Fluvioralfsia iberica gen. et sp. nov., Fluvioralfsiaceae fam. nov.: The first freshwater member of the Ralfsiales (Phaeophyceae), collected from streams in Spain.
Andrés Mellado-Díaz, José Luis Moreno, María Verdugo-Althöfer, John D Wehr, Gary W Saunders
{"title":"Fluvioralfsia iberica gen. et sp. nov., Fluvioralfsiaceae fam. nov.: The first freshwater member of the Ralfsiales (Phaeophyceae), collected from streams in Spain.","authors":"Andrés Mellado-Díaz, José Luis Moreno, María Verdugo-Althöfer, John D Wehr, Gary W Saunders","doi":"10.1111/jpy.70022","DOIUrl":null,"url":null,"abstract":"<p><p>A novel brown alga inhabiting freshwater streams in Spain is described herein as Fluvioralfsia iberica gen. et sp. nov. Phylogenetic analyses establish it as a novel lineage within the Ralfsiales, Fluvioralfsiaceae fam. nov. It is an epilithic crust, typically orbicular with a radial growth pattern, formed by dichotomous fan-like branching of filaments. Crusts show a bilateral symmetry with horizontal medial filaments that bend upward and downward to form circular or semilunar protrusions in concentric bands that overlap at different levels. Older crusts are easily seen with the naked eye, becoming greater than 50 cm in diameter and 1 cm thickness and can cover a high percentage of the stream bottom in optimal habitats. Differentiating characters from other families of Ralfsiales include the absence of phaeophycean hairs and plurangia and, most notably, the unangia originating intercalarily from lower cells of paraphyses. Most populations were located in first- to third-order calcareous streams and rivers, at altitudes of 14-870 m.a.s.l., in the mountainous Cantabrian coast, northern Spain, and one river in southeast Spain. Sites were entirely nonmarine, 2-118 km from the sea, with median conductance of 219 μS · cm<sup>-1</sup> (range 112-859) in well-oxygenated, oligo-mesotrophic waters and moderate to high current velocities. As freshwater brown algae are a species-poor group, Fluvioralfsia iberica represents an important addition to the global freshwater algal flora and raises additional questions about the origins of phaeophytes in fresh waters.</p>","PeriodicalId":16831,"journal":{"name":"Journal of Phycology","volume":" ","pages":""},"PeriodicalIF":2.8000,"publicationDate":"2025-04-29","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":"0","resultStr":null,"platform":"Semanticscholar","paperid":null,"PeriodicalName":"Journal of Phycology","FirstCategoryId":"99","ListUrlMain":"https://doi.org/10.1111/jpy.70022","RegionNum":3,"RegionCategory":"生物学","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":null,"EPubDate":"","PubModel":"","JCR":"Q1","JCRName":"MARINE & FRESHWATER BIOLOGY","Score":null,"Total":0}
引用次数: 0
Abstract
A novel brown alga inhabiting freshwater streams in Spain is described herein as Fluvioralfsia iberica gen. et sp. nov. Phylogenetic analyses establish it as a novel lineage within the Ralfsiales, Fluvioralfsiaceae fam. nov. It is an epilithic crust, typically orbicular with a radial growth pattern, formed by dichotomous fan-like branching of filaments. Crusts show a bilateral symmetry with horizontal medial filaments that bend upward and downward to form circular or semilunar protrusions in concentric bands that overlap at different levels. Older crusts are easily seen with the naked eye, becoming greater than 50 cm in diameter and 1 cm thickness and can cover a high percentage of the stream bottom in optimal habitats. Differentiating characters from other families of Ralfsiales include the absence of phaeophycean hairs and plurangia and, most notably, the unangia originating intercalarily from lower cells of paraphyses. Most populations were located in first- to third-order calcareous streams and rivers, at altitudes of 14-870 m.a.s.l., in the mountainous Cantabrian coast, northern Spain, and one river in southeast Spain. Sites were entirely nonmarine, 2-118 km from the sea, with median conductance of 219 μS · cm-1 (range 112-859) in well-oxygenated, oligo-mesotrophic waters and moderate to high current velocities. As freshwater brown algae are a species-poor group, Fluvioralfsia iberica represents an important addition to the global freshwater algal flora and raises additional questions about the origins of phaeophytes in fresh waters.
期刊介绍:
The Journal of Phycology was founded in 1965 by the Phycological Society of America. All aspects of basic and applied research on algae are included to provide a common medium for the ecologist, physiologist, cell biologist, molecular biologist, morphologist, oceanographer, taxonomist, geneticist, and biochemist. The Journal also welcomes research that emphasizes algal interactions with other organisms and the roles of algae as components of natural ecosystems.
All aspects of basic and applied research on algae are included to provide a common medium for the ecologist, physiologist, cell biologist, molecular biologist, morphologist, oceanographer, acquaculturist, systematist, geneticist, and biochemist. The Journal also welcomes research that emphasizes algal interactions with other organisms and the roles of algae as components of natural ecosystems.