Unarmored and thin-walled dinoflagellates were collected from brackish and coastal waters of Korea from August 2019 to August 2021. A total of 10 species belonging to orders Sussiales and Gymnodiniales were isolated and established as clonal cultures. Of them, five species (Biecheleria brevisulcata, Lepidodinium chlorophorum, Karlodinium decipiens, Kirithra asteri, and Wangodinium sinense) are newly recorded in Korea and examined using a light microscope (LM) and a scanning electron microscope (SEM). Their molecular phylogeny was inferred from LSU rDNA sequences. Here, we present taxonomic information, morphological features, and molecular phylogenetic positions of these unrecorded dinoflagellate species.

The genus Chroomonas is a group of blue-green colored cryptomonads. This study describes two freshwater Chroomonas species for the first time in South Korea: Chroomonas nordstedtii Hansgirg and Chroomonas coerulea (Geitler) Skuja. We examined the morphology and ultrastructure of these species by light microscopy, scanning electron microscopy, and transmission electron microscopy. These two Chroomonas species were blue-green colored and ovate to oval-shaped. Chroomonas nordstedtii was characterized by two Maupas ovals with hexagonal periplast plates, whereas C. coerulea was characterized by one eyespot with rectangular periplast plates. A molecular phylogeny with data from nuclear SSU rRNA and chloroplast rbcL genes revealed that Korean C. nordstedtii formed a distinct clade with NIES-708, NIES-1004 from Japan, and UTEX 2779 from Colorado, USA, while C. coerulea formed a clade with ACOI 1366 from Portugal.

Two linyphiid spiders, Saitonia kawaguchikonis Saito & Ono, 2001 and Asthenargus niphonius Saito & Ono, 2001 were confirmed from Korea for the first time. Males of S. kawaguchikonis and a female of A. niphonius were collected with pitfall traps in a leaf litter of mixed forests in three National Parks (Hallyeohaesang National Park, Mt. Naejangsan, and Mt. Sobaeksan) during the seasonal surveys for the spider fauna in mountainous terrain from 2018 to 2020. These two species were formerly known from China and Japan, or only from Japan, respectively. The present study describes these two species with measurements, morphological illustrations, and a distribution map. This report adds the genus Asthenargus Simon & Fage, 1922 from Korea to the Korean spider fauna for the first time.

Cyanobium is a genus of picoprokaryotic cyanophytes, which includes species worldwide. The present study investigated the morphology, ultrastructure, and molecular phylogeny of the unrecorded genus Cyanobium Rippka & Cohen-Bazire 1983 and species Cyanobium gracile Rippka & Cohen-Bazire 1983. A C. gracile culture from a freshwater sample collected from the Adongji pond was established by singlecell isolation. Morphological data were analyzed using light and transmission electron microscopy. C. gracile lives as solitary cells without gelatinous envelopes and is ovate, oval, or shortly rod-shaped. Thylakoids are laid along the cell walls, with three thylakoid membranes parallel to each other. Nucleoplasm was observed in the center of the cell. Molecular phylogeny performed with data from 16S small subunit ribosomal DNA gene (SSU rDNA) sequences showed that the three strains of C. gracile, including the type strain (PCC6307) and a newly recorded strain (Adong101619), formed a distinct clade with a high supporting value (maximum-likelihood=100, pp=1.00). Based on morphology and molecular data, we report the newly recorded C. gracile in Korea.

맵시벌상과에 속하는 Testudobracon pleuralis Ashmead, 1906, Diadromus subtilicornis Gravenhorst 1829 2속 및 2종을 한국에서 처음으로 보고한다. 본 종의 형태진단, 분포, 삽화를 수록한다.

The genus Petroderma never been reported from the coast of Korea. In this study, our collection from Chaeseokang is matched with P. maculiforme morphologically. Petroderma maculiforme is characterized by having small irregular light to dark brown crusts, a basal layer of irregularly shaped cells giving rise to erect parallel filaments which easily separate with pressure, single chromatophore per cell, small spherical to cylindrical unilocular sporangia in a terminal position, and plurilocular sporangia narrower than erect filaments or wider and shorter than erect filaments in a terminal position. In addition, Hineksia sordida was also collected from Korea. It is mostly epiphytic and characterized by uniseriate filamentous thalli forming loose tangled masses, sparse and spiral branching, some long lateral branches, rhizoids occurring throughout the plant, plurilocular and unilocular sporangia scattered on separate plants. Our molecular analyses based on the rbcL gene reveal that our samples of P. maculiforme and H. sordida are nested within the clades of Petroderma and Hincksia, respectively. Therefore P. maculiforme and H. sordida are reported as new records from Korea based on morphological and molecular analyses.

Acinetospora filamentosa and Microspongium stilophorae are reported as new records from South Korea based on morphological and molecular analyses. A. filamentosa is mainly characterized by having the sparsely branched erect filaments, the scattered meristematic zones, forming crampons, plurilocular sporangia on both prostrate filaments and lower part of erect filaments, and spherical to oval unilocular sporangia formed either sessile or with a pedicel. M. stilophorae is an epiphytic thalli mostly on Stilophora sp. It is characterized by prostrate filaments with irregular cells, short erect filaments with short ramuli, phaeophycean hairs, uniseriate plurilocular sporangia on the terminal part of erect filament. Our molecular analyses of rbcL and cox1 genes reveals that A. filamentosa and M. stilophorae are nested within the clades of Acinetospora and Microspongium, respectively.

한국에서 Temnothorax michali Radchenko 삼색도토리개미(신칭), Temnothorax pisarskii Radchenko 띠도토리개미(신칭), Temnothorax wui (Wheelr) 곰보도토리개미(신칭), Temnothorax xanthos Radchenko 누리도토리개미(신칭)가 분포함을 보고한다. 종에 대한 형질과 사진을 포함하여 분류학적 정보를 제공한다.한국에서 Temnothorax michali Radchenko 삼색도토리개미(신칭), Temnothorax pisarskii Radchenko 띠도토리개미(신칭), Temnothorax wui (Wheelr) 곰보도토리개미(신칭), Temnothorax xanthos Radchenko 누리도토리개미(신칭)가 분포함을 보고한다. 종에 대한 형질과 사진을 포함하여 분류학적 정보를 제공한다.

The Genus Eugahania Mercet belongs to the family Encyrtidae (Hymenoptera: Chalcidoidea), containing 8 species in the world. They are mostly parasitoids on the nymphs of leafhoppers (Hemiptera). Until now, Eugahania have been barely studied in the world. In this study, the genus Eugahanua is reported for the first time from Korea including two new records. A key to the species, and diagnoses and photographs for each species are provided.