• Ocean and Polar Research
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• 제43권4호
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• pp.245-253
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• 2021

Surirella atomus Hustedt 1955, surirelloid diatom, were obtained from Hampyeong Bay, Mu-an, in the west coast of Korea. We describe the first record of S. atomus in Korea and report its ultrastructure and molecular characteristics for the first time. For molecular analysis, rbcL gene and cob gene were sequenced. This species is very small in size, making it difficult to observe its morphological features under a light microscope. Even with a scanning electron microscope, it has no unique structure in the valve. It is morphologically very simple. This rare species was known as a marine benthic species. However, it appears to be widely distributed in marine, freshwater, and brackish environments according to the literature documenting this species. In terms of phylogeny, S. atomus has been tentatively linked to Petrodictyon gemma, but the phylogenetic placement of S. atomus seems to be still uncertain, in a manner that is similar to S. febigeri. However, morphological observations derived from this study suggest that this species belongs to the genus Surirella.

• 한국패류학회지
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• 제23권2호
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• pp.155-164
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• 2007

A new species, Arca koumaci Lutaenko et Maestrati n. sp. (Bivalvia: Arcidae), is described from New Caledonia. The species is characterized by the small size, the convex shell with a strong posterior umbonal ridge covered by spikes, the widely curved ventral margin, and presence of cancellate sculpture and convergent marginal teeth. Presence of spikes on the posterior ridge is a unique morphological feature recorded for the first time in the genus. It is proposed that the only subgenus, namely Pliocene A. (Arcoptera) Heilprin, 1887, apart from nominative, can be recognized in the genus. Three morphological types are distinguished within the genus based on shell shape and sculpture. Bathymetric analysis shows that representatives of Arca inhabit water depths down to 175 m, and more than half of Recent species were found below 50 m. Types of A. bouvieri P. Fischer, 1874, Arca boucardi Jousseaume, 1894, Arca avellana Lamarck, 1819, and Arca retusa Lamarck, 1819 are illustrated.

• 식물분류학회지
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• 제37권4호
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• pp.323-333
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• 2007

The degree to which parallel evolution utilizes the same genetic mechanisms indicates the degree to which developmental processes constrain or channel phenotypic evolution. A transgenetic strategy was used to elucidate the role of one floral meristem identity gene, LEAFY (LFY), in the evolution of rosette flowering, a plant architecture that has evolved in parallel in several lineages of the mustard family, Brassicaceae. The LFY genes from three rosette flowering species were cloned and introduced into a species with the ancestral architecture, and results indicated that changes at the LFY locus contributed to the evolution of rosette flowering in two of the three lineages, but that in each lineage a different set of genetic partners was involved. Also, LFY was shown to play a role in the evolution of flower size. Transgenetic strategy may be useful in the study of plant morphological evolution and parallelism.

• ALGAE
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• 제31권2호
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• pp.105-115
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• 2016

The genus Pterosiphonia includes twenty-one currently described species of red algae that occur in temperate to tropical regions of the Atlantic and Pacific Oceans. Pterosiphonia spinifera was originally described as Polysiphonia spinifera from Peru and later transferred to Pterosiphonia. Pterosiphonia spinifera has been reported from Peru as Pterosiphonia pennata, which was originally described from the Mediterranean Sea. Recently, Pterosiphonia arenosa was described based on specimens of P. pennata from Korea. We collected P. spinifera along the coast of Peru and P. arenosa near the type locality in Korea. We compared them with the isotype specimens of P. arenosa using both morphological and molecular data. Our morphological observations and our phylogenetic analysis of rbcL sequences demonstrate that P. spinifera and P. arenosa are conspecific and indicate that P. arenosa is a later synonym of P. spinifera. Our study confirms the wide occurrence of P. spinifera in the western and eastern Pacific Ocean.

• ALGAE
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• 제28권2호
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• pp.149-160
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• 2013

Six species of the genus Symphyocladia are currently recognized worldwide, all of which are reported to grow on the Korean coast. We described a new species Symphyocladia glabra sp. nov. based on morphological and molecular evidence. The new species is characterized by mostly an erect and broad thallus, the parallel arrangement of numerous apical cells, completely fused congenital cells, a corticated basal portion of faint midrib with six to eight pericentral cells, rhizoids cutting off from pericentral cells, and absent vegetative trichoblasts. The new species has morphological similarity to S. marchantioides and S. jejuinsula. However, S. glabra sp. nov. is distinguished from S. marchantioides by the corticated lower portion of the thallus and the absence of vegetative trichoblasts, and S. jejuinsula by number of pericentral cells and the fact that the thallus does not taper upward. The phylogeny of rbcL sequences indicated that S. glabra sp. nov. is definitely a separate entity within the genus Symphyocladia.

• ALGAE
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• 제33권3호
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• pp.215-229
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• 2018

In this study, the phylogenetic relationships among the genera Alsidium C. Agardh and Bryothamnion $K{\ddot{u}}tzing$ were investigated. Phylogenetic analyses using the plastid-encoded markers rbcL, psbA, and the mitochondrial barcode region (COI-5P) resolved a well-supported clade that included the species Alsidium corallinum, Bryothamnion seaforthii, and B. triquetrum. Our results indicated that taxonomic recognition of the genus Bryothamnion is not supported and two species of Bryothamnion are reallocated to Alsidium. A reexamination of the morphological definition of Alsidium is provided with an updated diagnosis of the genus and a morphology-based comparison of species that are currently circumscribed under this generic name. Furthermore, we reviewed morphological differences and similarities between Alsidium and the genus Digenea, both belonging to the tribe Alsidieae, discussing the most relevant morphological characters.

• 식물분류학회지
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• 제49권2호
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• pp.107-117
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• 2019

Viburnum in Korea includes ten species. The phylogenetic relationships and morphology of the genus Viburnum in general have been studied substantially for the past three decades. A clear understanding of the systematic relationships and an assessment of the level of morphological variation of these plants distributed in Korea are lacking. This study investigated the morphology of these species using herbarium specimens and fresh materials obtained during fieldwork to examine the morphological variation level for a better understanding of each species in the genus. A comparative analysis showed that the species of Viburnum in Korea are easily distinguishable based on various characters of the bud, leaf, extrafloral nectary, inflorescence, corolla, fruit, and stone.

• 환경생물
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• 제41권4호
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• pp.666-676
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• 2023

Laurencia is a red algal genus that was described by J.V. Lamouroux in 1813. The main characteristics of this genus have been known as the presence of four pericentral cells in an axial segment, secondary pit connections between adjacent epidermal cells, and the presence of corps en cerise in both epidermal and trichoblast cells. Additionally, the tetrasporangia are arranged in a parallel manner, and male branches feature terminal cup-shaped spermatangial pits. Currently, sixteen Korean Laurencia species have been reported based on their morphological characteristics. In this study, Laurencia decussata and L. pacifica have been added as new records to the Korean algal flora based on a combination of morphological observations and molecular analyses of rbcL sequences. Laurencia decussata has expanded from Australia and New Zealand to Korea, while the distribution of L. pacifica has expanded from USA and Mexico to Korea.

• 식물분류학회지
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• 제37권3호
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• pp.255-273
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• 2007

한국산 노린재나무과 분류군간의 유연관계를 파악하기 위하여 전반적인 형태학적 형질의 재검토를 실시하였다. 미세형태학적 연구를 통해 잎의 표피형태, 꽃받침의 세포 침적양상, 엽병의 세포경계 및 주두의 발달정도는 종간 분류군을 구별하는 유용한 식별형질로 관찰되었다. 수리분류학적 연구 결과, 한국산 노린재나무과 4분류군은 각 분류군별로 뚜렷한 외부형태적 불연속성을 나타내어 종간의 형태적인 고유성이 인정되어 것으로 판단된다. 화분학적 결과에서는 낙엽성 분류군과 상록성 분류군의 차이점이 나타났으며 연구 결과 한국산 노린재나무과의 섬노린재, 노린재나무, 검노린재, 검은재나무 4분류군간에 명확하게 독립된 고유성을 나타내었다.

• 식물분류학회지
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• 제36권4호
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• pp.279-292
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• 2006

이 연구는 다양하게 분류되어온 한국산 엉겅퀴군(Cirsium japonicum complex)을 대상으로 주요 식별형질의 변이 양상에 대한 수리 분류학적 분석을 수행하여 그 분류군들의 한계를 규명하고자 하였다. 엉겅퀴군의 주요 식별 형질인 잎, 화서, 화관, 총포와 총포편 등 24개의 외부 형태학적 형질과 잎의 경우, 잎의 길이와 폭, 엽두와 엽저의 각, 잎의 털 밀도, 잎의 두께, 가시의 길이 등에 관한 11개의 주요 식별형질들을 측정하여 주성분 분석을 실시하였다. 그 결과, 엉겅퀴(C. japonicum var. japonicum)개체군과 가시엉겅퀴(C. japonicum var. spinosissimum) 개체군들로 구성된 2개 집단으로 구분되었으며 주요 식별 형질들의 변이 양상을 고려할 때 좁은잎엉겅퀴(C. japonicum f. nakaianum)의 변이 폭은 엉겅퀴(C. japonicum var. japonicum)의 변이 폭에 포함되었다. 그러므로 한국산 엉겅퀴군은 엉겅퀴(C. japonicum var. japonicum), 가시엉겅퀴(C. japonicum var. spinosissimum) 그리고 가시엉겅퀴의 변이 폭에 포함되지만 꽃이 흰색인 흰가시엉겅퀴(C. japonicum var. spinosissimum f. alba) 등 2변종 1품종으로 정리되었다.