• Title/Summary/Keyword: Taxonomic key

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Germ Cell Development during Spermatogenesis and Taxonomic Values of Sperm Morphology in Septifer (Mytilisepta) virgatus (Bivalvia: Mytilidae)

  • Kim, Jin-Hee;Kim, Sung-Han
    • Development and Reproduction
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    • v.15 no.3
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    • pp.239-247
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    • 2011
  • Spermatogenesis and taxonomic values of mature sperm morphology of in male Septifer (Mytilisepta) virgatus were investigated by transmission electron microscope observations. The morphologies of the sperm nucleus and the acrosome of this species are the cylinder shape and cone shape, respectively. Spermatozoa are approximately 45-50 ${\mu}m$ in length including a sperm nucleus (about 1.26 ${\mu}m$ long), an acrosome (about 0.99 ${\mu}m$ long), and tail flagellum (about 45-47 ${\mu}m$). Several electron-dense proacrosomal vesicles become later the definitive acrosomal vesicle by the fusion of several Golgi-derived vesicles. The acrosome of this species has two regions of differing electron density: there is a thin, outer electron-dense opaque region (part) at the anterior end, behind which is a thicker, more electron-lucent region (part). In genus Septifer in Mytilidae, an axial rod does not find and also a mid-central line hole does not appear in the sperm nucleus. However, in genus Mytilus in Mytilidae, in subclass Pteriomorphia, an axial rod and a mid-central line hole appeared in the sperm nucleus. These morphological differences of the acrosome and sperm nucleus between the genuses Septifer and Mytilus can be used for phylogenetic and taxonomic analyses as a taxonomic key or a significant tool. The number of mitochondria in the midpiece of the sperm of this species are five, as seen in subclass Pteriomorphia.

Taxonomic Studies on Soil Mites (Acari: Oribatei) of Korea (한국산 토양서식성응애(응애목: 날개응애아목)의 분류에 관한 연구)

  • 최성직
    • Korean journal of applied entomology
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    • v.33 no.1
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    • pp.39-50
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    • 1994
  • In the course of the taxonomic study on onbatid mites from Korea, the author obtained one nau genus, 5 new species, 1 new subspecies, and 5 species unrecorded in Korea for th first time. They are Koreonbates foliatus gen. n, sp. n., Hermannio neotricha sp. n., Xyiobates geonjiensis sp. n., Defectamems sungohi sp. n., Protoripoda flagellato sp. n., Liocarus gommatus coreanus ssp. n., Liocarus polychoihomus Wen, 1991, Tectodamoeus armatus Aok, 1984, T striatus Enami et Aoki, 1988. Oripoda trilabiata Hammer, 1961, and Dometorino tuberculata Aoki, 1984. And keys to the species and subspec~es of genera Liacorus, Defectamems, and Protoripoda are present All the specimens are deposited at the Lab of Plant Protection, Coli, ot Agr, Won Kwang Univ., hi, Korea. KEY WORDS Taxonomic, Acari, Oribatei, Korea.

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The Report on the Taxonomic Characters, Ecological Risk and Weed Risk Assessment of Putative Invasive Alien Plants which are Designated in Law by the Ministry of Environment in Korea as Environmentally Harmful Species (III)

  • Kim, Tae-Hee;Yoon, ChangYoung;Kim, Joo-Hwan
    • Korean Journal of Plant Resources
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    • v.34 no.3
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    • pp.223-248
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    • 2021
  • We conducted a taxonomic study and agricultural environmental risk assessments of 41 putative invasive alien plants designated by the Ministry of Environment in 2016. In order to achieve the goal, we carried out the field survey four times including the United States, Australia, and Mexico, and investigated specimens, literature, and other information including seed morphology, classification key, and habitat conditions. In this study, we reported the taxonomic characters, ecological risk, and weed risk assessment of 41 putative invasive alien plants, and suggested significant information about 11 species to contribute to establish solutions of regulation management for putative invasive alien plants - Spirodela punctata (G.Mey.) C.H.Thomps. (Araceae), Sagittaria graminea Michx. (Alismataceae), Elodea nuttallii (Planch.) H.St. John, Hydrocharis morsus-ranae L., Stratiotes aloides L. (Hydrocharitaceae), Eichhornia azurea (Swartz) Kunth, Monochoria hastata (L.) Solms (Pontederiaceae), Aegilops tauschii Coss. (Poaceae), Myriophyllum heterophyllum Michx. (Haloragaceae), Bunias orientalis L. (Brassicaceae), and Heracleum sosnowskyi Manden. (Apiaceae).

Description of two new species from South Korea and Russian Far East with a key to the Palearctic species of the genus Brachyserphus Helle´n (Hymenoptera, Proctotrupidae)

  • Choi, Moon-Bo;Kolyada, Victor A.;Lee, Jong-Wook
    • Animal cells and systems
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    • v.16 no.3
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    • pp.237-244
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    • 2012
  • A taxonomic study of the Palearctic species of the genus Brachyserphus is presented. Two species are newly described as B. acuticaudatus sp. n. and B. semipunctatus sp. n. from South Korea and the Russian Far East. B. striatopropodeatus (Kolyada 1997 syn. n.) is synonymized under B. lucens (Provancher 1883) and a key to the Palearctic species is provided.

Taxonomic Review of the Tribe Campsomerini (Scoliinae, Scoliidae, Hymenoptera) in Korea

  • Kim, Jeong-Kyu
    • Animal Systematics, Evolution and Diversity
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    • v.25 no.1
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    • pp.99-106
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    • 2009
  • Six Korean species of the tribe Campsomerini are taxonomically reviewed: Campsomeriella annulata, Megacampsomeris grossa matsumurai, M. prismatica, M. uchidai, M. schulthessi, M. stoetzneri. Of these, M. grossa matsumurai and M. stoetzneri are new to Korea. A key to Korean genera and species, diagnostic characteristics and digital images are also provided.

Germ Cell Development During Spermatogenesis and Some Characteristics of Mature Sperm Morphology in Male Scapharca subcrenata (Pteriomorphia: Arcidae) in Western Korea

  • Chung, Ee-Yung;Kim, Jin-Hee;Kim, Sung-Han;Seo, Won-Jae
    • The Korean Journal of Malacology
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    • v.27 no.2
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    • pp.121-129
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    • 2011
  • The ultrastructural characteristics of germ cell development during spermatogenesis and mature sperm morphology of in male Scapharca subcrenata were investigated by transmission electron microscope observation. Spermatogonia are located nearest the outer wall of the acinus, while spermatocytes and spermatids are positioned near the accessory cells. The accessory cells, which is in close contact with developing germ cells, contained a large quantity of glycogen particles and lipid droplets in the cytoplasm. Therefore, it is assumed that they are involved in supplying of the nutrients for germ cell development. The morphologies of the sperm nucleus and the acrosome of this species are the oval shape and cone shape, respectively. Spermatozoa are approximately 45-$50{\mu}m$ in length including a sperm nucleus (about $1.30{\mu}m$ in length), an acrosome (about $0.59{\mu}m$ in length), and tail flagellum (about 43-$47{\mu}m$). The axoneme of the sperm tail shows a 9 + 2 structure. As some characteristics of the acrosomal vesicle structures, the right and left basal rings show electron opaque part (region), and also the anterior apex part of the acrosomal vesicle shows electron opaque part (region). These characteristics of the acrosomal vesicle were found in Acinidae and other several families in subclass Pteriomorphia. These common characteristics of the acrosomal vesicle in subclass Pteriomorphia can be used for phylogenetic and taxonomic analysis as a taxonomic key or a significant tool. The number of mitochondria in the midpiece of the sperm of this species are five, as one of common characteristics appear in most species in Arcidae and other families in subclass Pteriomorphia. The acrosomal vesicles of Arcidae species do not contain the axial rod and several transverse bands in acrosome, unlkely as seen in Ostreidae species in subclass Pteriomorphia, These characteristics can be used for the taxonomic analysis of the family or superfamily levels as a systematic key or tools.

Characterization of microbiota diversity of engorged ticks collected from dogs in China

  • Wang, Seongjin;Hua, Xiuguo;Cui, Li
    • Journal of Veterinary Science
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    • v.22 no.3
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    • pp.37.1-37.14
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    • 2021
  • Background: Ticks are one of the most common external parasites in dogs, and are associated with the transmission of a number of major zoonoses, which result in serious harm to human health and even death. Also, the increasing number of pet dogs and pet owners in China has caused concern regarding human tick-borne illnesses. Accordingly, studies are needed to gain a complete understanding of the bacterial composition and diversity of the ticks that parasitize dogs. Objectives: To date, there have been relatively few reports on the analysis of the bacterial community structure and diversity in ticks that parasitize dogs. The objective of this study was to investigate the microbial composition and diversity of parasitic ticks of dogs, and assessed the effect of tick sex and geographical region on the bacterial composition in two tick genera collected from dogs in China. Methods: A total of 178 whole ticks were subjected to a 16S ribosomal RNA (rRNA) next generation sequencing analysis. The Illumina MiSeq platform targeting the V3-V4 region of the 16S rRNA gene was used to characterize the bacterial communities of the collected ticks. Sequence analysis and taxonomic assignment were performed using QIIME 2 and the GreenGene database, respectively. After clustering the sequences into taxonomic units, the sequences were quality-filtered and rarefied. Results: After pooling 24 tick samples, we identified a total of 2,081 operational taxonomic units, which were assigned to 23 phyla and 328 genera, revealing a diverse bacterial community profile. The high, moderate and low prevalent taxa include 46, 101, and 182 genera, respectively. Among them, dominant taxa include environmental bacterial genera, such as Psychrobacter and Burkholderia. Additionally, some known tick-associated endosymbionts were also detected, including Coxiella, Rickettsia, and Ricketssiella. Also, the potentially pathogenic genera Staphylococcus and Pseudomonas were detected in the tick pools. Moreover, our preliminary study found that the differences in microbial communities are more dependent on the sampling location than tick sex in the tick specimens collected from dogs. Conclusions: The findings of this study support the need for future research on the microbial population present in ticks collected from dogs in China.

Taxonomic Study of the Genus Pholiota (Strophariaceae, Basidiomycota) in Korea

  • Lee, Jun Won;Park, Myung Soo;Park, Ji-Hyun;Cho, Yoonhee;Kim, Changmu;Kim, Chang Sun;Jo, Jong Won;Lim, Young Woon
    • Mycobiology
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    • v.48 no.6
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    • pp.476-483
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    • 2020
  • The genus Pholiota (Strophariaceae, Basidiomycota) is made up of wood-rotting saprotrophic mushrooms characterized by a yellow or brown pileus with scales and/or slimy, and by a brownish smooth spore with a germ pore. However, these features are not enough to distinguish its species, or separate the genus Pholiota from other brown-spored wood-rotting genera such as Hypholoma and Stropharia. Although internal transcribed spacer (ITS) sequencebased identification has improved identification accuracy for species of Pholiota, most Pholiota species in Korea are reported based on morphological features. To evaluate the taxonomy of Pholiota species, we investigated 62 specimens collected from 1999 to 2019 in Korea using ITS sequence analysis and morphological observation. Twelve of the 16 recorded Pholiota species in Korea were identified. While eight species were clearly separated, the ITS analysis did not distinguish three in the Pholiota adiposa complex. Therefore, further investigation is required to distinguish these three species. ITS sequences deposited in GenBank confirm that P. highlandensis exists in Korea. The presence of the other four Pholiota species could not be confirmed through specimens or sequence information in GenBank. A taxonomic key and the ITS sequence data for Korean Pholiota species are included and can be good baselines for further research on Pholiota taxonomy and diversity.