AUTHOR=Tsai Sheng-Fang , Lee Meng-Lun , Chiang Kuo-Ping 

TITLE=Morphological, Molecular, and Growth Characteristics of a Cryptic Species, Strombidium parasulcatum n. sp. (Alveolata: Ciliophora: Oligotrichida)

JOURNAL=Frontiers in Microbiology

VOLUME=12

YEAR=2022

URL=https://www.frontiersin.org/journals/microbiology/articles/10.3389/fmicb.2021.770768

DOI=10.3389/fmicb.2021.770768

ISSN=1664-302X

ABSTRACT=<p>A new marine planktonic ciliate from Taiwan, <italic>Strombidium parasulcatum</italic> sp. n., is described based on live observations, protargol staining, and molecular data. Its morphological characters are similar to those of <italic>Strombidium sulcatum</italic> Claparède and Lachmann, 1859 sensu Song et al., 2000 but differ from <italic>S. sulcatum</italic> sensu Fauré-Fremiet, 1912 and sensu Fauré-Fremiet and Ganier, 1970 by several morphological characters. The 18S rRNA gene sequences of the two forms display 76 base pair differences (about 5%), indicating that they should be considered separate species. The highest observed specific growth rates of <italic>S. parasulcatum</italic> in culture were 1.79 day<sup>–1</sup> over 1 day and 1.52 day<sup>–1</sup> over 2 days, both starting at day 5. Bacteria appear to be an important food resource for the cultivation of this medium-sized oligotrich ciliate. This and other recent studies suggest that cryptic species may be common in the genus <italic>Strombidium</italic>, and an integrative approach including morphological, ecological, and molecular data should be used to address this question.</p>