scholarly journals On the spore ornamentation of the microsoroid ferns (microsoroideae, polypodiaceae)

2020 ◽  
Author(s):  
Chi-Chuan Chen ◽  
Ho-Yih Liu ◽  
Cheng-Wei Chen ◽  
Harald Schneider ◽  
Jaakko Hyvönen
Keyword(s):  
Ancestral State ◽  
Spore Morphology ◽  
Spore Surface ◽  
Old World ◽  
Spore Ornamentation ◽  
The Third ◽  
Surface Ornamentation ◽  
Ancestral States ◽  
Phylogenetic Hypotheses ◽  
Five Tribes

AbstractMicrosoroideae is the third largest of the six subfamilies of Polypodiaceae, containing over 180 species. These ferns are widely distributed in the tropical and subtropical regions of the Old World and Oceania. We documented the spore ornamentation and integrated these data into the latest phylogenetic hypotheses, including a sampling of 100 taxa representing each of 17 major lineages of microsoroid ferns. This enabled us to reconstruct the ancestral states of the spore morphology. The results show verrucate ornamentation as an ancestral state for Goniophlebieae and Lecanoptereae, globular for Microsoreae, and rugulate surface for Lepisoreae. In addition, spore ornamentation can be used to distinguish certain clades of the microsoroid ferns. Among all five tribes, Lecanoptereae show most diversity in spore surface ornamentation.

A systematic evaluation of basidiospore symmetry and tegumentation in hypogeous and gasteroid Russulales

1988 ◽  
Vol 66 (12) ◽  
pp. 2561-2573 ◽  
Author(s):  
Steven L. Miller
Keyword(s):  
Light Microscope ◽  
Spore Wall ◽  
Systematic Evaluation ◽  
Spore Morphology ◽  
Spore Surface ◽  
Layer 2 ◽  
Spore Walls ◽  
Poorly Differentiated ◽  
Surface Ornamentation ◽  
Dark Blue

Spore wall architecture and ontogeny of ornamentation in several genera and species of hypogeous and gasteroid Russulales are similar to those described previously for agaricoid Lactarius lignyotellus. Spore walls are composed of four layers, each differing in thickness and electron density. Layer 2 is electron transparent and corresponds to a dark blue, amyloid layer when mounted in Melzer's iodine reagent and viewed with the light microscope. Establishment of spore symmetry may be regulated by the hilar appendix body, which is a poorly differentiated cytoplasmic region in the hilar appendix of asymmetric spores of Macowanites luteolus, Elasmomyces russuloides, and Zelleromyces versicaulus but which is absent in symmetric spores of Z. sculptisporus, Martellia subochracea, and Gymnomyces yubaensis. A continuum in spore morphology from truly symmetric to asymmetric is evident in spores from individual sporocarps of many species of the Russulales. The variation in spore symmetry and spore surface ornamentation has clouded taxonomic concepts in the Russulales. Systematically, development of orthotropic and heterotropic spores has been regarded as two distinct end points of evolution, when they are likely terms describing degrees of the same phenomenon. The current circumscription of families and genera in the Russulales based on spore symmetry, therefore, appears to be artificial.

scholarly journals Investigation of ancestral alleles in the Bovinae subfamily

BMC Genomics ◽  
2021 ◽  
Vol 22 (1) ◽  
Author(s):  
Maulana M. Naji ◽  
Yuri T. Utsunomiya ◽  
Johann Sölkner ◽  
Benjamin D. Rosen ◽  
Gábor Mészáros
Keyword(s):  
Extreme Points ◽  
Genetic Mutation ◽  
Zebu Cattle ◽  
Ancestral State ◽  
Initial State ◽  
High Count ◽  
Environmental Pressures ◽  
Ancestral States ◽  
Productive Traits ◽  
Species Specific

Abstract Background In evolutionary theory, divergence and speciation can arise from long periods of reproductive isolation, genetic mutation, selection and environmental adaptation. After divergence, alleles can either persist in their initial state (ancestral allele - AA), co-exist or be replaced by a mutated state (derived alleles -DA). In this study, we aligned whole genome sequences of individuals from the Bovinae subfamily to the cattle reference genome (ARS.UCD-1.2) for defining ancestral alleles necessary for selection signatures study. Results Accommodating independent divergent of each lineage from the initial ancestral state, AA were defined based on fixed alleles on at least two groups of yak, bison and gayal-gaur-banteng resulting in ~ 32.4 million variants. Using non-overlapping scanning windows of 10 Kb, we counted the AA observed within taurine and zebu cattle. We focused on the extreme points, regions with top 0. 1% (high count) and regions without any occurrence of AA (null count). High count regions preserved gene functions from ancestral states that are still beneficial in the current condition, while null counts regions were linked to mutated ones. For both cattle, high count regions were associated with basal lipid metabolism, essential for survival of various environmental pressures. Mutated regions were associated to productive traits in taurine, i.e. higher metabolism, cell development and behaviors and in immune response domain for zebu. Conclusions Our findings suggest that retaining and losing AA in some regions are varied and made it species-specific with possibility of overlapping as it depends on the selective pressure they had to experience.

Spore wall development in Sphagnum lescurii

1982 ◽  
Vol 60 (11) ◽  
pp. 2394-2409 ◽  
Author(s):  
Roy Curtiss Brown ◽  
Betty E. Lemmon ◽  
Zane B. Carothers
Keyword(s):  
Plasma Membrane ◽  
Outer Layer ◽  
Mature Spore ◽  
Outer Wall ◽  
Spore Wall ◽  
Spore Surface ◽  
Proximal Surface ◽  
Complex Development ◽  
Surface Ornamentation ◽  
Cortical System

The spore wall of Sphagnum is unique in the Bryophyta. The Sphagnum spore exine consists of two layers: an inner, lamellate layer (A layer) and a thick, homogenous, outer layer (B layer). The exine of other mosses consists of only the outermost homogenous layer and, at most, a thin ill-defined opaque layer. During development of the A-layer exine and the intine, a cortical system of evenly spaced microtubules underlies the plasma membrane. The ontogeny of the wall layers is not strictly centripetal. The A-layer exine develops evenly around the young spore immediately after cytokinesis. As the intine is deposited centripetally inside it, the homogenous B-layer exine is deposited outside the first-formed A layer. The B layer is responsible for the primary sculpturing of the spore surface. The mature spore is covered by an outermost perine, which is responsible for secondary surface ornamentation. A trilaesurate aperture develops on the proximal surface of each spore after deposition of the A layer. Ridges of the laesurae develop as a result of deposition of thick areas of intine. The ridges are eventually covered by the outer wall layers, whereas the fissure is covered only by the A layer and a very thin B-layer exine. The complex development of the trilaesurate aperture is evidence that the structure is not merely a mechanically induced "trilete mark" or "scar" resulting from compression of tetrahedrally arranged spores within a sporocyte wall.

Phylogenetics of the mycoheterotrophic genus Thismia (Thismiaceae: Dioscoreales) with a focus on the Old World taxa: delineation of novel natural groups and insights into the evolution of morphological traits

2020 ◽  
Vol 193 (3) ◽  
pp. 287-315 ◽  
Author(s):  
Ekaterina A Shepeleva ◽  
Mikhail I Schelkunov ◽  
Michal Hroneš ◽  
Michal Sochor ◽  
Martin Dančák ◽  
...  
Keyword(s):  
Significant Proportion ◽  
Morphological Diversity ◽  
Taxonomic Revision ◽  
Morphological Characters ◽  
Morphological Description ◽  
Molecular Evidence ◽  
Ancestral State ◽  
Old World ◽  
Molecular Phylogenetic ◽  
Floral Characters

Abstract Thismia is a genus of > 80 mycoheterotrophic species characterized by a peculiar appearance and complex floral morphology. A significant proportion of the species and morphological diversity of Thismia has only been uncovered in the past two decades, and new discoveries continue to be made. Given that many new data have recently become available, and the most comprehensive taxonomic revision of the genus from 1938 addresses less than half of the currently known species, previous hypotheses for species relationships and infrageneric taxonomic classification in Thismia was in need of review. Extensive molecular phylogenetic studies of Thismia at the genus level have never been presented. We investigate the phylogenetic relationships of 41 species (and one variety) of Thismia from the Old World. Our study comprises 68 specimens (for 28 of which the data were newly generated), including outgroup taxa broadly representing Thismiaceae (= Burmanniaceae p.p. sensuAPG IV, 2016), and is based on two nuclear and one mitochondrial marker. We use maximum likelihood and Bayesian inference to infer relationships among the taxa. We also constructed a morphological dataset of 12 mostly floral characters, comparing these characters to hypotheses based on molecular evidence to identify putative synapomorphies for major clades and to discuss hypotheses regarding the evolution of structural traits in the genus. Our analyses indicate that the majority of currently accepted infrageneric taxa of Thismia are polyphyletic. We find support for the monophyly of the Old World group, in which we recognize five well-supported lineages (clades); the only New World species studied appears to be related to the Neotropical genus Tiputinia. Ancestral state reconstructions demonstrate that the evolution of most morphological characters was homoplastic, but we identify characters that provide each of the five clades of Old World Thismia with a unique morphological description. The geographical distribution of the species under study is also shown to be consistent with the major clades. Our investigation provides a phylogenetic basis for the development of a novel sectional classification of Thismia reflecting morphological and geographical traits.

scholarly journals Morphology of immature stages of Paraegidium costalimai (Coleoptera: Scarabaeidae: Orphninae) and remarks on egg-busters in Scarabaeidae first‑instar larvae

2020 ◽  
Author(s):  
Rafael Clayton De Jesus e Sousa ◽  
Juares Fuhrmann
Keyword(s):  
Comparative Study ◽  
New World ◽  
Immature Stages ◽  
Old World ◽  
The Third ◽  
First Instar ◽  
Third Instar Larvae

Studies about the immature stages of Orphninae (Coleoptera: Scarabaeidae) species are scarce. The subfamily includes 214 species, but only 5 have the immature stages described: Chaetonyx robustus liguricus Mariani, 1946, Hybalus benoiti Tournier, 1864, H. rotroui Petrovitz, 1964 and Triodontus nitidulus (Guérin, 1844) from Old World; and Aegidium cribratum Bates, 1887 from the New World. The Neotropical genus Paraegidium Vulcano, Pereira & Martinez, 1966 encompass five species, mainly recorded from Brazil. Herein, the immature stages of P. costalimai Vulcano, Pereira & Martinez, 1966 are described and illustrated, along with remarks on the presence of egg-buster in Scarabaeidae first-instar larvae. A key to the third-instar larvae of known Orphninae and a comparative study of chaetotaxy are also provided.

scholarly journals Plausibility of inferred ancestral phenotypes and the evaluation of alternative models of limb evolution in scincid lizards

2009 ◽  
Vol 6 (3) ◽  
pp. 354-358 ◽  
Author(s):  
Adam Skinner ◽  
Michael S. Y. Lee
Keyword(s):  
Alternative Model ◽  
Ancestral State ◽  
Alternative Models ◽  
Ancestral States ◽  
Best Fit ◽  
Ancestral Character States ◽  
Limb Morphology

Phylogenetic approaches to inferring ancestral character states are becoming increasingly sophisticated; however, the potential remains for available methods to yield strongly supported but inaccurate ancestral state estimates. The consistency of ancestral states inferred for two or more characters affords a useful criterion for evaluating ancestral trait reconstructions. Ancestral state estimates for multiple characters that entail plausible phenotypes when considered together may reasonably be assumed to be reliable. However, the accuracy of inferred ancestral states for one or more characters may be questionable where combined reconstructions imply implausible phenotypes for a proportion of internal nodes. This criterion for assessing reconstructed ancestral states is applied here in evaluating inferences of ancestral limb morphology in the scincid lizard clade Lerista . Ancestral numbers of digits for the manus and pes inferred assuming the models that best fit the data entail ancestral digit configurations for many nodes that differ fundamentally from configurations observed among known species. However, when an alternative model is assumed for the pes, inferred ancestral digit configurations are invariably represented among observed phenotypes. This indicates that a suboptimal model for the pes (and not the model providing the best fit to the data) yields accurate ancestral state estimates.

scholarly journals Comment on Smaers et al. (2016): A nonviable phylogenetic comparative method hampered by circularity, inaccuracy, and bias

2016 ◽  
Author(s):  
Randi H. Griffin ◽  
Gabriel S. Yapuncich
Keyword(s):  
Brownian Motion ◽  
Simulation Study ◽  
Narrow Range ◽  
Comparative Method ◽  
Ancestral State ◽  
Phylogenetic Comparative Method ◽  
Constant Variance ◽  
Rates Of Evolution ◽  
Branch Lengths ◽  
Ancestral States

AbstractSmaers, Mongle & Kandler (2016) (Biological Journal of the Linnean Society, 118: 78-94) introduced a new phylogenetic comparative method, multiple variance Brownian motion (mvBM), for reconstructing ancestral states given a phylogenetic tree and continuous trait data. The authors conducted a simulation study and argued that mvBM outperforms constant variance Brownian motion (BM) when rates of evolution vary across the phylogeny. In this comment, we argue that mvBM is not a viable statistical method because it is fundamentally a circular analysis that overfits phylogenetic branch lengths to the data. We further argue that the comparison of mvBM to BM under conditions where the assumptions of BM are clearly violated is not an informative performance analysis, and that the simulation study of Smaers et al. (2016) exaggerates the performance of mvBM by focusing on a narrow range of simulation conditions and reporting aggregated accuracy metrics that obscure severe inaccuracy and bias in its ancestral state estimates. Our arguments are supported by simulation results. We conclude that mvBM is not a viable phylogenetic comparative method.

scholarly journals INVENTARISASI DAN KAJIAN PALINOLOGI JENIS-JENIS TUMBUHAN PAKU (PTERODOFITA) EPIFIT DI KAWASAN UNIVERSITAS RIAU, PROVINSI RIAU

2019 ◽  
Vol 19 (2) ◽  
pp. 214
Author(s):  
Nery Sofiyanti ◽  
Putri Handayani Harahap
Keyword(s):  
Electron Microscopy ◽  
Scanning Electron Microscopy ◽  
Digital Data ◽  
Spore Morphology ◽  
Spore Type ◽  
Mature Leaves ◽  
Digital Microscope ◽  
Fern Species ◽  
Surface Ornamentation ◽  
Scanning Electron

Abstrak : Tumbuhan paku  (Pteridofita) epifit banyak di jumpai di kawasan Universitas Riau. Karakteristik spora pada tumbuhn apaku memegang peranan penting dalam kajian taksonomi. Penelitian ini bertujuan untuk mengidentifikasi jenis-jenis pteridofita epifit di kawasan ini dan  mengkarakterisasi sporanya. Metode pengambilan sampel dilakukan menggunakan metode eksplorasi. Setiap jenis yang dijumpai didokumentasikan, dibuat herbarium, dideskripsi dan diidentifikasi. Spora dikoleksi dari daun yang sudah dewasa dan dibuat preparat menggunakan metode asetolisis. Preparat spora diamati dan didokumentasikan menggunakan mikroskop digital. Data yang diperoleh kemudian disajikan dalam bentuk gambar dan tabel serta dianalisis secara deskriptif. Hasil inventarisasi paku epifit di kawasan Universitas Riau mengidentifikasi 18 jenis paku epifit, yang tergolong ke dalam 6 famili yaitu Aspleniaceae, Davalliaceae, Nephrolepidaceae, Polypodiaceae Pteridaceae and Thelypteridaceae. Namun kajian palinologi hanya dilakukan pada 11 jenis yang sudah menghasilkan spora. Hasil pengamatan spora menunjukan bahwa semua jenis paku epifit mempunyai tipe dasar spora monolete, berbentuk ginjal dan hanya mempunyai satu laesura pada bagian ventral. Ukuran spora yang dijumpai adalah besar dan sangat besar, dengan ornamentasi permukaan Lohpat, verukat berpapila verukat, tuberkulat, ekinat pendek dan ekinat panjang. Morfologi spora yang ditemukan pada penelitian ini menunjukan karakteristik yang berbeda pada setiap jenis. Namun masih perlu dilanjutkan pengamatan menggunakan Scanning Electron Microscopy untuk mendapatkan oramentasi lebih detilKata kunci : paku epifit, palinologi, spora, monolete, UNRI Abstract : Ephypitic ferns are commonly found in University of Riau area. Spore characteristics play important role in taxonomical words. This study aimed to identify ephypitic pteridophyte species from this area and characterize their spore. Samples were collected using exploration method, and were then documented, prepared for herbarium, described and identified. Spore grains were collected from mature leaves and prepared by using acetolysis method. The spores were then observed and documented using digital microscope. Data were presented in figures and tables and describtively analized. The inventory of ephypitic ferns from University of Riau area identified a total of 18 fern species belong to 6 families, i.e. Aspleniaceae, Davalliaceae, Nephrolepidaceae, Polypodiaceae, Pteridaceae and Thelypteridaceae. Palinologycal study had been carried out from 11 species that produced spore. We observed the basic spore type of examined ephypitic ferns, monolete, with reniform shape and one laesura at the ventral part. The size of spore observed were big and very big spore, with surface ornamentation Lohpate, papillous verucate,  verucate,  tuberculate,, short echinate and long echinate. Spore morphology observed in this study showed the characteristic among the examined species. The further study using Scanning Electron Microscopy is neccesary to obtain detail spore ornamentation.Keywords: ephypitic fern, palynology, spore, monolete, UNRI

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