morphological characters.

Zootaxa ◽  
2008 ◽  
Vol 1736 (1) ◽  
pp. 1 ◽  
Author(s):  
CATHERINE J. YOUNG

The Australian Nacophorini and related taxa are described using a matrix of 116 adult morphological characters. Adults of 72 species are illustrated using photographs and electron micrographs. Subsets of the characters are used to conduct a phylogenetic analysis based on cladistic principles. The adult morphological character set was augmented with 17 characters from eggs and 27 from larvae. The resulting phylogeny is poorly resolved but provides support for many of the relationships recovered by previous molecular analyses of the group, including basal derivations for characters of Larentiinae and Sterrhinae relative to those of the rest of Geometridae, and the monophyly of the Geometrinae + Oenochrominae s. str. Combining 28S D2 datawith morphological data produced a matrix of 60 taxa and 590 characters. The majority rule consensus tree produced by the combined morphological and 28S D2 data is almost identical to the majority rule consensus tree produced by the 28S D2 data alone, except that bootstrap support is lower for most nodes. Common clades obtained from the molecular and morphological trees are described in terms of morphological data. On this basis a concept of the Australian Nacophorini includes Lithinini and Australian Archiearinae. Two robust groups within the tribe also are delimited using characters from all data sources. Comparsions are made between the Nearctic and Neotropical Nacophorini on the basis of shared morphological characters. Australian Boarmiini are defined by synapomorphies.


2021 ◽  
Author(s):  
Robert J Asher ◽  
Martin R Smith

Abstract An unprecedented amount of evidence now illuminates the phylogeny of living mammals and birds on the Tree of Life. We use this tree to measure phylogenetic value of data typically used in paleontology (bones and teeth) from six datasets derived from five published studies. We ask three interrelated questions: 1) Can these data adequately reconstruct known parts of the Tree of Life? 2) Is accuracy generally similar for studies using morphology, or do some morphological datasets perform better than others? 3) Does the loss of non-fossilizable data cause taxa to occur in misleadingly basal positions? Adding morphology to DNA datasets usually increases congruence of resulting topologies to the well corroborated tree, but this varies among morphological datasets. Extant taxa with a high proportion of missing morphological characters can greatly reduce phylogenetic resolution when analyzed together with fossils. Attempts to ameliorate this by deleting extant taxa missing morphology are prone to decreased accuracy due to long-branch artefacts. We find no evidence that fossilization causes extinct taxa to incorrectly appear at or near topologically basal branches. Morphology comprises the evidence held in common by living taxa and fossils, and phylogenetic analysis of fossils greatly benefits from inclusion of molecular and morphological data sampled for living taxa, whatever methods are used for phylogeny estimation.


Plant Disease ◽  
2021 ◽  
Author(s):  
Alma Rosa Solano-Báez ◽  
Santos Gerardo Leyva-Mir ◽  
Moises Camacho-Tapia ◽  
Alfonso Arellano Victoria ◽  
Geremias Rodríguez-Bautista ◽  
...  

Wild blackberry species (Rubus spp. L.; Rosaceae) represents an invaluable source of genes for the generation of new varieties, but also serve as a primary source of disease inoculum. During April of 2020, symptoms of powdery mildew were observed on four populations of wild blackberry species located in the states of Chiapas (16°59'11"N, 92°59'07"W; 16°47'08"N, 92°31'05"W) and Michoacán (19°37'17"N, 100°08'59"W; 19°29'25"N, 101°32'54"W), Mexico. Signs of the pathogen were white powdery masses mainly on the top of new shoots. Symptoms included yellowing, necrosis, and early defoliation of the plants. Hyphae were tin-walled, hyaline, smooth, and 4.0–9.0 mm wide. Appressoria were indistinct -to- nipple-shaped. Conidiophores (n=30, 75–225 × 10.5–13.5 μm) were straight, and unbranched with cylindrical foot cells (n=30, 31.5–158 × 8–13.5 μm), straight, somewhat widening upwards, followed by 1–3 shorter cells. Conidia (n=100; 25.5–38.5 × 9.5–22.5 μm) were catenulate, ellipsoid-ovoid -to- doliiform, containing fibrosin bodies (in 3% KOH). Germ tubes (n=30, 13.5–40.5 × 4.5 μm) emerged laterally, and were unbranched with slightly swollen tips. Chasmothecia were not found. Morphological characters of the fungus in all samples corresponded to the previous descriptions of Podosphaera aphanis by Braun and Cook (2012) and Stevanovi´c et al. (2020). Voucher specimens were deposited in the Department of Agricultural Parasitology Herbarium at the Chapingo Autonomous University under accessions UACH421, UACH423, UACH425, UACH426. To confirm the species identification, the internal transcribed spacer (ITS) of one sample was amplified using the primers ITS5 (White et al. 1990) and P3 (Kusaba and Tsuge, 1995) and sequenced. The sequence was deposited in GenBank (accession number MW988591). A phylogenetic analysis using Bayesian inference and maximum likelihood was performed (Hernández-Restrepo et al. 2018) and included other Podosphaera species (Takamatsu et al. 2010). The sequence from the isolate UACH426 clustered with the strain MUMH1871 of P. aphanis forming a definite clade and remained as a sister taxon of P. pannosa. Pathogenicity was verified through inoculation by gently dusting conidia from one powdery mildew patch onto leaves of five healthy blackberry plants of each specie. The same number of noninoculated plants served as controls. All plants were maintained in a greenhouse at 25–30°C with 75% relative humidity. All inoculated plants developed powdery mildew symptoms after 12 days, whereas no symptoms were observed on noninoculated plants. The fungus recovered from the inoculated plants was morphologically identical to that originally observed on diseased blackberry plants, demonstrating the pathogenicity of the fungus. Based on morphological data and phylogenetic analysis, the fungus was identified as P. aphanis. This fungus has been reported to cause powdery mildew on blackberry plants in Serbia (Stevanovi´c et al. 2020). This is the first report of P. aphanis causing powdery mildew on wild backberry species in Mexico according to Farr and Rossman (2021). The primary source of inoculum of powdery mildew for commercial plantings is wild blackberry plants from noncultivated areas and may warrant control of wild populations.


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.


1997 ◽  
Vol 45 (3) ◽  
pp. 317 ◽  
Author(s):  
D. A. Good ◽  
A. M. Bauer ◽  
R. A. Sadlier

The phylogenetic analysis of allozyme characters within the New Caledonian giant geckos, genus Rhacodactylus, yields a pattern of relationships that is largely congruent with that derived from morphological data. A ‘total evidence’ approach, incorporating 13 allozyme and 29 morphological characters, yields a single most-parsimonious tree with the pattern: R. auriculatus ((R. leachainus (R. ciliatus, R. chahoua)) (R. sarasinorum, R. trachyrhynchus)). A phenetic analysis based on Nei’s genetic distance data results in a similar branching pattern. The genus Pseudothecadactylus is tentatively regarded as valid because allozyme data conflict strongly with morphological data that suggest that these geckos evolved from within Rhacodactylus. Allozymes and available morphological data do not support the recognition of the recently described subspecies R. leachianus henkeli.


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.


2019 ◽  
Author(s):  
Cara Van Der Wal ◽  
Shane T. Ahyong ◽  
Simon Y. W. Ho ◽  
Luana S. F. Lins ◽  
Nathan Lo

The mantis shrimp superfamily Squilloidea, with over 185 described species, is the largest superfamily in the crustacean order Stomatopoda. To date, phylogenetic relationships within this superfamily have been comprehensively analysed using morphological data, with six major generic groupings being recovered. Here, we infer the phylogeny of Squilloidea using a combined dataset comprising 75 somatic morphological characters and four molecular markers. Nodal support is low when the morphological and molecular datasets are analysed separately but improves substantially when combined in a total-evidence phylogenetic analysis. We obtain a well resolved and strongly supported phylogeny that is largely congruent with previous estimates except that the Anchisquilloides-group, rather than the Meiosquilla-group, is the earliest-branching lineage in Squilloidea. The splits among the Anchisquilloides- and Meiosquilla-groups are followed by those of the Clorida-, Harpiosquilla-, Squilla- and Oratosquilla-groups. Most of the generic groups are recovered as monophyletic, with the exception of the Squilla- and Oratosquilla-groups. However, many genera within the Oratosquilla-group are not recovered as monophyletic. Further exploration with more extensive molecular sampling will be needed to resolve relationships within the Oratosquilla-group and to investigate the adaptive radiation of squilloids. Overall, our results demonstrate the merit of combining morphological and molecular datasets for resolving phylogenetic relationships.


Insects ◽  
2020 ◽  
Vol 11 (5) ◽  
pp. 302
Author(s):  
Daniel Winkler ◽  
Eduardo Mateos ◽  
György Traser ◽  
Ferenc Lakatos ◽  
Viktória Tóth

The Collembolan genus Lepidocyrtus is subdivided into up to eight subgenera, of which only Lepidocyrtus s.str. (Bourlet, 1839) and Lanocyrtus (Yoshii & Suhardjono, 1989) are represented by European species. The discovery of unique characters in the European species Lepidocyrtus tomosvaryi (rounded dental tubercle) and L. peisonis (lateral tuft of long filiform chaetae in abdomen III) has only described so far for species of the subgenera Setogaster (Salmon, 1951) and Cinctocyrtus (Yoshii & Suhardjono, 1989) and has raised the need to perform a molecular analysis by involving other representative species of the genus. For this study, phylogenetic analysis of 15 Lepidocyrtus species occurring in the Carpathian Basin were carried out. The analyses, which was based on both concatenated datasets of COII and EF1-α sequences and individual gene sequences, clearly placed L. tomosvaryi within the subgenus Lanocyrtus and L. peisonis within Lepidocyrtus s.srt. European species groups defined on the basis of morphological characters were only partly confirmed by the concatenated and COII analyses because of the splitting of the pallidus–serbicus-group, whereas EF1- α sequences weakly supported this group.


2007 ◽  
Vol 38 (1) ◽  
pp. 1-18 ◽  
Author(s):  
Dana Price

The genus Phanaeus (Scarabaeidae: Scarabaeinae) forms an important part of the dung beetle fauna in much of the Western Hemisphere. Here a phylogeny for Phanaeus , including 49 Phanaeus sp., and 12 outgroup taxa, is proposed. Parsimony analysis of 67 morphological characters, and one biogeographical character produced 629 equally parsimonious trees of 276 steps. Oxysternon , the putative sister taxon is nested well within the subgenus Notiophanaeus , implying that Oxysternon might ultimately need to be synonymized with Phanaeus . Species groups of Edmonds (1994) recovered as monophyletic are paleano , endymion, chalcomelas , tridens , triangularis , and quadridens . An 'unscaled' equal weighting analysis yielded 57,149 equally parsimonious trees of 372 steps. The strict consensus of these trees yielded a monophyletic Phanaeus with the inclusion of Oxysternon . Bootstrap values are relatively low and some clades are unresolved.


2018 ◽  
Vol 92 (4) ◽  
pp. 713-733
Author(s):  
John J. Jacisin ◽  
Samantha S.B. Hopkins

AbstractComplete body fossils of salamanders are relatively rare, but provide critical information on the evolutionary roots of extant urodele clades. We describe new specimens of the fossil salamandridsTaricha oligocenicaVan Frank, 1955, andTaricha lindoeiNaylor, 1979, from the Oligocene Mehama and John Day formations of Oregon that illustrate aspects of skeletal morphology previously unseen in these taxa, and contribute to our understanding of population-level variation. Morphological analysis of these specimens supports the classification ofT.oligocenicaandT.lindoeias two different species, distinct from extantTaricha. Parsimony-based, heuristic analysis of phylogeny using 108 morphological characters for 40 taxa yields different results from a phylogenetic analysis that excludes four taxa known only via vertebrae. Our smaller analysis generally agrees with molecular phylogenies of the family Salamandridae, but with poorer resolution for molgin newts, especially betweenTarichaandNotophthalmus. The analysis including all taxa produced polytomies mostly related to complications from several fossil taxa. The presence or absence of dorsally expanded, sculptured neural spine tables on trunk vertebrae, an important character in past descriptions of fossil salamandrids, appears to be either homoplastic within the Salamandridae, or requires an expansion of characters or character states.Taricha oligocenicaandT. lindoeiare separate species of an at least 33 million-year-old clade, but their relationships with each other and extant North American salamandrids remain unclear with current levels of morphological data. Salamandrid research requires additional morphological data, particularly for the vertebrae and ribs, to better resolve salamandrid evolutionary history through morphological characters.


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