Modified sperm ultrastructure and some data on spermiogenesis in Provortex tubiferus (Plathelminthes, Rhabdocoela): phylogenetic implications for the Dalyellioida

Zoomorphology ◽  
1995 ◽  
Vol 115 (1) ◽  
pp. 41-49 ◽  
Author(s):  
B. Sopott-Ehlers ◽  
U. Ehlers
Keyword(s):  
Sperm Ultrastructure ◽  
Phylogenetic Implications

scholarly journals Sperm ultrastructure of Pochazia shantungensis (Chou & Lu) and Ricania speculum (Walker) (Hemiptera, Ricaniidae) with phylogenetic implications

ZooKeys ◽  
2019 ◽  
Vol 880 ◽  
pp. 43-59
Author(s):  
Zhen Jiang ◽  
Jianing Liu ◽  
Daozheng Qin
Keyword(s):  
Neck Region ◽  
Mature Spermatozoon ◽  
Current Evidence ◽  
Sperm Ultrastructure ◽  
Transmission Electron ◽  
Phylogenetic Implications ◽  
Dense Substance ◽  
The Individual ◽  
Relationship Of ◽  
Centriole Adjunct

The sperm ultrastructure of two ricaniid species, Pochazia shantungensis (Chou & Lu) and Ricania speculum (Walker), was investigated using light and transmission electron microscopy. Both species have monoflagellate sperm, the shape and ultrastructure of the mature spermatozoon of these two species are similar in morphology, and 128 spermatozoa are organized into sperm bundles with their heads embedded in a homogenous matrix forming the spermatodesmata. The individual sperm is filiform and includes the head, neck and flagellum. The head is needle-like, with a bilayer acrosome and an inferior elongated nucleus which is formed of homogeneously compact and electron-dense chromatin. The neck region is indistinct and is comprised of the centriole and centriole adjunct with a homogeneous dense substance. The long flagellum has the typical 9 + 9 + 2 axoneme microtubule pattern and two symmetrical mitochondrial derivatives with an orderly array of cristae flanking both sides, and a pair of well-developed fishhook-shaped accessory bodies. Current evidence shows that ricaniid species have D-shaped mitochondrial derivatives in cross-section and a serrated electron-dense region. The phylogenetic relationship of Fulgoroidea with other superfamilies in Auchenorrhyncha is briefly discussed.

The sperm ultrastructure of Caurinus dectes Russell (Mecoptera: Boreidae) and its phylogenetic implications

2013 ◽  
Vol 45 (6) ◽  
pp. 397-401 ◽  
Author(s):  
Loren K. Russell ◽  
Romano Dallai ◽  
Marco Gottardo ◽  
Rolf G. Beutel
Keyword(s):  
Sperm Ultrastructure ◽  
Phylogenetic Implications

Architecture of Radiolitid Rudist (Mollusca) Shell-Wall Structures and its Phylogenetic Implications

1975 ◽  
Vol 33 ◽  
pp. 686-687
Author(s):  
David H. Sturm ◽  
Bob F. Perkins
Keyword(s):  
Phylogenetic Relationships ◽  
Outer Wall ◽  
Shell Microstructure ◽  
Shell Wall ◽  
Wall Structures ◽  
Phylogenetic Implications ◽  
Cellular Wall ◽  
Superfamily Analysis ◽  
Central Texas

Each of the seven families of rudists (Mollusca, Bivalvia, Hippuritacea) is characterized by distinctive shell-wall architectures which reflect phylogenetic relationships within the superfamily. Analysis of the complex, calcareous, cellular wall of the attached valve of the radiolite rudist Eoradiolites davidsoni (Hill) from the Comanche Cretaceous of Central Texas indicates that its wall architecture is an elaboration of the simpler monopleurid rudist wall and supports possible radiolite-monopleurid relationships.Several well-preserved specimens of E. davidsoni were sectioned, polished, etched, and carbon and gold coated for SEM examination. Maximum shell microstructure detail was displayed by etching with a 0.7% HC1 solution from 80 to 100 seconds.The shell of E. davidsoni comprises a large, thick-walled, conical, attached valve (AV) and a small, very thin, operculate, free valve (FV) (Fig. 1a). The AV shell is two-layered with a thin inner wall, in which original structures are usually obliterated by recrystallization, and a thick, cellular, outer wall.

NEW EVIDENCE OF EARLY HYBOCRINID TEGMENS; PHYLOGENETIC IMPLICATIONS

2017 ◽  
Author(s):  
Thomas E. Guensburg ◽  
◽  
James Sprinkle
Keyword(s):  
Phylogenetic Implications ◽  
New Evidence

scholarly journals Uncovering dynamic evolution in the plastid genome of seven Ligusticum species provides insights into species discrimination and phylogenetic implications

2021 ◽  
Vol 11 (1) ◽  
Author(s):  
Can Yuan ◽  
Xiufen Sha ◽  
Miao Xiong ◽  
Wenjuan Zhong ◽  
Yu Wei ◽  
...  
Keyword(s):  
Plastid Genome ◽  
Species Discrimination ◽  
Chloroplast Genomes ◽  
Genomic Arrangement ◽  
Phylogenetic Implications ◽  
Solid Foundation ◽  
Conserved Gene ◽  
Fine Resolution ◽  
Genome Scale ◽  
First Time

AbstractLigusticum L., one of the largest members in Apiaceae, encompasses medicinally important plants, the taxonomic statuses of which have been proved to be difficult to resolve. In the current study, the complete chloroplast genomes of seven crucial plants of the best-known herbs in Ligusticum were presented. The seven genomes ranged from 148,275 to 148,564 bp in length with a highly conserved gene content, gene order and genomic arrangement. A shared dramatic decrease in genome size resulted from a lineage-specific inverted repeat (IR) contraction, which could potentially be a promising diagnostic character for taxonomic investigation of Ligusticum, was discovered, without affecting the synonymous rate. Although a higher variability was uncovered in hotspot divergence regions that were unevenly distributed across the chloroplast genome, a concatenated strategy for rapid species identification was proposed because separate fragments inadequately provided variation for fine resolution. Phylogenetic inference using plastid genome-scale data produced a concordant topology receiving a robust support value, which revealed that L. chuanxiong had a closer relationship with L. jeholense than L. sinense, and L. sinense cv. Fuxiong had a closer relationship to L. sinense than L. chuanxiong, for the first time. Our results not only furnish concrete evidence for clarifying Ligusticum taxonomy but also provide a solid foundation for further pharmaphylogenetic investigation.

Characterization of the complete mitochondrial genome of Notocotylus sp. (Trematoda, Notocotylidae) and its phylogenetic implications

2021 ◽  
Vol 120 (4) ◽  
pp. 1291-1301
Author(s):  
Guoliang Xu ◽  
Peng Zhu ◽  
Weining Zhu ◽  
Bo Ma ◽  
Xiaoyun Li ◽  
...  
Keyword(s):  
Mitochondrial Genome ◽  
Complete Mitochondrial Genome ◽  
Phylogenetic Implications

scholarly journals Comparative Chloroplast Genomics of Litsea Lam. (Lauraceae) and Its Phylogenetic Implications

Forests ◽  
2021 ◽  
Vol 12 (6) ◽  
pp. 744
Author(s):  
Yunyan Zhang ◽  
Yongjing Tian ◽  
David Y. P. Tng ◽  
Jingbo Zhou ◽  
Yuntian Zhang ◽  
...  
Keyword(s):  
Chloroplast Genome ◽  
Phylogenetic Analyses ◽  
Eastern China ◽  
Chloroplast Microsatellites ◽  
Endangered Tree ◽  
Protein Coding ◽  
Intergenic Spacers ◽  
Chloroplast Genomes ◽  
Phylogenetic Implications ◽  
Chloroplast Genome Sequence

Litsea Lam. is an ecological and economic important genus of the “core Lauraceae” group in the Lauraceae. The few studies to date on the comparative chloroplast genomics and phylogenomics of Litsea have been conducted as part of other studies on the Lauraceae. Here, we sequenced the whole chloroplast genome sequence of Litsea auriculata, an endangered tree endemic to eastern China, and compared this with previously published chloroplast genome sequences of 11 other Litsea species. The chloroplast genomes of the 12 Litsea species ranged from 152,132 (L. szemaois) to 154,011 bp (L. garrettii) and exhibited a typical quadripartite structure with conserved genome arrangement and content, with length variations in the inverted repeat regions (IRs). No codon usage preferences were detected within the 30 codons used in the chloroplast genomes, indicating a conserved evolution model for the genus. Ten intergenic spacers (psbE–petL, trnH–psbA, petA–psbJ, ndhF–rpl32, ycf4–cemA, rpl32–trnL, ndhG–ndhI, psbC–trnS, trnE–trnT, and psbM–trnD) and five protein coding genes (ndhD, matK, ccsA, ycf1, and ndhF) were identified as divergence hotspot regions and DNA barcodes of Litsea species. In total, 876 chloroplast microsatellites were located within the 12 chloroplast genomes. Phylogenetic analyses conducted using the 51 additional complete chloroplast genomes of “core Lauraceae” species demonstrated that the 12 Litsea species grouped into four sub-clades within the Laurus-Neolitsea clade, and that Litsea is polyphyletic and closely related to the genera Lindera and Laurus. Our phylogeny strongly supported the monophyly of the following three clades (Laurus–Neolitsea, Cinnamomum–Ocotea, and Machilus–Persea) among the above investigated “core Lauraceae” species. Overall, our study highlighted the taxonomic utility of chloroplast genomes in Litsea, and the genetic markers identified here will facilitate future studies on the evolution, conservation, population genetics, and phylogeography of L. auriculata and other Litsea species.

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