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Myrionema expansum J.Agardh

Empire Eukaryota
Kingdom Chromista
Phylum Ochrophyta
Class Phaeophyceae
Subclass Fucophycidae
Order Ectocarpales
Family Chordariaceae
Genus Myrionema


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Myrionema expansum J.Agardh
James Price Point, Western Australia. J.M. Huisman. © J.M. Huisman.

Myrionema expansum J.Agardh
KwaZulu-Natal. Olivier de Clerck. © Olivier De Clerck (odclerck@gmail.com).


Batrachospermum diatyches Entwisle

Neoralfsia expansa (J.Agardh) P.-E.Lim & H.Kawai ex Cormaci & G.Furnari James Price Point, Western Australia
© J.M. Huisman

Publication details
Myrionema expansum J.Agardh 1847: 7

Published in: Agardh, J.G. (1847). Nya alger från Mexico. Öfversigt af Kongl. Vetenskaps-Adademiens Förhandlingar, Stockholm 4: 5-17.
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Type species
The type species (holotype) of the genus Myrionema is Myrionema strangulans Greville.

Status of name
This name is currently regarded as a synonym of Neoralfsia expansa (J.Agardh) P.-E.Lim & H.Kawai ex Cormaci & G.Furnari

Origin of species name
Participle A (Latin), expanded, spread out (Stearn 1973).

No synonyms are currently included in AlgaeBase.

Taxonomic notes
According to Leon-Alvarez & González-González (2003:613), the holotype of ... Ralsia expansa (J. Agardh) J. Agardh [Agardh 1847, as Myrionema(?) expansum] ... was sterile, and an incomplete description of the taxon was published by Agardh in 1848. Two subsequent studies described the species and included the reproductive structures: Borgesen (1912) and Tanaka & Chihara (1980a). However, these descriptions differ from one another and may indicate different species. Leon-Alvarez & González-González (2003:613, 620) conclude that specimens of Ralfsia expansa sensu Tanaka & Chihara (1980a), described in previous reports from the Pacific coast of Mexico, are actually R. hancockii. They consider R. expansa sensu Borgesen to be a distinct species, typically found on the tropical Atlantic coast. Lim et al. (2007: 464) cite Myrionema expansum J. Agardh 1848:7 as basionym of Neoralfsia expansa (J. Agardh) Lim & Kawai 2007.

General environment
This is a marine species.

Type information
Type locality: Veracruz, Mexico (Silva, Basson & Moe 1996: 573). Type: C (Yoshida 1998 Notes: According to Leon-Alvarez & González- González (2003: 613), the holotype of Ralfsia expansa (J. Agardh) J. Agardh [Agardh 1847, as Myrionema (?) expansum] was collected by Liebman from an unspecified area on the east coast of Mexico in Veracruz. The type specimen was sterile and an incomplete description of the taxon was published by Agardh in 1848.

Detailed distribution with sources (Click to Load)

Source of current name
Cormaci, M., Furnari, G., Catra, M., Alongi, G. & Giaccone, G. (2012). Erratum. Flora marina bentonica del Mediterraneo: Phaeophyceae. Bollettino dell'Accademia Gioenia 45: 509-510.

Key references
León-Alvarez, D. & González-González, J. (2003). The morphological distinction of Ralfsia expansa and R. hancockii (Ralfsiaceae, Phaeophyta) from Mexico. Phycologia 42: 613-621.

León-Álvarez, D., Núñez-Resendiz, M.L. & Wynne, M.J. (2014). Morphological and molecular studies on topotype material of Neoralfsia expansa (Phaeophyceae) reveal that Asian specimens assigned to this taxon are genetically distinct. Botanica Marina 57(5): 351-358.

Lim, P.-E., Sakaguchi, M., Hanyuda, T., Kogame, K., Phang, S.-M. & Kawai, H. (2007). Molecular phylogeny of crustose brown algae (Ralfsiales, Phaeophyceae) inferred from rbcL sequences resulting in the proposal for Neoralfsiaceae fam. nov.. Phycologia 46(4): 456-466, 1 fig, 3 tables.

Created: 31 July 1999 by M.D. Guiry

Verified by: 13 February 2015 by Wendy Guiry

Accesses: This record has been accessed by users 501 times since it was created.

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Linking to this page: http://www.algaebase.org/search/species/detail/?species_id=19522

Citing AlgaeBase
Cite this record as:
Wendy Guiry in Guiry, M.D. & Guiry, G.M. 2020. AlgaeBase. World-wide electronic publication, National University of Ireland, Galway. http://www.algaebase.org; searched on 27 February 2020.

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