<p><strong>Morphological and molecular investigation of freshwater <em>Hildenbrandia</em> (Hildenbrandiales, Rhodophyta) with a new species reported from Japan</strong></p>

Abstract

The morphological characterization and phylogenetic analysis based on molecular methods were executed on the freshwater Hildenbrandia specimens collected in this study. The cell size and filament height of the specimen collected from Pipa Lake, Japan were larger than the widely recognized species Hildenbrandia angolensis and Hildenbrandia rivularis, whereas overlapped with Hildenbrandia jigongshanensis. Based on molecular evidences of rbcL phylogenetic analysis and comparison of ITS1 secondary structure, specimen collected from Shiga Prefecture, Japan was proposed as a new species Hildenbrandia japananense. It brings the freshwater Hildenbrandia species in Japan to two. The specimens collected from Niangziguan, Shanxi province, China represent two new records of H. jigongshanensis. It enriches the species diversity of genus Hildenbrandia and increases the distribution diversity of this freshwater red algal taxon.

Substratum‐associated microbiota

“…Schneider and Wynne (2019) add 58 new genera and several new taxa as a part of the addendum to Schneider and Wynne's 2007 “A synoptic review of the classification of red algal genera a half century after Kylin's 1956 'Die Gattungen der Rhodophyceen.” Hildenbrandia japananense F.Nan et al sp. nov., described from specimens collected from Pipa Lake, Japan, along with new records of H. jigongshanensis documented from Shanxi province, China, add to the diversity of the global flora of Rhodophyta (Nan et al, 2019). Documentation of seven genera and nine species within the Batrachospermales from 30 stream reaches in South Carolina, United States, added to the known flora of this region (Redmond, Hollingsworth, & Vis, 2019).…”

Hildenbrandia (Hildenbrandiales, Florideophyceae) from Japan and taxonomic lumping of H. jigongshanensis and H. japananensis

“…(Japan) (as H. japananense in Nan et al . 2019), H. jigongshanensis F.Nan et al . (China), H. ramanaginae M.Khan (India) and H. rivularis (Liebmann) J.Agardh (widespread in Europe) (Guiry & Guiry 2020).…”

“…Hildenbrandia japananensis and H. jigongshanensis were only recently described based on morphological characterization and molecular data of rbc L DNA sequence, as well as secondary structure of rDNA ITS1 for H. japananensis and 18S rDNA for H. jigongshanensis (Nan et al . 2019), and are the only species for which type material was sequenced. Sequence data are publicly available for four of the six currently described freshwater species: H. angolensis , H. rivularis , H. japananensis and H. jigongshanensis .…”

“…1977; Kumano 2002; Kitayama 2014) and H. japananensis (Nan et al . 2019). The only molecular work done on Japanese Hildenbrandia was performed on H. japananensis (Nan et al .…”

“…The only molecular work done on Japanese Hildenbrandia was performed on H. japananensis (Nan et al . 2019) based on the specimens from a trout aquaculture farm (Samegai Trout Farm, Kaminyu, Maibara, Shiga Prefecture, Japan, upper stream of river flowing to Lake Biwa; incorrectly referred to as Lake Biwa (misspelled Lake Pipa) in Nan et al . (2019) abstract).…”