Soil ciliates were first reported in South Korea by Shin (1993), and currently, more than 100 species are known (Jung et al., 2017; Kwon et al., 2019). In the plant rhizo sphere, soil ciliates mineralize nutrients and play an important role in plant nutrition (Ekelund and Rønn, 1994; Li et al., 2010). They also regulate soil microbial biomass and community composition (Lousier and Bam forth, 1988; Gel’tser, 1991; AcostaMercado and Lynn, 2004), making them a reliable soil environmental bio marker (Foissner, 1987a; 1997; 1999; Li et al., 2010). The genus Anteholosticha Berger, 2003 is characterized by a continuous adoral zone of membranelles, three en larged frontal cirri, buccal cirrus or cirri, frontoterminal cirri, midventral pairs only, more midventral pairs than number of transverse cirri, one left and one right marginal rows, and caudal cirri lacking. Ten Anteholosticha species have been recorded in South Korea (Jung et al., 2017; Moon et al., 2017; Kim and Min, 2018). The genus Bakuella Agamaliev & Alekperov, 1976 is characterized by a continuous adoral zone of membrane lles, three frontal cirri, one or more buccal cirri, two or more frontoterminal cirri, midventral complex composed of midventral pairs and midventral rows, one left and one right marginal row, and transverse cirri (Berger, 2006). Three Bakuella species have been recorded in Korea (Jo et al., 2015; Kim et al., 2018): Bakuella (Bakuella) incheonesis Jo et al., 2015, Bakuella (Psuedobakuella) lit o ralis Jo et al., 2015, and Bakuella marina Agamaliev and Alekperov, 1976. Herein, we report two soil ciliate species new to Korean and provide morphological descriptions and the small sub unit ribosomal RNA (18S rRNA) gene sequences.
Diatoms are groups of eukaryotic unicellular micro algae and are some of the most common organic matter in an aquatic ecosystem. They play an important role as the primary producers in freshwater and marine environ ments, and they contribute significantly to the photosyn thesis activity on Earth (Lee et al., 2019). In addition, dia toms are used widely across the world for environmental monitoring because different species of diatom typically have specific habitat preferences, and they react quickly to environmental changes (Dixit et al., 1992; Round et al., 2007). For example, species like Cyclotella meneghiniana and Thalassiosira pseudonana (Baek et al., 2011; Adenan et al., 2013) have distinct ranges of pH and salinity where they will grow (Spaulding et al., 2019). In addition, they have ranges and tolerance for other environmental factors, such as nutrient concentration, suspended sediment, flow regime, elevation, and for different types of human distur bances (Spaulding et al., 2019). Hence, they are consid ered susceptible indicators of water quality and environ mental change. For these reasons, diatoms have received considerable attention from past and ongoing research (Dixit et al., 1992; Adenan et al., 2013; Hilaluddin et al., 2020). In general, diatoms have been discriminated morphologi cally by using a light microscope (LM) and scanning elec tron microscope (SEM). However, some diatoms may have few discernible structural differences when viewed with a microscope. In addition, different lineages have often adapted in similar ways to analogous habitats. As a result, there are many examples of diatoms species that look very similar at the microscopic level, but are not closely related (Graham et al., 2009). Since the early 1980s, molecular techniques by using carbohydrates, toxins, proteins, and nucleic acids as markers have been developed to detect and discriminate phytoplankton (Ebenezer et al., 2012; Sun et al., 2012). Among DNA based methods such as terminal restriction fragment length polymorphism, micro array, realtime PCR, the highthroughput sequencing (HTS) of smallsubunit rRNA genes from environmental DNA techniques has already been widely applied for the assessment of microbial diversity and microplanktonic community structure (Eiler et al., 2012; Ghiglione and Murray, 2012). These methods allowed high resolution and rapid analysis of microbial and phytoplankton com Journal of Species Research 10(1):4656, 2021
Although the high level of species diversity within the Pholcus phungiformes-group (Araneae: Pholcidae) in the Korean Peninsula has been recognized recently, taxonomic studies, including new species discovery, have not been conducted in western regions of South Korea. In this study, five additional species belonging to the Pholcus phungiformes-group discovered from Seoul and surrounding areas are described as new, viz., Pholcus seoulensis Lee Lee, sp. nov. Pholcus suraksanensis Lee Lee, sp. nov., Pholcus incheonensis Lee Lee, sp. nov., Pholcus seokmodoensis Lee Lee, sp. nov. and Pholcus chilgapsanensis Lee Lee, sp. nov. Detailed descriptions and geographic distributions are provided with accompanying photographs.
Whereas freshwater ecosystems cover only less than 1% of the Earth’s surface, fresh waters are vulnerable to climate change and thus considered to be indicators for global warming. As prokaryotic microorganisms inhabiting freshwater ecosystems play an essential role in ecosystem functioning, it is important to cultivate key microbial taxa for the elucidation of their physiology, metabolism, and ecological niches. In 2006, National Institute of Biological Resources (NIBR) launched the research program of ‘The Survey of Korean Indigenous Species,’ and in 2016, the Nakdonggang National Institute of Biological Resources (NNIBR) also started a similar research grant named ‘Survey of freshwater organisms and specimen collection (Prokaryotes)”. Owing to these research programs, many unrecorded or new prokaryotic species have been discovered from diverse freshwater ecosystems on the Korean Peninsula (i.e, Jeon et al., 2017; NIBR, 2017; Joung et al., 2018; Joung et al., 2019). The study reported herein is a part of the research program supported by NNIBR, focusing on the isolation of unrecorded bacterial species from diverse habitats of the Han River watershed. In 2020, we targeted to isolate previously unrecorded bacterial species in water or sediment samples collected from eight different Han River watershed stations (Hanpo, Anyang, Gyeongan, and Hadong streams; Chungju, Cheongpyong, and Soyang lakes; and Janghang wetland). Bacterial cultivation was conducted under aerobic conditions, except for samples collected from the Gyeongan stream and the Janghang wetland, which were conducted under anaerobic conditions. Journal of Species Research 10(3):227-236, 2021
