Porphyrosiphon annulatus sp. nov. (Oscillatoriales, Cyanobacteria) isolated on moist soil in Suwon, Republic of Korea Author Kim, Do-Hyun 0000-0002-2075-143X kim 7474747 @ naver. com; https: // orcid. org / 0000 - 0002 - 2075 - 143 X kim7474747@naver.com Author Lee, Nam-Ju 0000-0002-2403-1763 njlee @ kyonggi. ac. kr; https: // orcid. org / 0000 - 0002 - 2403 - 1763 njlee@kyonggi.ac.kr Author Yoon, Sung-Ro 0000-0002-3836-0760 charm 942 @ naver. com; https: // orcid. org / 0000 - 0002 - 3836 - 0760 charm942@naver.com Author Kim, Taehee 0000-0002-3203-1165 Department of Biotechnology, Sangmyung University, Seoul 03016, Republic of Korea & xogml 105 @ gmail. com; https: // orcid. org / 0000 - 0002 - 3203 - 1165 xogml105@gmail.com Author Ki, Jang-Seu 0000-0002-6007-9262 Department of Biotechnology, Sangmyung University, Seoul 03016, Republic of Korea & kijs @ smu. ac. kr; https: // orcid. org / 0000 - 0002 - 6007 - 9262 kijs@smu.ac.kr Author Lee, Ok-Min 0000-0003-3313-389X omlee @ kyonggi. ac. kr; https: // orcid. org / 0000 - 0003 - 3313 - 389 X omlee@kyonggi.ac.kr text Phytotaxa 2022 2022-02-02 532 3 288 300 journal article 20834 10.11646/phytotaxa.532.3.6 78a4ba4e-9873-4489-92f8-9cf970f26a0d 1179-3163 5964718 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 .