Molecular systematics of Jania species (Corallinales, Rhodophyta) from south-eastern Australia based on cox 1 and psbA DNA sequence analyses Author Macagnan, Leonardo B. Universidade Federal de Santa Catarina, Centro de Cie ̂ ncias Biolo ́ gicas, Departamento de Bota ̂ nica, Floriano ́ polis, SC 88040 - 900, Brazil Author Venturin, Claudia S. Universidade Federal de Santa Catarina, Centro de Cie ̂ ncias Biolo ́ gicas, Departamento de Bota ̂ nica, Floriano ́ polis, SC 88040 - 900, Brazil Author Azevedo, Marina L. Universidade Federal de Santa Catarina, Centro de Cie ̂ ncias Biolo ́ gicas, Departamento de Bota ̂ nica, Floriano ́ polis, SC 88040 - 900, Brazil Author Harvey, Adela La Trobe University, Department of Environment and Genetics, Plenty Road, Bundoora, Vic. 3083, Australia Author Gurgel, C. Frederico D. Universidade Federal do Rio de Janeiro, Instituto de Biodiversidade e Sustentabilidade - NUPEM, Macaé, RJ 27965 - 045, Brazil & Former address: The University of Adelaide, School of Biological Sciences, Adelaide SA 5000, Australia; State Herbarium of South Australia, Department for Environment and Water, SA Government, PO Box 2732, Kent Town, SA 5071, Australia; & SARDI Aquatic Sciences, Department of Primary Industries & Regions, SA Government, PO Box 120, Henley Beach SA 5022, Australia. Corresponding author: fredgurgel @ nupem. ufrj. br text Phytotaxa 2023 2023-07-28 606 2 87 103 http://dx.doi.org/10.11646/phytotaxa.606.2.1 journal article 10.11646/phytotaxa.606.2.1 1179-3163 8202610 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 LTB 18250) reported here together with GenBank psb A sequences MH 017051 and MH 017052 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 ( MH 017053), 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.