Jong-Geun Park

A new genus and six new species of the Parabathynellidae (Bathynellacea, Syncarida) from the Kimberley region, Western Australia

Six new species of a new genus of the Parabathynellidae are described from the Kimberley Region, Western Australia. The erection of the new genus, Kimberleybathynella gen. nov., is based on the two‐segmented antenna, the partial fusion of the second and third segments of the maxilla, and the setal condition of the uropodal exopodite, where the outer seta is longer than the inner one. The one‐segmented exopodite of thoracopods I–VII and hemispherical form of male thoracopod VIII suggest the close relationship of Kimberleybathynella to the genus Atopobathynella.

Selective detection of viable Helicobacter pylori using ethidium monoazide or propidium monoazide in combination with real-time polymerase chain reaction

Because Helicobacter pylori has a role in the pathogenesis of gastric cancer, chronic gastritis and peptic ulcer disease, detection of its viable form is very important. The objective of this study was to optimize a PCR method using ethidium monoazide (EMA) or propidium monoazide (PMA) for selective detection of viable H. pylori cells in mixed samples of viable and dead bacteria. Before conducting the real‐time PCR using SodB primers of H. pylori, EMA or PMA was added to suspensions of viable and/or dead H. pylori cells at concentrations between 1 and 100 μM. PMA at a concentration of 50 μM induced the highest DNA loss in dead cells with little loss of genomic DNA in viable cells. In addition, selective detection of viable cells in the mixtures of viable and dead cells at various ratios was possible with the combined use of PMA and real‐time PCR. In contrast, EMA penetrated the membranes of both viable and dead cells and induced degradation of their genomic DNA. The findings of this study suggest that PMA, but not EMA, can be used effectively to differentiate viable H. pylori from its dead form.

Detection and genotyping of vancomycin-resistant Enterococcus spp. by multiplex polymerase chain reaction in Korean aquatic environmental samples

The distribution characteristics of Enterococcus spp., which are indicators of fecal pollution, were investigated at 33 sites within the 3 major water systems of Korea. Enterococci were detected at concentrations ranging from 1 to 37 CFU/100mL in 41 of 132 samples (31.1%) from the 3 major water systems. The overall average detected concentration was 1.2 CFU/100mL, while the average concentration for all detection sites was 5.3 CFU/100mL. After optimized multiplex polymerase chain reaction (PCR) was performed with newly developed VanA, VanB, VanC-1, and VanC-2/3 primers, concentrations of vancomycin-resistant Enterococcus spp. (VRE) ranging from 1 to 23 CFU/100mL were detected in 17 of 132 samples (12.9%). Of 216 individual enterococcal colonies, 64 (29.6%) displayed the VanC genotype. The results of a susceptibility test to vancomycin showed that the range of the minimal inhibitory concentration (MIC), an indicator of bacterial resistance, was 4 to 24μg/mL, with the average MIC at 9.2±4.5μg/mL. Of the bacterial isolates, 1 colony with the VanC-1 genotype was identified as E. gallinarum by 16S rDNA sequencing, whereas the other 63 colonies had the VanC-2/3 genotype and were identified as E. casseliflavus. Although these results imply that the major head bays of Korea are not contaminated with the highly vancomycin-resistant VanA- or VanB-type VREs, the misuse of antibiotics should be prohibited to minimize the presence of VREs and to maintain a safe water supply for protecting the health of the general population. Based on the study results, we also recommend the implementation of a continuous, broad-spectrum inspection program for Enterococcus spp. and VRE contamination in the major head bays. Furthermore, the multiplex PCR method described in this study can be used effectively for this purpose.

A preliminary inquiry into an Asian topsy‐turvy Dom, Allobathynella with the description of a new species from South Korea and redescription of A. japonica (Crustacea, Syncarida, Parabathynellidae)

Allobathynella japonica Morimoto and Miura, 1957 and a new species of Allobathynella from South Korea are described with detailed descriptions of each male thoracopod VIII. The new species, A. shinjongieei sp. nov., differs from its congeners in having a median seta on the inner margin of the fifth antennular segment, ten spines on the uropodal sympod and in the absence of an epipod in thoracopods I–III. Allobathynella shinjongieei belongs to the mirabilis group which otherwise includes A. japonica, A. mirabilis and A. coreana. The mirabilis group is assumed to be a distinct taxonomic unit. The supporting characters for this assumption are the bell‐formed male thoracopod VIII attaching perpendicularly to the body which has a flat and round epipod, the absence of the mandibular proximal tooth and the absence of the seta on the pleotelson.

New genus and two new species of Parabahtynellidae (Malacostraca: Syncarida) from South Korea

We erect Hangangbathynella n. gen. to accomodate two new parabathynellid species, H. taechooni and H. eunokae, collected from subterranean water in South Korea. The new genus is characterized by: the 7-segmented antennules and antennae, absence of a medial seta on the second maxillary segment, a 2-segmented exopod of thoracopods I-VII, oval form of the male thoracopod VIII with penial organ displaying a smooth surface and gourd-shaped epipod, absence of pleopods, uropodal protopod with homonomous spines, pleotelson with one lateral seta near the base of the furcal rami and protruding anal operculum with sharp triangular process. The two new species differ in body size, in the number of spines of the uropodal protopod, in setae on the third maxillary segment, in the number of the spines on the mandibular spine row, as well as in the form of female thoracopod VIII.

Two new species of Arisubathynella Park and Eun, 2012 (Malacostraca: Syncarida: Parabathynellidae) from South Korea

Two new species of the parabathynellid genus Arisubathynella Park and Eun, 2012 are described from South Korea. Arisubathynella imjinensis sp. nov. is characterized by the presence of two setae (instead of one seta) on the inner margin of the first antennular segment, the plumose seta on the distal antennal segment longer than other simple setae, the male thoracopod VIII with a dental lobe carrying six teeth and with a smooth lower lobe of the exopod, the presence of a ctenidium on the inner margin of the uropodal endopod and the relative length of setae on the uropodal exopod; A. hongcheonensis sp. nov. is outstanding in having six spines on the mandibular spine row, in the presence of only two claws on the fourth endopodal segment of the thoracopod I and in having five teeth on the dental lobe of the male thoracopod VIII. A careful comparison with the single known species, A. cheongmiensis Park and Eun, 2012, enables us to revise the generic diagnosis. The distally 2-lobed epipod of the male thoracopod VIII and the absence of the medial seta on the second maxillar segment suggest a close relationship between the two new species. Based on a 1-segmented exopod on the thoracopod I, a bell-shaped male thoracopod VIII and an uropod with sympod carrying inhomonomous spines, with endopod drawn out into a spur, and with exopod carrying a strong seta on its inner margin, we assume a close relationship between Arisubathynella and Nipponbathynella Schminke, 1973.

Redefinition of Nipponbathynella based on the four new species from East Asia (Crustacea: Bathynellacea: Parabathynellidae)

Four new species of the parabathynellid genus Nipponbathynella Schminke, 1973 are described from South Korea (Nipponbathynella leesookyungae sp. nov., Nipponbathynella donggangensis sp. nov. and Nipponbathynella wanjuensis sp. nov.) and Japan (Nipponbathynella shigaensis sp. nov.), raising the number of known species to seven. Nipponbathynella leesookyungae is characterized by the convex ventral surface of the labrum and the rich ornamentation (with three spinules and two teeth) of the exopod of male thoracopod VIII; N. donggangensis by the distal spine on the distal maxillular segment with many dentils; N. wanjuensis by the endopod of the male thoracopod VIII with one seta (instead of two) and the serrated endopodal spur of the uropod; and N. shigaensis by the basipod of thoracopods II–VII carrying strong hairs on their outer margin. The three new and one known (Nipponbathynella pectina) South Korean species share a bur-like inner lobe of the male thoracopod VIII, suggesting their close relationship. Based on the one-segmented exopod on thoracopod I and two-segmented exopod on the thoracopods II–VII, the bell-shaped male thoracopod VIII and the uropod with sympod carrying a large distal spine in addition to several proximal spines of smaller size, with endopod drawn into a spur and with exopod carrying a seta, a close phylogenetic relationship between Nipponbathynella and Arisubathynella Park and Eun, 2012 is proposed. http://zoobank.org/urn:lsid:zoobank.org:pub:9650379F-C249-473C-AAA4-B3D638B96322