• Title/Summary/Keyword: genus two

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Trichome Morphology of Cimicifuga L. (Ranunculaceae) and Its Taxonomic Significance

  • Park, Chong-Wook
    • Journal of Plant Biology
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    • v.38 no.3
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    • pp.289-295
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    • 1995
  • Trichomes found in the genus Cimicifuga were examined with scanning electron microscopy. Four basic types of trichomes were found in the genus; (1) filiform unicellular trichomes, (2) saccate unicellular trichomes, (3) pyriform unicellular trichomes, and (4) uniseriate multicellular trichomes. All the taxa examined develop at least two different types of trichomes, and many taxa are distinguished by differences in type, microornamentation, density, and position of trichomes. In addition, trichome features appear to be very useful in recognizing species relationships in the genus.

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A Redescription of Sciasmomyia supraorientalis (Insecta: Diptera: Lauxaniidae), the First Recorded Genus and Species in Korea

  • Lee, Hyun-Suk;Han, Ho-Yeon
    • Animal Systematics, Evolution and Diversity
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    • v.25 no.2
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    • pp.209-213
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    • 2009
  • The genus Sciasmomyia (Diptera: Lauxaniidae) was discovered for the first time in Korea. This Old World (PA and OR) genus currently includes two nominal species. In the process of revising Korean Lauxaniidae, we were able to collect Korean representatives of Sciasmomyia supraorientalis, and provide the redescriptions and illustrations of both sexes.

Molecular phylogeny of Astilbe: Implications for phylogeography and morphological evolution (노루오줌속(Astilbe)의 분자 계통: 계통지리 및 형질 진화에 대한 고찰)

  • Kim, Sang-Yong;Kim, Sung-Hee;Shin, Hyunchur;Kim, Young-Dong
    • Korean Journal of Plant Taxonomy
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    • v.39 no.1
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    • pp.35-41
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    • 2009
  • Astilbe (Saxifragaceae) is a genus well known for its disjunctive distribution in Asia and eastern North America. In this study, we reconstructed a molecular phylogeny of the genus using the sequences of ITS regions of nuclear ribosomal DNA. A total of 17 species representing major lineage of Astilbe and closely related taxa were included in the phylogenetic analyses. We obtained a Bayesian phylogenetic tree in which Saxifragopsis was positioned as a sister group to Astilbe. The Japanese endemic species, A.platyphylla was the most basal lineage within the genus. This species is well known for its distinct morphological features such as unisexual flowers, apetaly, and calyx with 7-11 lobes. Two species, A. biternata, a New World representative of the genus, and A. rivularis widely distributed in S. Asia, branched off early in the evolution of Astilbe. The remaining species formed a strongly supported core clade, which diverged into two robust geographical lineages: the first ("Japonica" clade) of species distributed in Japan, Taiwan, and Philippines and the other ("Rubra" clade), of taxa in China and Korea. The ITS phylogeny indicates that the Bering land bridges were the major route for the origin and dispersal of A. biternata. The two Taiwanese taxa and A. philippinensis were found to derive from the Japanese member, as the genus advanced southwards. The ITS phylogeny suggests that apetaly originated independently at least two times within the genus. Our results do not support Engler's classification system of the genus based on the leaf type (simple vs. compound), but reaffirm Hara's taxonomic idea which primarily considered the features of calyx.

Polyphasic delimitation of a filamentous marine genus, Capillus gen. nov. (Cyanobacteria, Oscillatoriaceae) with the description of two Brazilian species

  • Caires, Taiara A.;Lyra, Goia de M.;Hentschke, Guilherme S.;da Silva, Aaron Matheus S.;de Araujo, Valter L.;Sant'Anna, Celia L.;Nunes, Jose Marcos de C.
    • ALGAE
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    • v.33 no.4
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    • pp.291-304
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    • 2018
  • Lyngbya C. Agardh ex Gomont is a nonheterocytous cyanobacterial genus whose evolutionary history is still poorly known. The traditionally defined Lyngbya has been demonstrated to be polyphyletic, including at least five distinct clades, some of which have been proposed as new genera. Intraspecific diversity is also clearly underestimated in Lyngbya due to the lack of unique morphological characters to differentiate species. In this study, we describe the new genus Capillus T. A. Caires, C. L. Sant'Anna et J. M. C. Nunes from benthic marine environments, including two new Brazilian species (here described as C. salinus T. A. Caires, C. L. Sant'Anna et J. M. C. Nunes, and C. tropicalis T. A. Caires, C. L. Sant'Anna et J. M. C. Nunes), and two species yet to be described, one of them from India (Capillus sp. 2.1), and the other from United States of America, based on strain PCC 7419. Capillus species presented cross-wise diagonal fragmentation, assisted or not by necridic cells, which has not been previously mentioned for Lyngbya. Ultrastructural analyses showed that C. salinus and C. tropicalis have numerous gas vesicles, which are rarely described for benthic marine species. The new genus formed a well-supported clade, and the D1-D1' and Box B secondary structures of internal transcribed spacer also supported the proposal of its new species. These findings help to clarify the diversity of species in the Lyngbya complex and the taxonomy of the group, and highlight the need of further floristic surveys in tropical coastal environments, which remain poorly studied.

Two New Species of the Genus Mycale(Poecilosclerida: Mycalidae) from Korea

  • Sim, Chung Ja;Lee, Kyung Jin
    • Animal cells and systems
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    • v.5 no.1
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    • pp.25-29
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    • 2001
  • Two new species belonging to genus Mycale are described from the waters around Geojedo Island and Gageodo Island, Korea. Mycale (M.) geojensis n. sp. seems close to M. (M.) adhaerens parvasigma Hoshino, 1981, but our new species has three categories of anisochelae. M. (Aegogropila) hentscheli n. sp. is closest to M. (A.) obscura (Carter, 1882) in shape and spicule, but has no large sigma.

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STRUCTURES OF GEOMETRIC QUOTIENT ORBIFOLDS OF THREE-DIMENSIONAL G-MANIFOLDS OF GENUS TWO

  • Kim, Jung-Soo
    • Journal of the Korean Mathematical Society
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    • v.46 no.4
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    • pp.859-893
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    • 2009
  • In this article, we will characterize structures of geometric quotient orbifolds of G-manifold of genus two where G is a finite group of orientation preserving diffeomorphisms using the idea of handlebody orbifolds. By using the characterization, we will deduce the candidates of possible non-hyperbolic geometric quotient orbifolds case by case using W. Dunbar's work. In addition, if the G-manifold is compact, closed and the quotient orbifold's geometry is hyperbolic then we can show that the fundamental group of the quotient orbifold cannot be in the class D.