Identification of New Sub-Fossil Diatoms Flora in the Sediments of Suncheonman Bay, Korea

Abstract

Suncheonman Bay, Korea’s most representative estuary, is an invasive coastal wetland composed of 22.6 km2 of tidal flats surrounded by the Yeosu and Goheung Peninsulas. In January 2006, this region was registered in the Ramsar Convention list in Korea, representing the first registered wetland. Estuaries are generally known to have high species diversity. In particular, several studies have been conducted on planktonic and epipelic diatoms as primary producers. Suncheonman Bay has already been involved in many biological and geochemical studies, but fossil diatoms have not been evaluated. Therefore, we investigated fossil diatoms in Suncheonman Bay and introduced sub-fossil diatoms recorded in Korea. One sedimentary core has been extracted in 2018. We identified 87 diatom taxa from 52 genera in the SCW03 core sample. Of these, six species represent new records in Korea: Cymatonitzschia marina, Fallacia hodgeana, Navicula mannii, Metascolioneis tumida, Surirella recedens, and Thalassionema synedriforme. These six newly recorded diatom species were examined by light microscopy and scanning electron microscopy. The ecological habitats for all the investigated taxa are presented.

Giffenia koreana sp. nov. (Bacillariophyta): A newly identified epipelic diatom in the tidal flat sediments of Suncheonman Bay, extant for over 1,400 Years

“…nov., was initially reported as an unidentified species (Giffenia sp.) in a previous study (Park et al 2021). Subsequently, the species was confirmed to be novel through extensive electron microscopic analyses and a review of references.…”

“…nov. is found in all sections from 0.1 m to 6.0 m at 0.5 m intervals in core SCW03, both in this study and the previous report (as Giffenia sp.) (Park et al 2021). Considering the AMS age-dating results of core SCW03 (Park et al 2021), this species, identified as G.…”

“…In a subsequent taxonomic study, we observed and identified the unknown Giffenia taxon reported by Park et al (2021). The present study aims to describe this species as new to science using extensive light microscopy (LM) and scanning electron microscopy (SEM) observations, as well as comparisons with globally described Giffenia taxa.…”

“…In our previous study, Park et al (2021) investigated fossil diatoms and identified 87 diatom taxa, including six newly recorded diatom species in the Republic of Korea. These were sampled from a sedimentary core (SCW03) in Suncheonman Bay.…”

Taxonomy and Ecology of Marine Algae

“…Park et al [6] investigated fossil diatoms in Suncheonman Bay and introduced subfossil diatoms recorded in Korea. One sedimentary core has been extracted in 2018.…”