• Title/Summary/Keyword: taxonomic relationships

Search Result 141, Processing Time 0.023 seconds

Ultrastructure of the flagellar apparatus in cryptomorphic Cryptomonas curvata (Cryptophyceae) with an emphasis on taxonomic and phylogenetic implications

  • Nam, Seung Won;Shin, Woongghi
    • ALGAE
    • /
    • v.31 no.2
    • /
    • pp.117-128
    • /
    • 2016
  • Cryptomonas curvata Ehrenberg is a photosynthetic freshwater flagellate and the type species of the genus Cryptomonas. We examined the flagellar apparatus of cryptomorphic C. curvata by transmission electron microscopy. The major components of the flagellar apparatus are the non-keeled rhizostyle (Rhs), striated fibrous root (SR), striated fiber-associated microtubular root (SRm), mitochondrion-associated lamella (ML), and two types of microtubular roots (3r and 2r). The non-keeled Rhs originate at the ventral basal body and consist of two types of microtubule bands extending together into the middle of the cell. The SR and SRm extend parallel to the left side of the cell. The ML originates from the ventral basal body and is a plate-like fibrous structure associated with mitochondria. The 3r extends from the dorsal basal body toward the dorsal anterior of the cell. The 2r originates between the two basal bodies and extends shortly to the left of the cell. The overall configuration of the flagellar apparatus is most similar to that previously reported for C. pyrenoidifera. These results demonstrate that the features of the flagellar apparatus are useful for distinguishing closely related species and inferring phylogenetic relationships among taxa.

Morphology and Ecological Notes on the Larvae and Pupae of Simulium (Simulium) from Korea

  • Kim, Sam-Kyu
    • Animal Systematics, Evolution and Diversity
    • /
    • v.31 no.4
    • /
    • pp.209-246
    • /
    • 2015
  • Morphological features of larvae and pupae of twelve species of Simulium (Simulium) from Korea are investigated and redescribed. Detailed descriptions of immature stages of each species are provided with photographs. For the Korean members of subgenus Simulium, combinations of the following characteristics can be used to separate them from other Korean subgenera: larval abdomen without a pair of conical-shaped ventral tubercles; postgenal cleft variously shaped, viz., miter shaped, spearhead, bullet shaped or triangular; rectal papillae 3 simple lobe or compound lobes; pupal gill of 6-16 filaments; cocoon shoe, boot or slipper shaped; and head trichomes 3 pairs (1 facial+2 frontal). Habitat information and other ecological aspects of each species are provided. Updated keys to larvae and pupae of the Korean species of the subgenus Simulium are also provided to facilitate species identification. Taxonomic treatment based on external morphologies of larvae and pupae of Korean species of the subgenus Simulium are focused and included in this study. To understand their interspecific relationships, phylogenetic analyses using multiple data from molecule, morphology, and ecology are warranted in future research. Also continued exploration for new character systems is needed to establish more stable boundaries for subgenus and species delimitations.

A Morphological Study of Symplocaceae in Korea (한국산 노린재나무과의 형태학적 연구)

  • Park, Sang-Hong;Lee, Joongku;Kim, Joo-Hwan
    • Korean Journal of Plant Taxonomy
    • /
    • v.37 no.3
    • /
    • pp.255-273
    • /
    • 2007
  • The morphological characters for 4 taxa of Korean Symplocaceae were examined. Based on morphological examination, numerical analysis was performed to clarify the taxonomic relationships among the taxa. It was found that epidermal characters of leaves, cellular deposition of petals, cellular boundary of petioles, growth of stigmas and pollen grains and their surfaces were useful diagonostic characters. From the results of PCA analysis, four taxa were grouped as species clusters including each populations. Four species of Symplocos were clustered as species groups with clear delimitation. Morphological, numerical, and palynological analyses supported the previous morphological studies on this family.

Genetic Relationships among Typhula ishikariensis Varieties from Wisconsin

  • Chang, Seog-Won
    • Weed & Turfgrass Science
    • /
    • v.4 no.2
    • /
    • pp.135-143
    • /
    • 2015
  • Typhula ishikariensis Imai is a causal agent of Typhula snow mold, one of the most important turfgrass diseases in northern regions of the United States. Within Wisconsin isolates, there are three district groups clustered with known isolates of T. ishikariensis var. ishikariensis, var. canadensis and var. idahoensis as identified by RAPD markers. To further investigate the genetic relationship among these groups (varieties), monokaryon-monokaryon and dikaryon-monokaryon mating experiments were conducted. Mating types from var. ishikariensis, var. canadensis and var. idahoensis isolates were paired in all possible combinations. Pairings between var. canadensis and var. idahoensis were highly compatible, while no compatibility was detected between var. ishikariensis and either var. canadensis or var. idahoensis. These results indicate that var. ishikariensis is genetically separated from var. canadensis and var. idahoensis, whereas var. canadensis and var. idahoensis appeared to be genetically related to each other as a taxonomic unit. In the genetic relationship with the known biological species, var. ishikariensis and var. canadensis were genetically related to biological species I and II, respectively. However, var. idahoensis was not compatible with any of the biological species, suggesting that the pathogen may be in the process of biological speciation from var. canadensis.

Taxonomic study of three new Antarctic Asterochloris (Trebouxiophyceae) based on morphological and molecular data

  • Kim, Jong Im;Kim, Yong Jun;Nam, Seung Won;So, Jae Eun;Hong, Soon Gyu;Choi, Han-Gu;Shin, Woongghi
    • ALGAE
    • /
    • v.35 no.1
    • /
    • pp.17-32
    • /
    • 2020
  • Asterochloris is one of the most common genera of lichen phycobionts in Trebouxiophyceae. Asterochloris phycobionts associated with the lichenized fungi Cladonia and Stereocaulon in King George Island (Antarctica) and Morro Chico (Chile), were isolated and then used to establish clonal cultures. To understand the phylogenetic relationships and species diversity of Antarctic Asterochloris species, molecular and morphological data were analyzed by using three microscopy techniques (light, confocal laser and transmission electron) and a multi-locus phylogeny with data from the nuclear-encoded internal transcribed spacer (ITS) rDNA and the actin and plastid-encoded ribulose bisphosphate carboxylase large chain (rbcL) coding genes. Morphological data of three Antarctic strains showed significant species-specific features in chloroplast while molecular data segregated the taxa into distinct three clades as well. Each species had unique molecular signatures that could be found in secondary structures of the ITS1 and ITS2. The species diversity of Antarctic Asterochloris was represented by six taxa, namely, A. glomerata, A. italiana, A. sejongensis, and three new species (A. antarctica, A. pseudoirregularis, A. stereocaulonicola).

Alsidium oliveiranum sp. nov. (Rhodomelaceae, Rhodophyta), an overlooked species from the southwestern Atlantic based on morphology and DNA sequence data

  • Guimaraes, Silvia M.P.B.;Soares, Luanda Pereira;Fujii, Mutue Toyota;Diaz-Tapia, Pilar
    • ALGAE
    • /
    • v.34 no.3
    • /
    • pp.187-198
    • /
    • 2019
  • The exploration of seaweed diversity in poorly studied habitats has often led to the discovery of new species. Sand-covered rocks are an example, as they received less attention than sand-free rocky intertidal habitats during seaweed diversity surveys in Brazil. In sand-covered rocks from Espirito Santo and Rio de Janeiro we found an alga whose morphology was unique among rhodomelacean species previously reported in Brazil. With the aim to clarify the taxonomic identity of this species we studied its morphology, as well as its phylogenetic relationships. Molecular analyses resolved this species in the genus Alsidium (tribe Alsidieae) and differed from sequenced congeners with divergences ${\geq}2.5$ and 4.2% in the rbcL and cox1 genes, respectively. Morphological characters were in agreement with the genus Alsidium, and differed from other species currently recognized in the genus. The species consisted of a basal crust and scarcely branched erect axes with seven pericentral cells covered by a continuous layer of cortical cells. Reproductive structures were formed on clusters of short determinate branches. Therefore, the new species A. oliveiranum is proposed based on morphological and molecular evidence. Our findings contribute to better understand the diversity of the tribe Alsidieae, which is particularly diverse in the Americas.

Morphometric and Genetic Variation of Tropilaelaps Mites Infesting Apis dorsata and A. mellifera in Thailand

  • Suppasat, Tipwan;Wongsiri, Siriwat
    • Journal of Apiculture
    • /
    • v.33 no.4
    • /
    • pp.227-237
    • /
    • 2018
  • The majority parasitic bee mites of Thailand in genus Tropilaelaps are infesting colonies of native bees (Apis dorsata) and introduced bees (A. mellifera). The investigation aims to study morphological and genetic variation of Tropilaelaps mites infected different hosts. Adult mites were collected from honey bee brood throughout Thailand. Traditional and geometrical morphometrics were measured on photograph by using TPS program. Additional, COI gene variations were examined by PCR-RFLP and nucleotides sequencing. Tree of mites relationships were constructed by NJ and MP assumptions. Morphometric results indicated T. mercedesae were major species infesting on A. dorsata and A. mellifera. Mophological variation represented at anal and epigynial plate, which the shape of the anal plate apex margin has been key character to identify between T. mercedesae (bell to blunt shape) and T. koenigerum (pear shape). However, the discriminant analysis suggested that geometric results were potential to classify Thai Tropilaelaps populations from different hosts better than traditional morphometric. Otherwise, PCR-RFLP clearly detected the site of Dra I and Xba I digestion of Thai Tropilaelaps morphotypes. The COI sequences of T. koenigerum were founded infesting only A. dorsata in Thailand and four sequences that related to the Thai T. mercedesae morphotypes. The NJ and MP tree were clearly classified Thai Tropilaelaps species which were suggested both from morphological and molecular analysis. This information might be basically of taxonomic status, but this should have implication for controlling these mites in Thailand and other countries.

Wood Anatomy of Korean Symplocos Jacq. (Sympocaceae)

  • Balkrishna Ghimire;Beom Kyun Park;Seung-Hwan Oh;Dong Chan Son
    • Proceedings of the Plant Resources Society of Korea Conference
    • /
    • 2020.08a
    • /
    • pp.36-36
    • /
    • 2020
  • Symplocos Jacq. including about 350 species is the sole isolated genus of the family Symplocaceae. Despite poorly documented species delimitation and unresolved taxonomic nomenclature four species of Symplocos (S. coreana, S purnifolia, S sawafutagi, and S. tanakana) have been described in Korea. In this study, we carried the comparative wood anatomy of all the four species of Korean Symplocos to understand the wood anatomical variations within these four species. The result of this study indicated that Korean Symplocos are comparatively indistinguishable in terms of their qualitative wood features except for exclusively uniseriate rays present in S. purnifolia instead of uni- to- multiseriate in other three species. However, discrepancies are observed in quantitative wood variables such as vessel density, vessel size, and ray density. The vessel density of S. purnifolia (highest among the four species) is more than two times higher than the S. sawafutagi (lowest among the four species) and S. tanakana. On the other hand, vessel size is likewise reverse to the vessel number relationships i. e. vessel circumference and diameter in both planes of S. sawafutagi and S. tanakana is almost twice a larger than S. purnifolia. Interestingly, S. coreana remains in between of these two groups in terms of vessel features and closer to S. purnifolia in terms of ray density. The cluster analysis based on the paired group (UPGMA) algorithm using the Euclidean similarity index clearly differentiates S. purnifolia from the rest of the taxa representing the first isolated clade of the tree.

  • PDF

Characterizing Responses of Biological Trait and Functional Diversity of Benthic Macroinvertebrates to Environmental Variables to Develop Aquatic Ecosystem Health Assessment Index (환경변이에 대한 저서성 대형무척추동물의 생물학적 형질과 기능적 다양성 분석: 수생태계 건강성 평가 관점에서)

  • Moon, Mi Young;Ji, Chang Woo;Lee, Dae-Seong;Lee, Da-Yeong;Hwang, Soon-Jin;Noh, Seong-Yu;Kwak, Ihn-Sil;Park, Young-Seuk
    • Korean Journal of Ecology and Environment
    • /
    • v.53 no.1
    • /
    • pp.31-45
    • /
    • 2020
  • The biological indices based on the community structure with species richness and/or abundance are commonly used to assess aquatic ecosystem health. Meanwhile, recently functional traits-based approach is considered in ecosystem health assessment to reflect ecosystem functioning. In this study, we developed a database of biological traits for 136 taxa consisting of major stream insects (Ephemeroptera, Plecoptera, Trichoptera, Coleoptera, and Odonata) collected at Korean streams on the nationwide scale. In addition, we obtained environmental variables in five categories (geography, climate, land use, hydrology and physicochemistry) measured at each sampling site. We evaluated the relationships between community indices based on taxonomic diversity and functional diversity estimated from biological traits. We classified sampling sites based on similarities of their environmental variables and evaluated relations between clusters of sampling sites and diversity indices and biological traits. Our results showed that functional diversity was highly correlated with Shannon diversity index and species richness. The six clusters of sampling sites defined by a hierarchical cluster analysis reflected differences of their environmental variables. Samples in cluster 1 were mostly from high altitude areas, whereas samples in cluster 6 were from lowland areas. Non-metric multidimensional scaling (NMDS) displayed similar patterns with cluster analysis and presented variation of taxonomic diversity and functional diversity. Based on NMDS and community-weighted mean trait value matrix, species in clusters 1-3 displayed the resistance strategy in the life history strategy to the environmental variables whereas species in clusters 4-6 presented the resilience strategy. These results suggest that functional diversity can complement the biological monitoring assessment based on taxonomic diversity and can be used as biological monitoring assessment tool reflecting changes of ecosystem functioning responding to environmental changes.

Phylogenetic Relationships of Korean Campanulaceae Based on PCR-RFLP and ITS Sequences (PCR-RFLP와 ITS 염기서열 분석을 이용한 한국산 초롱꽃과(Campanulaceae)의 계통유연관계)

  • Kim, Kyung-Ah;Yoo, Ki-Oug
    • Korean Journal of Plant Taxonomy
    • /
    • v.41 no.2
    • /
    • pp.119-129
    • /
    • 2011
  • Phylogenetic studies were conducted to evaluate the taxonomic relationships among 27 taxa, including 2 outgroups of Korean Campanulaceae, using PCR-RFLP analysis and ITS sequences. In the PCR-RFLP analysis, 15 restriction endonucleases produced 244 restriction sites and size variations from the chloroplast DNA, and 59 restriction sites (24%) showed polymorphism. The length of the ITS regions ranged from 588 bp to 797 bp. The sequence divergence including the outgroups is 0-39.36%. Phylogenetic analyses based on PCR-RFLP and ITS data suggest that Campanulaceae is monophyletic; Codonopsis and Platycodon forms an independent clade; the Peracarpa and Asyneuma clade is a sister to the Adenophora-Hanabusaya clade; Campanula is monophyletic; and Wahlenbergia basally branches within the ITS tree, whereas they are placed between Campanula and the Codonopsis-Platycodon clade in the PCR-RFLP tree; Hanabusaya is placed within the Adenophora clade; and Adenophora is paraphyletic and shows discordance to the infrageneric classifications based on morphological data. The present results show two data sets, largely congruent at the generic level, but their phylogenetic positions, in particular the Wahlenbergia and Hanabusaya and the infrageneric classifications in Adenophora, show some incongruence.