Morphological Description and Molecular Phylogeny of Two Species of Levicoleps (Ciliophora, Prostomatida), L. taehwae nov spec. and L. biwae jejuensis nov subspec., collected in Korea

摘要

Two colepid ciliates, Levicoleps taehwae nov. spec. and L. biwae jejuensis nov. subspec., were collected from the brackish water of the Taehwa River and a small freshwater pond in Jeju Island, South Korea, respectively. Their living morphology, infraciliature, and small subunit (SSU) rRNA gene sequences were determined using standard methods. Barrel-shaped L. taehwae nov. spec. is a small ciliate with an average size of 45 9 25 mu m in vivo, about 15 ciliary rows each composed of 12 monokinetids and two perioral dikinetids, and two 20 mu m-long caudal cilia. The sequence length and GC content of the SSU rRNA gene are 1,669 bp, 44.5%. This novel species is similar in body size to Coleps hirtus, and has six armor tiers and hirtus-type tier plates, and the same number of ciliary rows as C. hirtus; however, it can be distinguished from the latter by the absence of armor spines and its sequence similarity of SSU rRNA gene is about 92.8% which indicates that it is a distinct form. Levicoleps biwae jejuensis nov. subspec., is a medium colepid ciliate which has a barrel-shaped body, about 22 somatic kineties and 16 transverse ciliary rows, three mini adoral organelles, and four 15 mu m-long caudal cilia. The sequence length and GC content of the SSU rRNA gene are 1,666 bp and 44.4%.