The establishment of ecological conservation for herpetofauna species in hotspot areas of South Korea.

Understanding the geographic distribution of species is crucial for establishing protected areas. This study aimed to identify the preferred habitat environment of South Korean herpetofauna using distribution point information, providing the information necessary to protect their habitat by establishing a species distribution model. We found that climate variables in the region where 19 amphibians and 20 reptiles were distributed correlated with the altitude, suggesting that altitude had a major influence on their distribution. The species distribution modeling indicated that 10-12 amphibian and 13-16 reptile species inhabit the Gangwon-do region, forming hotspot areas in the eastern and western regions around the Taebaek Mountains. Some of these hotspot areas occurred in the Demilitarized Zone and national parks, which are government-managed ecological conservation areas. However, some hotspot areas are vulnerable to habitat destruction due to development and deforestation as they are not designated conservation areas. Therefore, it is necessary to establish new conservation areas with a focus on herpetofauna after confirming the actual inhabitation of species through precise monitoring in predicted hotspot areas and designating them as protected areas. Our results can serve as important basic data for establishing protection measures and designating protected areas for herpetofauna species.

Ozobranchus jantseanus (Clitellata: Ozobranchidae) from Reeve's Turtle, Mauremys reevesii: New Annelid Fauna in Korea.

Turtle leeches have not been recorded in Korea, although they occur in geographically adjacent countries including China and Japan. This study describes a turtle leech, Ozobranchus jantseanus (Clitellata: Ozobranchidae), found from Reeve's turtle (Mauremys reevesii) in Korea. Of the 143 Reeve's turtles collected from the freshwater reservoir in Jinju City, Gyeongsangnam-do, Korea, 95 unidentified leeches were found in 8 (5.6%) individuals. The leeches had 22 somites with 11 pairs of externally exposed branchiae, body-sized posterior suckers, and spines on the dorsal surface. We identified these leeches as Ozobranchus jantseanus Oka, 1912 (Clitellata: Ozobranchidae). This species of turtle leeches found in Korea may fill the gap in the biodiversity of East Asian annulus.

Distribution Change of Invasive American Bullfrogs (Lithobates catesbeianus) by Future Climate Threaten Endangered Suweon Treefrog (Hyla suweonensis) in South Korea.

The American Bullfrog (Lithobates catesbeianus) has been imported into South Korea in earnest for food since the 1970s and introduced into nature due to release and escape. Accordingly, the influx and spread of American Bullfrogs are expected to have a direct impact on native species, but few related studies have been conducted on this. We predicted changes in the potential distribution and future distribution based on climate change scenarios to analyze how those changes affect critically endangered Suwon treefrogs. Suwon treefrog sites (63.9%, 78/122) overlapped with the distribution of Bullfrogs. According to the prediction of the future distribution of Bullfrogs, the overlapping of American Bullfrogs and Suwon treefrog will remain similar to the current level in the Representative Concentration Pathway (RCP) 4.5 scenario. On the other hand, in the RCP 8.5 scenario, the number of overlapping sites will increase to 72.1% (88/122) due to the spreading of the American Bullfrogs. The results show that climate change directly affects the distribution expansion of the American Bullfrogs but also indirectly can lead to an increased threat to Suwon treefrogs. In conclusion, our results strongly suggest why climate change should be actively addressed in terms of the spread of invasive species and the protection of endangered species.

Complete mitochondrial genome of the Small Salamander in Korea, Hynobius unisacculus (Anura: Hynobiidae).

The complete mitochondrial (mt) genome of Hynobius unisacculus was sequenced and characterized. The circular mt genome constituted of 37 genes (13 protein-coding genes, 22 transfer RNAs, and 2 ribosomal RNAs) and a non-coding region (NCR). Phylogenetic analysis based on the full mt genome sequences confirmed that H. unisacculus was closely related to Hynobius leechii rather than other Hynobius species. This is the first completed mt genome from H. unisacculus, which provides data for further study of phylogeny in Hynobiidaes.

Complete mitochondrial genome of the American bullfrog in Korea, Lithobates catesbeianus (Anura: Ranidae).

The complete mitochondrial (mt) genome of Lithobates catesbeianus was sequenced and characterized. The circular mt genome was constituted of of 37 genes (13 protein-coding genes, 22 transfer RNAs, and 2 ribosomal RNAs) and a non-coding region (NCR). Phylogenetic analysis based on the full mt genome sequences confirmed that among the genus Lithobates, L. catesbeianus Korea is included in a monophyletic group with L. catesbeianus China, but not with either L. catesbeianus Japan or L. catesbeianus Canada. This is the first completed mt genome from L. catesbeianus Korea, which provide data for further study of phylogeny in Lithobates spp. that have been introduced into a number of different countries originally from North America.

Northward dispersal of sea kraits (Laticauda semifasciata) beyond their typical range.

Marine reptiles are declining globally, and recent climate change may be a contributing factor. The study of sea snakes collected beyond their typical distribution range provides valuable insight on how climate change affects marine reptile populations. Recently, we collected 12 Laticauda semifasciata (11 females, 1 male) from the waters around southern South Korea-an area located outside its typical distribution range (Japan, China including Taiwan, Philippines and Indonesia). We investigated the genetic origin of Korean specimens by analyzing mitochondrial cytochrome b gene (Cytb) sequences. Six individuals shared haplotypes with a group found in Taiwan-southern Ryukyu Islands, while the remaining six individuals shared haplotypes with a group encompassing the entire Ryukyu Archipelago. These results suggest L. semifasciata moved into Korean waters from the Taiwan-Ryukyu region via the Taiwan Warm Current and/or the Kuroshio Current, with extended survival facilitated by ocean warming. We highlight several contributing factors that increase the chances that L. semifasciata establishes new northern populations beyond the original distribution range.

Life History of a Unique Asian Plethodontid Salamander, Karsenia koreana.

Using preserved specimens, we studied the basic life history of the topotypic population of the unique Asian plethodontid salamander, Karsenia koreana. Of 51 individuals examined, 11 males and 13 females were judged as mature from the development of gonads. The ovarian eggs were large (diameter 3.7-4.8 mm) and yellow to orange in color, and the clutch size was about 8-10. These values approximate those of actually spawned eggs recently reported. Skeletochronological analyses revealed the average age of males (5.3 years) to be lower than females (7.3 years). The age at maturity and maximum observed longevity were four and nine years in males and five and 10 years in females, respectively. In the growth curves estimated by a von Bertalanffy growth model, the growth coefficient and asymptotic SVL did not differ between the sexes, although males (40.6 mm) were smaller than females (45.3 mm) in the average snout-vent length. The time and place of courtship behavior, oval development, hatching, and especially, whether the species shows aquatic larval stage or direct development, are important topics to be resolved in future.

Complete mitochondrial genomes of Scincella vandenburghi and S. huanrenensis (Squamata: Scincidae).

Here, we report the complete mitochondrial genomes of the skink species Scincella vandenburghi and S. huanrenensis. The mitogenomes were determined to be 17103 bp for S. vandenburghi and 17212 bp for S. huanrenensis. The mitogenomes consist of 13 protein-coding genes, two rRNA genes, 22 tRNA genes and two non-coding regions. We then used the mitogenome data to construct a phylogenetic tree for these two species and an additional 16 species within the suborder Lacertilia.