• Korean Journal of Plant Taxonomy
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• v.44 no.1
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• pp.22-32
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• 2014

The petal and sepal micromorphology of five species of Glechoma (Lamiaceae) was investigated to evaluate their taxonomic significance, and a molecular phylogeny using the sequences of internal transcribed spacers (ITS) regions of nuclear ribosomal DNA was carried out to resolve their phylogenetic relationships. Stomatal complexes were mostly found in the inner and outer part of the sepal from all investigated taxa, and the size length of the guard cell was variable among the taxa. Five types of trichomes (uni-cellular non-glandular trichome, multi-cellular non-glandular trichome, short-stalked capitate glandular trichome, long-stalked capitate glandular trichome, and peltate glandular trichome) were variable among the taxa as well as their distribution and density. In molecular phylogenetic studies, the genus Glechoma was composed of three geographically distinct major monophyletic groups (Europe-U.S.A., China-Korea, Japan). G. longituba in Korea and China formed well-supported monophyletic group. G. hederacea in Europe and U.S.A. formed a monophyletic and well-supported clade with G. sardoa, which are endemic species in Italy, with G. hirsuta falling as a sister to this clade. However, G. grandis did not form any phylogenetic relationships with the remaining taxa. The ITS analyses provided taxonomic boundaries of taxa in Glechoma although the petal and sepal micromorphological characters provided weak evidences of the systematic value. As further studies, incorporating more DNA regions to the matrix including other additional morphological analysis will be significant to provide clearer taxonomic structure in Glechoma.

• Korean Journal of Plant Taxonomy
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• v.37 no.3
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• pp.239-254
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• 2007

A comparative micromorphological study was examined on the leaves of the genus Glechoma and related genera (Nepetinae, Lamiaceae) by scanning electron microscopy (SEM) in order to evaluate their significance in the taxonomy. The leaves of taxa Marmoritis, Nepeta sect. Glechomanthe, G. hederacea var. longituba (Korea) are revealed amphistomatic type, while the remnants of taxa had hypostomatic type. The size range of the guard cells is $12.50-28.75{\times}9.17-21.25{\mu}m$: the smallest one was found in M. pharicus ($12.50-15.83{\times}9.17-11.25{\mu}m$), while the largest one was measured to G. hederacea var. longituba (Korea: $28.75-28.88{\times}21.25-21.38{\mu}m$). The stomatal type of genera Agastache, Dracocephalum was mostly diacytic, however for the rest rarely together with anisocytic and anomocytic, except G. hederaca var. longituba (Korea), Meehania urticifolia by having combined with diacytic and anomocytic. The shapes of epidermal cells are differ from in abaxial and adaxial side, and dived with two types (e.g., platelet, stripe pattern). Five types (three glandular, two non-glandular hairs) of trichomes are distributed in leaves. Among trichomes, long and stalk capitates glandular trichome, subsessile glands are different from studied taxa so that leaf micromorphological characters are significance features in the taxonomy.

• Korean Journal of Plant Taxonomy
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• v.40 no.1
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• pp.50-58
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• 2010

The nutlet morphology and pericarp structure of 14 taxa (4 taxa of the genus Glechoma and related taxa) were studied by light and scanning electron microscopy, and a detailed description of nutlet morphological features for all examined taxa is provided. The shape of the nutlet is ovate to elliptic. Its size is 1.36-3.83 mm in length and 0.80-2.65 mm in width. The largest one was found in Marmoritis rotundifolia, while the smallest one was in Agastache nepetoides. Three different surface types were recognized in the studied taxa based on differences in cell outline and cell boundary relief (rectangular, pitted, and ridged negative reticulate-cell). Three types of trichome (uni-cellular non-glandular trichome, multi-cellular non-glandular trichome, and peltate glandular trichome) were distributed in the nutlets. The pericarp is formed in three layers (i.e., exocarp, mesocarp, and endocarp including sclenchyma tissue), and the pericarp in the studied species is $39.0-237.5{\mu}m$ thick. The morphological and anatomical features (the nutlet shape, surface type, and trichome distribution) in the genus Glechoma and related taxa are described and discussed.