163,373 species and infraspecific names are in the database, 22,769 images, 62,949 bibliographic items, 480,226 distributional records.

Ralfsia expansa (J.Agardh) J.Agardh 1848

Empire Eukaryota
Kingdom Chromista
Phylum Ochrophyta
Class Phaeophyceae
Subclass Fucophycidae
Order Ralfsiales
Family Ralfsiaceae
Genus Ralfsia


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Ralfsia expansa (J.Agardh) J.Agardh
James Price Point, Western Australia. J.M. Huisman. © J.M. Huisman.

Ralfsia expansa (J.Agardh) 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
Ralfsia expansa (J.Agardh) J.Agardh 1848: 63

Published in: Agardh, J.G. (1848). Species genera et ordines algarum, seu descriptiones succinctae specierum, generum et ordinum, quibus algarum regnum constituitur. Volumen Primum. Algas fucoideas complectens. pp. [i-vi], [i]-viii, [1]-363. Lundae [Lund]: C.W.K. Gleerup.
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Type species
The type species (holotype) of the genus Ralfsia is Ralfsia deusta (C.Agardh) Berkeley.

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

Myrionema expansum J.Agardh

Type information
Type locality: Veracruz, Mexico (Silva & al. 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.

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

No synonyms are currently included in AlgaeBase.

Taxonomic notes
Close to Stragularia clavata (Fletcher 1987, p. 243). According to Leon-Alvarez & González-González (2003:613), an incomplete description of the taxon was published by Agardh in 1948. 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.

General environment
This is a marine species.

Detailed distribution with sources (Click to Load)

Source of current name
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.

Key references
Dawes, C.J. & Mathieson, A.C. (2008). The seaweeds of Florida. pp. [i]- viii, [1]-591, [592], pls I-LI. Gainesville, Florida: University Press of Florida.

De Toni, G.B. (1895). Sylloge algarum omnium hucusque cognitarum. Vol. III. Fucoideae. Vol. 3 pp. [i]-xvi, [1]-638. Patavii [Padua]: Sumptibus auctoris.

Huisman, J.M., Abbott, I.A., Smith, C.M. (2007). Hawaiian reef plants. pp. [1]-264, numerous colour photographs. Honolulu: A publication of the University of Hawai'i Sea Grant College Program.

Luan Rixiao, Ding Lanping, Lu Baoren & Tseng, C.K. (2013). Flora algarum marinarum sinicarum Tomus III Phaeophyta No. I(1) Ectocarpales Ralfsiales Sphaceariales Dictyotales. pp. [i]-xxii, 1-195, pls I-XXII. Beijing: Science Press. [in Chinese]

Skelton, P.A. & South, G.R. (2007). The benthic marine algae of the Samoan Archipelago, South Pacific, with emphasis on the Apia District. Nova Hedwigia Beihefte 132: 1-350.

Created: 10 December 1997 by M.D. Guiry

Verified by: 04 September 2015 by M.D. Guiry

Accesses: This record has been accessed by users 2033 times since it was created.

Verification of data
Users are responsible for verifying the accuracy of information before use, as noted on the website Content page.

(Please note: only references with the binomials in the title are included. The information is from the Literature database.)

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-Alvarez, D. (2005). The morphology of Ralfsia expansa (J. Agardh) J. Agardh (Ralfsiaceae, Phaeophyta) from Veracruz, Mexico. Cryptogamie Algologie 26: 343-354.
Sartoni, G. & Roddi, S. (1989). Acrospongium ralfsioides Schiffner and Ralfsia expansa (J. Agardh) J. Agardh (Ralfsiaceae, Phaeophyta): two new records from the Alboran Sea. Giornale Botanico Italiano 123: 145-155.
Tórgo, F.M.S. (1963). Observações sobre Ralfsia expansa (Phaeophyceae) e Hyella caespitosa (Cyanophyceae). Bolm Mus. nac. Rio de J.: nov. sér, bot., 30: 1-11, fig. 1-18, 1 mapa.
Tórgo, F.M.S. (1964). Observações sobre Ralfsia expansa (Phaeophyceae) e Hyella caespitosa (Cyanophyceae). : Anais XIII Congr. Soc. bot. Brasil, Recife. p. 107-113, fig. 1-18.

Linking to this page: http://www.algaebase.org/search/species/detail/?species_id=1271

Citing AlgaeBase
Cite this record as:
M.D. Guiry in Guiry, M.D. & Guiry, G.M. 2021. AlgaeBase. World-wide electronic publication, National University of Ireland, Galway. http://www.algaebase.org; searched on 23 September 2021.

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