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Comparison of six selected diagnostic characters between the (i) Polysiphonia, (ii) multipericentral, and (iii) Neosiphonia groups. A, number of pericentral cells (numbered circles)(character 10) and presence or absence of cortication (smaller circles peripheral to pericentral cells)(character 14); B, connection between rhizoids and pericentral cells open or with a crosswall (character 15); C, carpogonial branch three or four-celled (character 18); D, spermatangial axes development (character 22); and E, straight or spiral arrangement of tetrasporangia (tetrahedrally divided circles)(character 24). a, Boergeseniella is corticated; b, open or rarely separated by a crosswall in Vertebrata lanosa; c, on both the trichoblasts and trichoblast initials in P. fucoides, and on trichoblast initials in Vertebrata lanosa; d, cortication absent in N. savatieri, P. virgata has more than four pericentral cells; e, not known for P. elongata and P. virgata of this group; f, except P. virgata (straight series).
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The aim of this study was to reassess monophyly of the genus Polysiphonia and determine the phylogenetic affinities of its component lineages among related red algae belonging to the Rhodomelaceae. Our "total evidence" approach, combining 28 anatomical characters and small-subunit ribosomal DNA sequence data for 25 ceramialean algae including 14 sp...
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... According to current taxonomy (Guiry and Guiry 2021) this genus is placed in the family Rhodomelaceae, order Ceramiales, class Florideophyceae, and phylum Rhodophyta (red algae). After the reestablishment of the genus in 1967 (Christensen 1967), a series of phylogenetic studies, considering both anatomical and molecular data, was carried out to clarify the list of Vertebrata species (Choi et al. 2001;Díaz-Tapia et al. 2017a, b;Savoie and Saunders 2019). As a result, the genus Vertebrata was substantially expanded and acknowledged to be highly supported in phylogenetic analyses. ...
The red algal genus Vertebrata (Ceramiales, Rhodophyta) comprises 30 species of rather small filamentous algae, differing in morphology, distribution, and ecological preferences. In this review we focus on the two most studied Vertebrata species, V. lanosa and V. fucoides. These occur predominantly in cold and temperate waters on the North Atlantic coasts. Both species have recently gained attention due to their specific secondary metabolites, having considerable pharmaceutical potential and also due to their high capacity to accumulate heavy metals and radionuclides. The review summarizes the data on taxonomy, anatomy, cytology, genetics, ecology, distribution, and potential practical application of Vertebrata species. Special emphasis is on the biochemical composition of V. lanosa and V. fucoides, including their specific metabolites, such as bromophenols, organosulfur compounds, and mycosporine-like amino acids. In addition, the biochemistry and ecology of V. lanosa is discussed in the context of its increasing popularity as a spice (“sea truffle”) in several world cuisines.
... The placement of Stichothamnion in the Vertebrata clade is in agreement with the morphological characters proposed for the delineation of the genus Vertebrata, including the synapomorphic character of multinucleate trichoblasts (Díaz-Tapia et al., 2017b). Having more than five pericentral cells is another uniform character in Vertebrata and is also observed in the Stichothamnion lineage (Choi et al., 2001;Díaz-Tapia et al., 2017b). By contrast, spermatangial branches replacing trichoblasts in the Stichothamnion lineage is unusual in Vertebrata, and most species form spermatangia on one of the trichoblast branches (Díaz-Tapia et al., 2017b). ...
Algal turfs are ecosystem engineers receiving steadily growing attention in recent years in relation to their expansion on temperate reefs due to global change. However, their species diversity and taxonomy are still poorly understood, mostly based solely on morphological information. Algal turfs are the dominant type of assemblage in Macaronesia, but molecular diversity surveys have barely been applied in this region. We aim to show how molecular tools can assist us to improve our understanding of the diversity and taxonomy of natural algal turfs by studying the turf-forming rhodomelacean genus Stichothamnion which has only one recognized species in Macaronesia, the generitype S. cymatophilum. Stichothamnion resembles other members of the tribe Streblocladieae, but it has unbranched trichoblasts, an unusual character in the family. Here, we show using phylogenetic analyses of the rbcL gene that specimens collected in the Canary Islands and the Azores identifiable morphologically as S. cymatophilum exhibit cryptic diversity, and these analyses position Stichothamnion in the Vertebrata clade with full support. We place Stichothamnion in synonymy with Vertebrata, transfer the existing species, and describe a newly discovered cryptic species as V. barbarae Muñoz-Luque & Díaz-Tapia, sp. nov., found exclusively in the Azores. The new species was morphologically indistinguishable from V. cymatophila but diverged by 2.1-2.3% in the rbcL gene. This study illustrates the work required to better understand the extraordinary species diversity in algal turfs such as those in Macaronesia which remain taxonomically under-studied.
... Initial phylogenetic analyses of Polysiphonia resolved this genus as comprised of three distinct and well-supported lineages: the "Polysiphonia group," the "Neosiphonia group," and the "multipericentral group" (Choi et al. 2001). The "multipericentral group" initially included species of Boergeseniella, Enelittosiphonia, and Vertebrata, as well as several species of Polysiphonia with more than four pericentral cells (Choi et al. 2001). ...
... Initial phylogenetic analyses of Polysiphonia resolved this genus as comprised of three distinct and well-supported lineages: the "Polysiphonia group," the "Neosiphonia group," and the "multipericentral group" (Choi et al. 2001). The "multipericentral group" initially included species of Boergeseniella, Enelittosiphonia, and Vertebrata, as well as several species of Polysiphonia with more than four pericentral cells (Choi et al. 2001). Subsequently, the species of this group and others corresponding to Brongniartella, Ctenosiphonia, and Pterochondria were transferred to Vertebrata, the generic name with nomenclatural priority (D ıaz-Tapia et al. 2017b). ...
The recent segregation of 12 genera in the tribe Streblocladieae suggests that the taxonomy of some species belonging to Polysiphonia sensu lato is updated with the transfer and the proposal of new combinations. Accordingly, six new additions to the tribe Streblocladieae on the basis of morphological and molecular analyses are presented as a consequence of this new segregation. These additions include the description of the new species Carradoriella platensis sp. nov., the proposal of the following new combinations Eutrichosiphonia paniculata comb. nov., E. tapinocarpa comb. nov., and the reinstatement of Vertebrata curta, V. decipiens, and V. patersonis. Additionally, our morphological observations identified additional diagnostic features for two genera of the Streblocladieae. Carradoriella has branches with sexual reproductive structures arranged adaxially on branchlets, and the recently described Eutrichosiphonia has rhizoids with multicellular digitate haptera. Our study gives insights in regard to the distribution, the diagnostic features for delimiting genera morphologically, and the molecular evolutionary relationships in the Streblocladieae.
... It is the largest genus of red algae, including approximately 200 species worldwide, which are widely distributed, as well as morphologically and ecologically diverse (Maggs & Hommersand, 1993;Guiry & Guiry, 2018). This diversity, combined with its convoluted nomenclatural history, renders Polysiphonia an especially difficult genus for taxonomic and phylogenetic research (Kim et al., 2000;Choi et al., 2001). ...
... Kylin (1956) and Christensen (1967) both recognized the genus Vertebrata, for V. lanosa (Linnaeus) T.A.Christensen, as distinct from Polysiphonia. However, the segregation of V. lanosa from Polysiphonia was not widely accepted until Choi et al. (2001) presented molecular evidence to support recognition of this genus. ...
... Molecular tools such as DNA barcoding and phylogenetic analyses have been critical for resolving outstanding taxonomic issues in this difficult group. In one of the first published phylogenetic analyses to consider Polysiphonia, Choi et al. (2001) used nuclear small-subunit rDNA (SSU) sequence data to show that this genus was polyphyletic. In their analyses, Polysiphonia resolved as three well-supported lineages: the 'Polysiphonia group', which included the type species, P. stricta; the 'Neosiphonia group' which included species of Neosiphonia, as well as P. elongata (Hudson) Sprengel and P. virgata (C. ...
Sequence data generated during a Canadian barcode survey (COI-5P) of the tribes Polysiphonieae and Streblocladieae, a large and taxonomically challenging group of red algae, revealed significant taxonomic confusion and hidden species diversity. Polysiphonia pacifica Hollenberg, P. paniculata Montagne, P. stricta (Dillwyn) Greville and Vertebrata fucoides (Hudson) Kuntze were all complexes of two or more genetically distinct yet overlooked species. One variety of P. pacifica was elevated to the rank of species as P. determinata (Hollenberg) Savoie & Saunders, stat. nov. Several new additions to the Canadian flora were recorded including P. kapraunii Stuercke & Freshwater and P. morrowii Harvey. Subsequent multi-gene (COI-5P, LSU and rbcL) phylogenetic analyses confirmed that the genus Polysiphonia Greville was polyphyletic, and currently assigned species resolved with many other genera. Polysiphonia sensu stricto was restricted to a group of species that formed a monophyletic lineage with the type, Polysiphonia stricta. Carradoriella P.C.Silva was resurrected based on the South African species Carradoriella virgata (C.Agardh) P.C.Silva. Species previously attributed to Polysiphonia were transferred to Carradoriella, Leptosiphonia and Vertebrata as well as to three new genera described here: Acanthosiphonia gen. nov., based on A. echinata (Harvey) comb. nov.; Eutrichosiphonia gen. nov. for E. confusa (Hollenberg) comb. nov. and E. sabulosia (B.Kim & M.S.Kim) comb. nov.; and Kapraunia gen. nov., which includes K. schneideri (Stuercke & Freshwater) comb. nov. and three additional species.
... McIvor et al. (2001) found that "Neosiphonia simplex" in San Diego, California, had been incorrectly identified and was actually an introduced species, N. harveyi (J. Saunders, in Choi et al. (2001), which is now Melanothamnus harveyi (Bailey) Díaz-Tapia et . Gulf of California specimens identified as "N. ...
The present treatment constitutes an undated, annotated, systematic review of red, brown, and green benthic marine algae of the Gulf of California, Mexico, using the currently accepted taxon names, with the date and place of valid publication, type locality, and north to south distribution in the Gulf. The systematic list contains 730 species recognized in the Gulf of California, including 490 species of Rhodophyta, 112 species of Phaeophyceae, and 128 species of Chlorophyta. Among the previously recorded marine algae, 39 species are considered uncertain records or to have uncertain taxonomic status, the selection of a lectotype for Gracilaria hancockii resolves its taxonomic status, 3 combinations are made for recognized varieties of Caulerpa chemnitzia, and 15 species are excluded from the Gulf of California marine flora. The geographical distribution range of each species is given from its northernmost to southernmost locales within three regions the Gulf of California: the east coast of the Gulf (states of Sonora, Sinaloa, Nayarit, and northern Jalisco), the west coast of the Gulf (states of Baja California and Baja California Sur), the islands of the Gulf, including the Islas Grandes (=Islas de la Cintura; Midriff Islands), and islands of the states of Baja California, Baja California Sur, Sonora, Sinaloa, Nayarit, and northern Jalisco. Remarks, where appropriate, are included on taxonomy, nomenclature, ecology, and/or distribution with the taxon.
... McIvor et al. (2001) found that "Neosiphonia simplex" in San Diego, California, had been incorrectly identified and was actually an introduced species, N. harveyi (J. Saunders, in Choi et al. (2001), which is now Melanothamnus harveyi (Bailey) Díaz-Tapia et . Gulf of California specimens identified as "N. ...
The present treatment constitutes an undated, annotated, systematic review of red, brown, and green benthic marine algae of the Gulf of California, Mexico, using the currently accepted taxon names, with the date and place of valid publication, type locality, and north to south distribution in the Gulf. The systematic list contains 730 species recognized in the Gulf of California, including 490 species of Rhodophyta, 112 species of Phaeophyceae, and 128 species of Chlorophyta. Among the previously recorded marine algae, 39 species are considered uncertain records or to have uncertain taxonomic status, the selection of a lectotype for Gracilaria hancockii resolves its taxonomic status, 3 combinations are made for recognized varieties of Caulerpa chemnitzia, and 15 species are excluded from the Gulf of California marine flora. The geographical distribution range of each species is given from its northernmost to southernmost locales within three regions the Gulf of California: the east coast of the Gulf (states of Sonora, Sinaloa, Nayarit, and northern Jalisco), the west coast of the Gulf (states of Baja California and Baja California Sur), the islands of the Gulf, including the Islas Grandes (=Islas de la Cintura; Midriff Islands), and islands of the states of Baja California, Baja California Sur, Sonora, Sinaloa, Nayarit, and northern Jalisco. Remarks, where appropriate, are included on taxonomy, nomenclature, ecology, and/or distribution with the taxon.
... McIvor et al. (2001) found that "Neosiphonia simplex" in San Diego, California, had been incorrectly identified and was actually an introduced species, N. harveyi (J. Saunders, in Choi et al. (2001), which is now Melanothamnus harveyi (Bailey) Díaz-Tapia et . Gulf of California specimens identified as "N. ...
Norris, James N., Luis E. Aguilar-Rosas, and Francisco F. Pedroche. Conspectus of the Benthic Marine Algae of the Gulf of California: Rhodophyta, Phaeophyceae, and Chlorophyta. Smithsonian Contributions to Botany, number 106, vi +125 pages, 5 figures, 1 table, 1 appendix, 2017. — The present treatment constitutes an undated, annotated, systematic review of red, brown, and green benthic marine algae of the Gulf of California, Mexico, using the currently accepted taxon names, with the date and place of valid publication, type locality, and north to south distribution in the Gulf. The systematic list contains 730 species recognized in the Gulf of California, including 490 species of Rhodophyta, 112 species of Phaeophyceae, and 128 species of Chlorophyta. Among the previously recorded marine algae, 39 species are considered uncertain records or to have uncertain taxonomic status, the selection of a lectotype for Gracilaria hancockii resolves its taxonomic status, 3 combinations are made for recognized varieties of Caulerpa chemnitzia, and 15 species are excluded
from the Gulf of California marine flora. The geographical distribution range of each species is given from its northernmost to southernmost locales within three regions the Gulf of California: the east coast of the Gulf (states of Sonora, Sinaloa, Nayarit, and northern Jalisco), the west coast of the Gulf (states of Baja California and Baja California Sur), the islands of the Gulf, including the Islas Grandes (=Islas de la Cintura; Midriff Islands), and islands of the states of Baja California, Baja California Sur, Sonora, Sinaloa, Nayarit, and northern Jalisco. Remarks, where appropriate, are included on taxonomy, nomenclature, ecology, and/or distribution with the taxon .s m i t h s o n i a n c o n t r i b u t i o n s t o b o t a n y • n u m b e r 1 0 6
... Since the introduction of molecular tools for macroalgal systematics, some taxa of the Rhodomelaceae have been studied in attempts to clarify relationships among genera within the Polysiphonieae (Choi et al. 2001, D ıaz-Tapia et al. 2017b, Pterosiphonieae (Savoie and Saunders 2016), Bostrychieae (Zuccarello and West 2006), Laurencieae (Nam et al. 1994, Martin-Lescanne et al. 2010, Cassano et al. 2012, Metti et al. 2015, Mach ın-S anchez et al. 2016, Rousseau et al. 2017, Amansieae (Phillips 2002a,b, 2006, Phillips and De Clerck 2005, Heterocladieae and Pleurostichidieae (Phillips 2000). ...
... Two major lineages were resolved within this clade and we propose to segregate the tribe Streblocladieae from the Polysiphonieae. They are distinguished by the synapomorphic trait of having rhizoids cutoff from the mid-proximal end of the pericentral cells (Streblocladieae; Fig. 2A) versus rhizoids in open connection with the pericentral cells (Polysiphonieae; Fig. 2C; Kim and Lee 1999, Choi et al. 2001, D ıaz-Tapia et al. 2017b. ...
... The Polysiphonieae clade contains the type of the genus Polysiphonia (P. stricta) and it was termed Polysiphonia sensu stricto in previous phylogenetic studies of the tribe (Choi et al. 2001, D ıaz-Tapia et al. 2017b. These studies emphasized the existence of two major clades within Polysiphonia sensu stricto (here named Polysiphonia and Bryocladia/Falkenbergiella in Fig. S2), and they were resolved as monophyletic or paraphyletic in previous works depending on the taxon selection and the molecular marker(s) considered. ...
With over a thousand species, the Rhodomelaceae is the most species-rich family of red algae. While its genera have been assigned to 14 tribes, the high-level classification of the family has never been evaluated with a molecular phylogeny. Here, we reassess its classification by integrating genome-scale phylogenetic analysis with observations of the morphological characters of clades. In order to resolve relationships among the main lineages of the family we constructed a phylogeny with 55 chloroplast genomes (52 newly determined). The majority of branches were resolved with full bootstrap support. We then added 266 rbcL, 125 18S rRNA gene and 143 cox1 sequences to construct a comprehensive phylogeny containing nearly half of all known species in the family (407 species in 89 genera). These analyses suggest the same subdivision into higher-level lineages, but included many branches with moderate or poor support. The circumscription for nine of the 13 previously described tribes was supported, but the Lophothalieae, Polysiphonieae, Pterosiphonieae and Herposiphonieae required revision, and five new tribes and one resurrected tribe were segregated from them. Rhizoid anatomy is highlighted as a key diagnostic character for the morphological delineation of several lineages. This work provides the most extensive phylogenetic analysis of the Rhodomelaceae to date and successfully resolves the relationships among major clades of the family. Our data show that organellar genomes obtained through high-throughput sequencing produce well-resolved phylogenies of difficult groups, and their more general application in algal systematics will likely permit deciphering questions about classification at many taxonomic levels.
... The last overview of this symbiotic assemblage was by Garbary and Deckert (2001). Since then, there has been considerable research into this community, in particular dealing with the biology of the fungus, Mycophycias ascophylli, the association with the marine insect, Halocladius variabilis and the physiological ecology of Vertebrata lanosa (formerly Polysiphonia lanosa, see Choi et al., 2001). In this chapter we review the obligate and facultative symbionts that are part of the Ascophyllum community. ...
Ascophyllum nodosum provides the ultimate host for a symbiotic community of diverse eukaryotes comprising two brown algae (Ascophyllum nodosum, Elachista fucicola), two red algae (Vertebrata lanosa, Choreocolax polysiphoniae), a fungus (Mycophycias ascophylli), an insect (Halocladius variabilis), and a diatom (Navicula endophytica). The interactions of these symbionts vary from apparent mutualists (i.e., Ascophyllum–Mycophycias, Elachista–Halocladius) to obligate or facultative parasites (Choreocolax–Vertebrata, Elachista–Ascophyllum), with several interactions being either commensal (Ascophyllum–Vertebrata), or as yet uncharacterized (Navicula–Ascophyllum, Mycophycias– Vertebrata). The facultative nature of some of the associations suggests that the community may still be evolving host specificity. In addition, the components of the symbiotic community vary geographically and ecologically. In this chapter, we review the interactions of these species from ecological, physiological, and ultrastructural perspectives.
... Hommersand (1963) and Norris (1994) compared Fernandosiphonia (trichoblasts formed spirally) with Streblocladia (trichoblasts borne only adaxially). Choi et al. (2001) drew attention to the relationship in their 18S tree between N. japonica and Polysiphonia virgata, the type species of Carradoriella P.C.Silva (Kylin, 1956, as Carradoria;Silva et al., 1996), and suggested that Neosiphonia might either be subsumed into Carradoriella or be resolved as a sister to it. Recent searches of DNA sequence databases unexpectedly showed a possible relationship between Neosiphonia species and Melanothamnus somalensis, the type species of the genus Melanothamnus Bornet & Falkenberg, which was regarded as incertae sedis (Falkenberg, 1901). ...
... We conclude from molecular and morphological evidence that members of this clade represent a single genus. Vertebrata is the oldest name among those available for this clade, as noted before (Choi et al., 2001), and the new combinations proposed in Table 2 are required. Furthermore, the Vertebrata binomials previously established by Kuntze (1891) should be reinstated for the other 13 species included in this clade (Table 3). ...
Polysiphonia is the largest genus of red algae, and several schemes subdividing it into smaller taxa have been proposed since its original description. Most of these proposals were not generally accepted, and currently the tribe Polysiphonieae consists of the large genus Polysiphonia (190 species), the segregate genus Neosiphonia (43 species) and 13 smaller genera (< 10 species each). In this paper, phylogenetic relationships of the tribe Polysiphonieae are analysed, with particular emphasis on the genera Carradoriella, Fernandosiphonia, Melanothamnus, Neosiphonia, Polysiphonia sensu stricto, Streblocladia and Vertebrata. We evaluated the consistency of 14 selected morphological characters in the identified clades. Based on molecular phylogenetic (rbcL and 18S genes) and morphological evidence, two speciose genera are recognized: Vertebrata (including the type species of the genera Ctenosiphonia, Enelittosiphonia, Boergeseniella and Brongniartella) and Melanothamnus (including the type species of the genera Fernandosiphonia and Neosiphonia). Both genera are distinguished from other members of the Polysiphonieae by synapomorphic characters, the emergence of which could have provided evolutionarily selective advantages for these two lineages. In Vertebrata trichoblast cells are multinucleate, possibly associated with the development of extraordinarily long photoprotective trichoblasts. Melanothamnus has 3-celled carpogonial branches and plastids lying exclusively on radial walls of the pericentral cells, which similarly may improve resistance to damage caused by excessive light. Other relevant characters that are constant in each genus are also shared with other clades. The evolutionary origin of the genera Melanothamnus and Vertebrata is estimated as 75.7–95.78 and 90.7–138.66 Ma, respectively. Despite arising in the Cretaceous, before the closure of the Tethys Seaway, Melanothamnus is a predominantly Indo-Pacific genus and its near-absence from the north-eastern Atlantic is enigmatic. The nomenclatural implications of this work are that 46 species are here transferred to Melanothamnus, six species are transferred to Vertebrata, and 13 names are resurrected for Vertebrata.
