Jania micrarthrodia J.V.Lamouroux

Macagnan, Leonardo B., Venturin, Claudia S., Azevedo, Marina L., Harvey, Adela & Gurgel, C. Frederico D., 2023, Molecular systematics of Jania species (Corallinales, Rhodophyta) from south-eastern Australia based on cox 1 and psbA DNA sequence analyses, Phytotaxa 606 (2), pp. 87-103 : 98

Jania micrarthrodia J.V.Lamouroux

— Jania micrarthrodia type locality is Australia, but the specific locality is debatable. Millar and Kraft (1993) suggested that the type locality is Port Philip Bay, Victoria, while Goldberg and Kendrick (2005) proposed the type locality to be the mouth of the Swan River, Western Australia. Both proposals lack supporting evidence according to Harvey et al. (2020). Jania micrarthrodia has been reported across temperate Australia, including Tasmania, and New Zealand ( Silva et al. 1996, Johansen and Womersley 1994). The specimens sequenced in this study are from Bittangabee Bay (South Australia) and Coffs Harbour (New South Wales). Harvey et al. (2020) concurred with Johansen and Womersley (1994) that J. micrarthrodia thallus morphology varies widely depending on which environmental conditions (e.g., water movement) the specimen is growing in. The new psb A sequence from Jania micrarthrodia (specimen LTB18250) reported here together with GenBank psb A sequences MH017051 and MH017052 from Victoria and New South Wales, respectively, resolved J. micrarthrodia as a single clade sister to J. sphaeroramosa (Figs 3,4). Intraspecific genetic divergences among Australian J. micrarthrodia psb A sequences varied between 0.0–2.2% (p-distances), which is within the range of psb A intraspecific divergences observed for other Jania species (e.g., J. crassa : 0.0–1.2%, Jania sagitatta : 0.0–0.81%). In our psb A phylogenetic and SDM results, a specimen originally identified as J. micrarthrodia by Twist et al. (2018) from Kangaroo Island, South Australia (MH017053), was resolved in the J. sphaeroramosa clade and shares a most recent common ancestor with all other J. sphaeroramosa from New Zealand. SDMs identified the Australian specimen as a distinct species from New Zealand populations, suggesting allopatric speciation.