Reproductive morphology and <scp>DNA</scp> sequences of the brown alga Platysiphon verticillatus support the new combination Platysiphon glacialis

• Published in: Journal of Phycology
• Main Authors: Kawai, Hiroshi, Hanyuda, Takeaki, Yamagishi, Takahiro, Kai, Atsushi, Lane, Chris E., McDevit, Dan, Küpper, Frithjof C., Saunders, Gary W.
• Other Authors: Gabrielson, P., National Science Foundation, Natural Environment Research Council, Ontario Genomics Institute, Canada Foundation for Innovation, New Brunswick Innovation Foundation
• Format: Article in Journal/Newspaper
• Language: English
• Published: Wiley 2015
• Subjects: Plant Science; Aquatic Science; Arctic; Baffin Island; Greenland; Baffin
• Online Access: http://dx.doi.org/10.1111/jpy.12331; https://api.wiley.com/onlinelibrary/tdm/v1/articles/10.1111%2Fjpy.12331; https://onlinelibrary.wiley.com/doi/pdf/10.1111/jpy.12331; https://onlinelibrary.wiley.com/doi/full-xml/10.1111/jpy.12331

Platysiphon verticillatus , a brown alga endemic to the Arctic, was described based on vegetative specimens collected at Inglefield Bay, West Greenland. The species is distinctive in having a lanceolate blade‐like thallus terminated by a terete portion, both covered with hair‐like assimilatory filaments. Punctaria glacialis was described from Eastern Greenland, and the species differs from other Punctaria species in lacking hairs and plurilocular zoidangia. Unilocular zoidangia were reported, but instead of zoids being released they formed cell walls in situ developing the appearance of plurilocular zoidangia. However, the fate of the zoids, as well as the walled cells was not traced, and the life history of the alga has remained unclear. By comparing DNA sequences ( cox 1, cox 3, and rDNA ITS 2) of specimens morphologically referable to Platysiphon verticillatus and Punctaria glacialis collected at Baffin Island, as well as re‐examining morphology and studying crude cultures, we concluded that they are the same taxonomic entity. Furthermore, their cox 3 sequence and vegetative morphology agreed with those of the type specimen of Punctaria glacialis . Consequently, we propose Platysiphon glacialis comb. nov. The life cycle could not be completed in culture, but we hypothesize that in situ germination of the unizoids produces reduced gametophytes housed in peripheral tissue of erect sporophytic thalli.