Porphyrosiphon annulatus D. Kim, N. Lee, S. Yoon, T. Kim, Ki & O. Lee, 2022

Kim, Do-Hyun, Lee, Nam-Ju, Yoon, Sung-Ro, Kim, Taehee, Ki, Jang-Seu & Lee, Ok-Min, 2022, Porphyrosiphon annulatus sp. nov. (Oscillatoriales, Cyanobacteria) isolated on moist soil in Suwon, Republic of Korea, Phytotaxa 532 (3), pp. 288-300 : 293

Porphyrosiphon annulatus D. Kim, N. Lee, S. Yoon, T. Kim, Ki & O. Lee sp. nov. ( Fig. 2 )

Description: Thallus tomentose, expanded, and blue-green to yellowish-brown. Filament straight or slightly curved and up to 30 µm in width, a filament contains a solitary trichome, but occasionally two. Sheaths firm and thick, longitudinally and transversely annular lamellated, yellowish-brown in nature. Sheaths initially colorless and later yellow-brown or pink in the culture. Trichome blue to green, constricted at the cross-walls, not attenuated at the end, motile. Cells flat rectangle with L/W 1/3–1/4, 4.2–6.1 μm long and 11.1–23.2 μm wide. Apical cells conical or round without calyptra. Reproduction with hormogonia formed by necridic cells.

Diagnosis: Porphyrosiphon annulatus had a relatively large trichome by the interspecies comparison, possessed shorter and flatter rectangular cells compared to the type species P. notarisii , and displayed transversely annular lamellations in the sheath.

Etymology: “ annulatus ” was named so because sheath yielded a feature of transversely annular lamellations.

Holotype (designated here): A formalin fixed specimen, NIBRCY0000001276 in the Herbarium at the National Institute of Biological Resources (KB), from cultured strain FBCC-A1260 .

Reference strain: FBCC-A 1260.

Additional strains: FBCC-A 1263, FBCC-A 1264, FBCC-A 1265.

Type locality: Iui-dong , Yeongtong-gu, Suwon-si, Gyeonggi-do, Korea (37°18’17.5”N; 127°02’03.4”E) ( Fig. 1 ).

Habitat: On the moist soil under the rock in Mt. Gwanggyo.

Gene sequences: 16S rRNA, 16S–23S ITS, and 23S rRNA gene sequences with GenBank accession numbers of MW 880693 to MW 880696 .

Figures

FIGURE 1. Map showing site in the Mt. Gwanggyo, Republic of Korea. (A) The aerial view (A red circle is collection site), (B) The habitat of a collection site.

FIGURE 2. Microphotographs of Porphyrosiphon annulatus the raw (A–C) and culture samples (D–J) from the reference strain (FBCC- A260). (A–B) Yellowish-brown and blue-green filaments, (C) Transversely annular lamellations in the sheath (arrow), (D) Colony of trichomes (sheath initially colorless and later yellow-brown or pink), (E, F) Longitudinal lamellations in the sheath (arrow), (G–I) Transversely annular lamellations in the sheath (arrows), (J) Two trichomes within a sheath; Scale bars = (A–C, E–J) 10 µm, (D) 50 µm.