Mychodea and the Mychodeaceae (Gigartinales, Rhodophyta) revisited: molecular analyses shed light on interspecies relationships in Australia’s largest endemic algal genus and family
Gerald T. Kraft A C and Gary W. Saunders BA School of Biosciences, University of Melbourne, Parkville, Vic. 3010, Australia.
B Department of Biology, University of New Brunswick, PO Box 4400, Fredericton, NB, E3B 5A3, Canada. Email: gws@unb.ca
C Corresponding author. Present address: Tasmanian Herbarium, College Road, Sandy Bay Tas. 7005, Australia. Email: gtk@unimelb.edu.au
Australian Systematic Botany 30(3) 230-258 https://doi.org/10.1071/SB16058
Submitted: 12 December 2016 Accepted: 7 July 2017 Published: 20 October 2017
Abstract
The red algal genus Mychodea Hook.f. & Harv. is not only Australia’s largest wholly endemic macroalgal genus, it and the family Mychodeaceae (of which it is the sole member) appear to be the largest completely endemic algal genus and family from any continental landmass in the world. Kraft’s 1978 morpho-taxonomic monograph credited Mychodea with 11 species varyingly distributed between Geraldton, Western Australia, south and eastward across the coasts of South Australia, Victoria and Tasmania, and northwards into southern New South Wales. Dismissed or discounted was every former extra-Australian attribution of the genus. In the over 40 years since completion of the research, further explorations of marine habitats in Australia have uncovered additional species, and the application of molecular-assisted taxonomic and phylogenetic methodologies has now allowed a substantial refinement of Mychodea systematics. We here document 19 Mychodea species, for 16 of which we have molecular data that support inferences of probable species relationships. To the 11 species treated by Kraft we now add 4 that are recently discovered, resurrect 2 that were synonymised with a third species in his 1978 work, and treat 2 species-level Western Australian entities that remain unnamed for lack of sufficient reproductive material. Mychodea is characterised by elaborate vegetative structures and some of the most complex fertilisation, diploidisation and embryogenesis processes of any red alga, which we detail and illustrate. Distinguishing features of the individual species are highlighted, some of which are particularly unusual.
Additional keywords: biogeography, macroalgae, molecular-assisted alpha taxonomy, morpho-taxonomy, phylogenetics.
References
Agardh JG (1872) Bidrag till florideernes systematik. Lunds Universitets Årsskrift, Afdeling for Mathematik och Naturvetenskap 8, 60Agardh JG (1876) ‘Species, Genera et Ordines Algarum. Vol. 3, Pt. 1. Epicrisis Systematis Floridearum.’ (Weigel: Leipzig, Germany)
Agardh JG (1879) Florideernes morphologie. Konglia Sveanska Veatenskaps-Akademiens Handligar – Ser. 4 15, 1–199.
Ardissone F (1888) Le alghe della Terra del Fuego racolte dal prof. Spegazzini. Rendiconti del Reale Istituto Lombardo di Scienze e Lettere – Ser. 2 21, 208–215.
Børgesen F (1943) Some marine algae from Mauritius. III. Rhodophyceae, pt. 2: Gelidiales, Cryptonemioales, Gigartinales. Det Kongliga Danske Videnskabernes Selskab – Biologiske Meddelelser 19, 1–85.
Hariot P (1892) Complément a la flore algologique de la Terre de Feu. Notarisia 7, 1427–1435.
Harvey WH (1860) ‘Phycologia Australica. Vol. 3.’ (Reeves: London, UK)
Harvey WH (1862) ‘Phycologia Australica. Vol. 4.’ (Reeves: London, UK)
Harvey WH (1863) ‘Phycologia Australica. Vol. 5.’ (Reeves: London, UK)
Hooker JD, Harvey WH (1847) Algae tasmanicae: being a catalogue of the species of algae collected on the shores of Tasmania by Ronald Gunn, Esq., Dr Heannerett, Mrs Smith, Dr Lyall and Dr J.D. Hooker; with characters of the new species. London Journal of Botany 6, 397–417.
Kraft GT (1974) Monograph of the Mychodeaceae, Dicranemaceae and Acrotylaceae (Gigartinales, Rhodophyta). PhD Thesis, University of Adelaide, SA, Australia.
Kraft GT (1978) Studies of marine algae in the lesser-known families of the Gigartinales (Rhodophyta). III. The Mychodeaceae and Mychodeophyllaceae. Australian Journal of Botany 26, 515–610.
| Studies of marine algae in the lesser-known families of the Gigartinales (Rhodophyta). III. The Mychodeaceae and Mychodeophyllaceae.Crossref | GoogleScholarGoogle Scholar |
Kraft GT, Saunders GW (2014) Crebradomus and Dissimularia, new genera in the family Chondrymeniaceae (Gigartinales, Rhodophyta) from the central, southern and western Pacific. Phycologia 53, 146–166.
| Crebradomus and Dissimularia, new genera in the family Chondrymeniaceae (Gigartinales, Rhodophyta) from the central, southern and western Pacific.Crossref | GoogleScholarGoogle Scholar |
Kraft GT, Womersley HBS (1994) Mychodeaceae. In ‘The Marine Benthic Flora of Southern Australia, Part IIIA’. (Ed. HBS Womersley) pp. 450–470. (Australian Biological Resources Study: Canberra, ACT, Australia)
Kützing FT (1859) ‘Tabulae phycologicae. Vol. 9.’ (F. Eberhardt: Nordhausen)
Kützing FT (1866) ‘Tabulae phycologicae. Vol. 16.’ (F. Eberhardt: Nordhausen)
Kylin H (1932) Die Florideenordnung Gigartinales. Acta Universitatis Lundensis 28, 1–88.
Kylin H (1956) ‘Die Gattungen der Rhodophyceen.’ (Gleerups: Lund, Sweden)
Millar AJK, Kraft GT (1993) Catalogue of marine and freshwater red algae (Rhodophyta) of New South Wales, including Lord Howe Island, South-western Pacific. Australian Systematic Botany 6, 1–90.
| Catalogue of marine and freshwater red algae (Rhodophyta) of New South Wales, including Lord Howe Island, South-western Pacific.Crossref | GoogleScholarGoogle Scholar |
Ramírez ME, Santelices B (1991) Catálogo de las algas marinas bentónicas de la costa temperada del Pacífico de Sudamérica. Monografías Biológicas 5, 1–437.
Saunders GW, McDevit DC (2012) Methods for DNA barcoding photosynthetic protists emphasizing the macroalgae and diatoms. Methods in Molecular Biology 858, 207–222.
| Methods for DNA barcoding photosynthetic protists emphasizing the macroalgae and diatoms.Crossref | GoogleScholarGoogle Scholar | 1:CAS:528:DC%2BC38XhvVWqu7bE&md5=aff64a9889122196d14a3f34225aeacfCAS |
Saunders GW, Moore TE (2013) Refinements for the amplification and sequencing of red algal DNA barcode and RedToL phylogenetic markers: a summary of current primers, profiles and strategies. Algae – Korean Phycological Society 28, 31–43.
| Refinements for the amplification and sequencing of red algal DNA barcode and RedToL phylogenetic markers: a summary of current primers, profiles and strategies.Crossref | GoogleScholarGoogle Scholar | 1:CAS:528:DC%2BC3sXntVagsbs%3D&md5=8a1316b91b6e73ffe4ccb21aae89e345CAS |
Saunders GW, Chiovitti A, Kraft GT (2004) Small-subunit rDNA sequences from representatives of selected families of the Gigartinales and Rhodymeniales (Rhodophyta). 3. Delineating the Gigartinales sensu stricto. Canadian Journal of Botany 82, 43–74.
| Small-subunit rDNA sequences from representatives of selected families of the Gigartinales and Rhodymeniales (Rhodophyta). 3. Delineating the Gigartinales sensu stricto.Crossref | GoogleScholarGoogle Scholar | 1:CAS:528:DC%2BD2cXjtFCqsro%3D&md5=e9ede18017c14f858567270a30878414CAS |
Schmitz F (1889) Systematische Ubersicht der bisher bekannten Gattungen der Florideen. Flora oder Allgemeine botanische Zeitung 72, 435–456.
Stamatakis A, Hoover P, Rougemont J (2008) A rapid bootstrap algorithm for the RAxML web-servers. Systematic Biology 57, 758–771.
| A rapid bootstrap algorithm for the RAxML web-servers.Crossref | GoogleScholarGoogle Scholar |
Watson JE (1973) Pearson Island Expedition 1969. 9. Hydroids. Transactions of the Royal Society of South Australia 97, 153–200.
Zanardini G (1874) Phycae Australicae novae et minus cognitae. Flora 57, 486–490, 497–505.
