Article
Plant Sciences
So Young Jeong, Guillermo Diaz-Pulido, Gavin W. Maneveldt, Paul W. Gabrielson, Wendy A. Nelson, Boo Yeon Won, Tae Oh Cho
Summary: A multigene molecular phylogeny was conducted to study the genus Phymatolithon. The study revealed the polyphyletic grouping of two monophyletic clades within the Hapalidiales. As a result, a new genus, Phymatolithopsis, was established, consisting of three species. Phymatolithopsis is closely related to Mesophyllum and is distinct from Phymatolithon and boreal species assigned to Lithothamnion. Morpho-anatomical characteristics were used to differentiate Phymatolithopsis from Phymatolithon, including the origin of conceptacle primordia and the distribution of gonimoblast filaments in carposporangial conceptacles.
JOURNAL OF PHYCOLOGY
(2022)
Article
Plant Sciences
Cibele Conceicao dos Santos, Jose Marcos de Castro Nunes, Gabriel do Nascimento Santos, Edilene Maria dos Santos Pestana, Valeria Cassano, Goia de Mattos Lyra
Summary: This study conducted molecular, genetic, and morphological analyses of Lomentariaceae, resulting in the discovery of a new species, Ceratodictyon sanctae-crucis sp. nov., and the proposal of a new genus, Yendoa gen. nov., within Lomentariaceae. The study also revealed that Lomentariaceae now consists only of monophyletic genera, providing a more coherent taxonomic framework for the family.
Article
Limnology
Kunpeng Fang, Fangru Nan, Jia Feng, Junping Lu, Qi Liu, Xudong Liu, Shulian Xie
Summary: This study describes a new genus and species of freshwater red alga called Pauciramus yunnanensis. Based on morphological characteristics and phylogenetic analysis, a new order called Ottiales is proposed, which includes the genera Ottia and Pauciramus. The findings suggest a close relationship between Pauciramus and Ottia, and they are classified within the family Ottiaceae.
JOURNAL OF OCEANOLOGY AND LIMNOLOGY
(2022)
Article
Plant Sciences
Carlos Frederico D. Gurgel, Luanda P. Soares, James N. Norris, Mutue T. Fujii, William E. Schmidt, Suzanne Fredericq
Summary: This study focuses on the marine red algal family Gracilariaceae, specifically investigating Hydropuntia and Crassiphycus. It identified potentially undescribed species, showed strong phylogeographic patterns, and helped redefine morphologically similar taxa. Additionally, a time-calibrated phylogeny for the six genera in the Gracilariales was provided to understand their origin and diversification.
EUROPEAN JOURNAL OF PHYCOLOGY
(2021)
Article
Plant Sciences
Riccardo Trentin, Emanuela Moschin, Alessandro Grapputo, Fabio Rindi, Stefano Schiaparelli, Isabella Moro
Summary: During the XXVIII Italian Expedition to Antarctica in 2013, non-geniculate coralline algal specimens were collected in Adelie Cove and deposited in the collections of the Italian National Antarctic Museum. Through a combination of DNA sequence data and morpho-anatomical observations, the specimens were characterized and identified as a new species, which belongs to the order Hapalidiales but is distinct from any known genus in this order. A new genus, Thalassolithon gen. nov., is proposed for this newly discovered species, named T. adeliense sp. nov.
Article
Anatomy & Morphology
Leonardo Kerber, Agustin G. Martinelli, Rodrigo T. Muller, Flavio A. Pretto
Summary: Irajatherium hernandezi is a poorly known non-mammaliaform cynodont from the Late Triassic of southern Brazil. A new specimen of this cynodont was found, providing new insights into its anatomy such as the broad and short rostrum, divided cerebral hemispheres, and unresolved relationships in the phylogenetic analysis. Additionally, it was suggested that I. hernandezi presents unique features like a wide temporal fossa and long secondary palate.
ANATOMICAL RECORD-ADVANCES IN INTEGRATIVE ANATOMY AND EVOLUTIONARY BIOLOGY
(2022)
Article
Paleontology
Olivier Bethoux, Lea Grauvogel-Stamm
Summary: The article describes a new species of stem-Orthoptera and highlights its unique characteristics compared to known species. This discovery adds to our understanding of the differentiation of stem-groups within the Orthoptera order.
Article
Marine & Freshwater Biology
Amal Hajiya Hasan, Pierrot Van der Aa, Frithjof C. Kupper, Dhia Al-Bader, Akira F. Peters
Summary: A new filamentous marine red alga, Kuwaitiella rubra gen. et sp. nov., is described from Kuwait. It has unique morphological and genetic characteristics, different from other species of the genus Bangiales.
PHYCOLOGICAL RESEARCH
(2022)
Article
Plant Sciences
Nicolas Chomerat, Maria Saburova, Gwenael Bilien, Frederic Zentz, Mona Hoppenrath
Summary: A new thecate, photosynthetic, sand-dwelling marine dinoflagellate, Coutea sabulosa gen. & sp. nov., was discovered in various locations. It has oval cells, small size, and a conspicuous apical hook projection pointing to the right.
Article
Zoology
C. Gebicki, D. Swierczewski, M. Zmarzly, M. Walczak
Summary: This article describes a new species found in Baltic amber, belonging to the extinct tribe Protodikraneurini. This tribe is considered a distinctive element in the amber forest ecosystems.
EUROPEAN ZOOLOGICAL JOURNAL
(2023)
Article
Plant Sciences
Katia Sciuto, Emanuela Moschin, Giuseppina Alongi, Matteo Cecchetto, Stefano Schiaparelli, Annalisa Caragnano, Fabio Rindi, Isabella Moro
Summary: Advancements in our understanding of coralline algae diversity have been made with the use of DNA sequence data, revealing a potential underestimation of diversity in Antarctica. The discovery of a new genus, Tethysphytum, highlights the importance of molecular data in future taxonomic assessments within this region.
EUROPEAN JOURNAL OF PHYCOLOGY
(2021)
Article
Plant Sciences
Richard Dumilag, Giuseppe C. Zuccarello
Summary: This study investigated the genetic variation and species relationships of Mimica arnoldii, a member of the Eucheumatoids genus, as well as whether its two distinct morphological expressions have genetic differences. The results showed that Mimica is a distinct genus and that the molecular data did not correspond to the morphology-based varieties.
Article
Ecology
Kohei Takahashi, Hiroko Kawai-Toyooka, Ryo Ootsuki, Takashi Hamaji, Yuki Tsuchikane, Hiroyuki Sekimoto, Tetsuya Higashiyama, Hisayoshi Nozaki
Summary: The study revealed a new haploid mating system in Pleodorina starrii with three sex phenotypes: male, female, and bisexual. Genetic analyses suggested the presence of a autosomal bisexual factor locus independent of volvocine male and female determining regions, providing insight into the initial evolutionary step from heterothallism to homothallism. The findings indicated that the strains belong to the same biological species, with intercrossings demonstrating normal zygote formation and high survivability of F1 strains.
Article
Plant Sciences
Tomomi Nakashima, Jun Uetake, Takahiro Segawa, Lenka Prochazkova, Akane Tsushima, Nozomu Takeuchi
Summary: Snow algae are photosynthetic microbes found in melting snow in alpine and polar regions. Analysis of pigments and species composition in colored snow from Mt. Tateyama in Japan revealed four main types, with Sanguina algae dominant in producing astaxanthin-rich red snow. The study also showed that different algae species, such as Chloromonas or Chlainomonas, can lead to varying pigment compositions in colored snow.
FRONTIERS IN PLANT SCIENCE
(2021)
Article
Multidisciplinary Sciences
Takahiro Segawa, Takahiro Yonezawa, Hiroshi Mori, Ayumi Akiyoshi, Morten E. Allentoft, Ayako Kohno, Fuyuki Tokanai, Eske Willerslev, Naoki Kohno, Hidenori Nishihara
Summary: The biogeography of brown bears in the Japanese Archipelago was significantly affected by sea-level fluctuations, with evidence showing at least two migration events from the Eurasian continent to Honshu. Glacial-age sea-level falls may have facilitated mammalian migrations more frequently than previously thought, impacting ecosystem dynamics on these isolated islands.
ROYAL SOCIETY OPEN SCIENCE
(2021)
Article
Cell Biology
Naoki Oishi, Takahiro Segawa, Kunio Miyake, Kunio Mochizuki, Tetsuo Kondo
Summary: This study aimed to investigate the incidence and clinicopathological characteristics of ISFNs in the Japanese population. The findings showed that the incidence of isolated ISFN in Japan is similar to that in Europe, and these incidentally found ISFNs have a low potential to transform into overt FL. Further molecular studies are needed to identify driver genes leading to the transformation of ISFN to overt FL.
Article
Plant Sciences
Hisayoshi Nozaki, Wuttipong Mahakham, Wirawan Heman, Ryo Matsuzaki, Masanobu Kawachi
Summary: The study reveals the high diversity in mating systems of Volvox africanus, with the third mating system potentially representing an evolutionary transition from heterothallism to homothallism. Further research in stable intracontinental regions could contribute to the understanding of diversity and taxonomy of the freshwater green algal genus Volvox.
Article
Biochemistry & Molecular Biology
Takahiro Segawa, Takahiro Yonezawa, Hiroshi Mori, Ayako Kohno, Yuichiro Kudo, Ayumi Akiyoshi, Jiaqi Wu, Fuyuki Tokanai, Minoru Sakamoto, Naoki Kohno, Hidenori Nishihara
Summary: This study reveals the genetic origin of Japanese wolves by analyzing ancient DNA. The findings show that the Pleistocene wolf was not a subspecies of the Japanese wolf, but belonged to an earlier-diverging lineage, while the Holocene Japanese wolf was a mixture of the Japanese Pleistocene wolf and continental wolf lineages.
Article
Plant Sciences
Tomoyuki Takano, Hisato Ikegaya, Kenichi Ikeda, Hisayoshi Nozaki, Hidetoshi Sakayama
Summary: Characteristics of transverse walls and modes of conjugation are crucial for species identification in the genus Spirogyra. This study examined two Spirogyra species with different types of transverse walls collected in Japan and found their distinct vegetative and reproductive traits. Molecular phylogenetic analyses also revealed their separate lineages in the tree of Spirogyra species. The two Japanese strains are described as new species, S. minuticrassispina sp. nov. and S. tertia sp. nov.
Article
Engineering, Environmental
Mayumi Kobayashi, Qian Zhang, Takahiro Segawa, Mitsuto Maeda, Reiko Hirano, Satoshi Okabe, Satoshi Ishii
Summary: Migratory geese can have significant impacts on water quality and public health by affecting the microbiological composition and nutrient levels in freshwater lakes. They are likely to be a major source of Campylobacter bacteria in the lake, while the occurrence of Arcobacter group bacteria is not directly related to the presence of geese. The nutrient inputs provided by geese can lead to eutrophication and lower dissolved oxygen concentrations, indirectly impacting the indigenous microbial population of the lake.
Article
Microbiology
Takumi Murakami, Nozomu Takeuchi, Hiroshi Mori, Yuu Hirose, Arwyn Edwards, Tristram Irvine-Fynn, Zhongqin Li, Satoshi Ishii, Takahiro Segawa
Summary: This study provided the first characterization of the taxonomic and metabolic diversities of cryoconite from different geographical areas. It was found that cryoconite bacterial communities in Asia and Polar regions show distinct compositions and metabolic characteristics, indicating the influence of environmental factors on the assemblage of cryoconite communities.
Article
Ecology
Takahiro Segawa, Takahiro Yonezawa, Ryo Matsuzaki, Hiroshi Mori, Ayumi Akiyoshi, Francisco Navarro, Koji Fujita, Vladimir B. B. Aizen, Zhongqin Li, Shuhei Mano, Nozomu Takeuchi
Summary: Recent studies have found that cosmopolitan phylotypes of snow algae were persistently present long before the last glacial period, and endemic phylotypes originated from ancestral cosmopolitan phylotypes. These findings suggest that cosmopolitans dispersed across the world and then derived new localized endemics, revealing the role of microevolution in microbial community formation in natural environments.
Article
Multidisciplinary Sciences
Youichi Shinozaki, Alex Leung, Kazuhiko Namekata, Sei Saitoh, Huy Bang Nguyen, Akiko Takeda, Yosuke Danjo, Yosuke M. Morizawa, Eiji Shigetomi, Fumikazu Sano, Nozomu Yoshioka, Hirohide Takebayashi, Nobuhiko Ohno, Takahiro Segawa, Kunio Miyake, Kenji Kashiwagi, Takayuki Harada, Shin-ichi Ohnuma, Schuichi Koizumi
Summary: Loss of ABCA1 in retinal astrocytes causes glaucoma-like optic neuropathy in aged mice, leading to retinal ganglion cell degeneration and ocular dysfunction.
Article
Biology
Shoichi Kato, Osami Misumi, Shinichiro Maruyama, Hisayoshi Nozaki, Yayoi Tsujimoto-Inui, Mari Takusagawa, Shigekatsu Suzuki, Keiko Kuwata, Saki Noda, Nanami Ito, Yoji Okabe, Takuya Sakamoto, Fumi Yagisawa, Tomoko M. M. Matsunaga, Yoshikatsu Matsubayashi, Haruyo Yamaguchi, Masanobu Kawachi, Haruko Kuroiwa, Tsuneyoshi Kuroiwa, Sachihiro Matsunaga
Summary: Multi-omic and evolutionary analyses of the ultrasmall green alga, Medakomo hakoo, suggest it belongs to a new genus within the class Trebouxiophyceae and provide insight into essential genes for microalgae. With a genome size of 15.8 Mbp and 7629 genes, it is among the smallest genomes in the Viridiplantae. Comparative analyses reveal shared gene sets among 15 ultrasmall algae, enabling identification of essential genes for metabolism and cellular functions.
COMMUNICATIONS BIOLOGY
(2023)
Article
Multidisciplinary Sciences
Kayoko Yamamoto, Ryo Matsuzaki, Wuttipong Mahakham, Wirawan Heman, Hiroyuki Sekimoto, Masanobu Kawachi, Yohei Minakuchi, Atsushi Toyoda, Hisayoshi Nozaki
Summary: By comparing genome data from Thai and Japanese genotypes of the homothallic green alga Volvox africanus, it was found that expanded ancestral male and female sex-determining regions (SDRs) may have originated from an ancient heterothallic ancestor and were conserved during the evolution of homothallic genotypes. An expanded SDR-like region appears to be essential for homothallic sexual reproduction in V. africanus, regardless of its male or female origin. This study highlights the future possibility of elucidating the biological significance of these expanded genomic regions.
Article
Biology
Kohei Takahashi, Shigekatsu Suzuki, Hiroko Kawai-Toyooka, Kayoko Yamamoto, Takashi Hamaji, Ryo Ootsuki, Haruyo Yamaguchi, Masanobu Kawachi, Tetsuya Higashiyama, Hisayoshi Nozaki
Summary: The coexistence of three sexual phenotypes (male, female and bisexual) in a single species, 'trioecy', has been observed in a green algal species, P. starrii, due to the reorganization of ancestral sex chromosomes.
COMMUNICATIONS BIOLOGY
(2023)
Article
Ecology
Ryo Matsuzaki, Shigekatsu Suzuki, Haruyo Yamaguchi, Masanobu Kawachi, Yu Kanesaki, Hirofumi Yoshikawa, Toshiyuki Mori, Hisayoshi Nozaki
Summary: The study suggests that the hydrophobicity of RBCS helices is roughly correlated with the presence or absence of pyrenoids within the Reticulata group, and a decrease in hydrophobicity of RBCS helices may have primarily caused pyrenoid loss during the evolution of this group. This provides novel insight into a potential mechanism determining initial evolutionary steps of gain and loss of the pyrenoid.
BMC ECOLOGY AND EVOLUTION
(2021)
