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John A West - One of the best experts on this subject based on the ideXlab platform.
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analysis of chloroplast genomes and a supermatrix inform reclassification of the Rhodomelaceae rhodophyta
Journal of Phycology, 2017Co-Authors: Pilar Diaztapia, Christine A. Maggs, John A West, Heroen VerbruggenAbstract: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.
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evolution of four southern hemisphere bostrychia Rhodomelaceae rhodophyta species phylogeny species delimitation and divergence times
Phycologia, 2014Co-Authors: Narongrit Muangmai, John A West, Giuseppe C ZuccarelloAbstract:Abstract: Defining species boundaries is important to address evolutionary questions and understand true biodiversity in a region. Determining the actual number of species is not trivial, and numerous species-delimitation algorithms have been developed and extensively applied to a wide range of organisms. The cosmopolitan red-algal genus Bostrychia has been used as a model system to study evolutionary processes, yet phylogeny within the genus and its true species composition are still unresolved. The four species B. arbuscula, B. gracilis, B. intricata and B. vaga represented a distinctive morphotype that was once the basis for segregation into the separate genus Stictosiphonia, and all appeared to be restricted to the Southern Hemisphere. We sequenced genes from all three genomes [plastid: rbcL; mitochondrial: cytochrome c oxidase subunit I(COI); and nuclear: large-subunit ribosomal RNA] to examine the phylogenetic relationships of the four species and to establish their diacritical features. Our phyloge...
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monosiphonous growth and cell death in an unusual bostrychia Rhodomelaceae rhodophyta b anomala sp nov
Algae, 2013Co-Authors: John A West, Susan Loiseauxde Goer, Giuseppe C ZuccarelloAbstract:A morphologically distinct lineage within the Bostrychia moritziana-B. radicans species complex is described as a new species. Bostrychia anomala has thalli with branched monosiphonous filaments with apical cell divisions. The species has terminal tetrasporangial stichidia, each subtending cell bearing tetrasporangia with 2 cover cells. Discharged spores divide transversely, the lower cell first forming a narrow rhizoid and the upper cell forming a monosiphonous shoot. Females have subterminal procarps and males have terminal spermatangial stichidia. Carposporophytes are spherical. Isolates in culture show a pattern of cell death not associated with injury, reminiscent of programmed cell death. Bostrychia anomola shows cell death at intervals along the filaments resulting in division of adjacent cells on either side of the dead cell re-joining the filament; cell division of only one adjacent cell resulting in branching at that site; or filaments fragmenting at the cell death point with adjacent cells forming new apical cells, a means of thallus propagation. The cell death pattern could be a method of filament propagation in the mangrove environment where sexual reproduction is rare.
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gall structure and specificity in bostrychia culture isolates Rhodomelaceae rhodophyta
Algae, 2013Co-Authors: John A West, Curt M Pueschel, Tatyana A Klochkova, Gwang Hoon Kim, Susan Loiseaux De Goer, Giuseppe C ZuccarelloAbstract:The descriptions of galls, or tumors, in red algae have been sparse. Ktzing (1865) observed possible galls of Bostrychia but only presented a drawing. Intensive culture observations of hundreds of specimens of the genus Bostrychia over many years have revealed that galls appeared in only a small subset of our unialgal cultures of B. kelanensis, Bostrychia moritziana/radicans, B. radicosa, B. simpliciuscula, and B. tenella and continued to be produced intermittently or continuously over many years in some cultures but were never seen in field specimens. Galls appeared as unorganized tissue found primarily on males and bisexuals, but occasionally on females and tetrasporophytes. The gall cells usually were less pigmented than neighboring tissue, but contained cells with fluorescent plastids and nuclei. The galls were not transferable to other potential hosts. Galls could be produced from gall-free tissue of cultures that originally had galls even after transfer to new culture dishes. Electon microscopy of galls on one isolate (3895) showed that virus-like particles are observed in some gall cells. It is possible that a virus is the causative agent of these galls.
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bostrychia Rhodomelaceae rhodophyta species of new zealand and relationships in the southern hemisphere
New Zealand Journal of Marine and Freshwater Research, 2008Co-Authors: Giuseppe C Zuccarello, John A WestAbstract:Abstract Bostrychia is a widespread genus and has recently received considerable molecular attention, leading to insights into its evolution, and nomenclatural changes. We investigated the species of Bostrychia in New Zealand, to produce an identification key and highlight the nomenclatural changes of these species. We incorporated into a molecular phylogeny two species prominent in New Zealand (B. gracilis, B. vaga) that have not be investigated phylogenetically before. Our results show thatthree species of Bostrychia (B. arbuscula, B. gracilis, B. vaga), mainly restricted to New Zealand, share a common ancestor. Only B. vaga is known outside New Zealand. This restricted distribution is unusual for species within this genus in which many are widespread. A phylogeographic study of another New Zealand and Southern Hemisphere species, B. intricata, indicates that this species consists of several lineages that are found locally. These lineages, and physiological difference between lineages, suggest that cryp...
Myung-sook Kim - One of the best experts on this subject based on the ideXlab platform.
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morphology and molecular study of pterosiphonia arenosa sp nov Rhodomelaceae rhodophyta from jeju island korea
Algae, 2012Co-Authors: Myung-sook Kim, Su Yeon Kim, Mi Yeon Yang, Byeongseok Kim, Pilar DiaztapiaAbstract:The genus Pterosiphonia is composed of 22 species worldwide and four of these species have been reported in the North-East Asia. In Korea, P. pennata originally described from the Mediterranean Sea has been previously recorded from the southern coast as a widespread species. In order to confirm the same species from Korea and Mediterranean, we observed the morphology of Korean Pterosiphonia specimen and analyzed rbcL sequences for inferring phylogenetic relationships among similar congeners. Korean entity was recognized as a new species, Pterosiphonia arenosa sp. nov. The new species is characterized by ecorticate axes with 7-10 pericentral cells, branches formed every two segments, and coalesced with main axis over 1-1.25 axial segments, and tetrasporangia formed in straight series on determinate branches of the upper parts of erect axes. A phylogenetic analysis of rbcL sequences demonstrated that P. arenosa was distinct from P. pennata found in Spain as well as other species. In conclusion, morphological and molecular sequence data indicated that P. arenosa sp. nov. has been previously misidentified as P. pennata in Korea.
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a reappraisal of symphyocladia Rhodomelaceae rhodophyta including a new species based on morphology and molecular data
Phycologia, 2012Co-Authors: Su Yeon Kim, Wendy A Nelson, Myung-sook KimAbstract:Kim S.Y., Nelson W. and Kim M.S. 2012. A reappraisal of Symphyocladia (Rhodomelaceae, Rhodophyta), including a new species based on morphology and molecular data. Phycologia 51: 531–541. DOI: 10.2216/11-62.1 Comparative morphological investigations and molecular analyses of rbcL data are used to critically reassess the genus Symphyocladia and to examine phylogenetic relationships with the type species, S. marchantioides. Specimens collected from the type locality in New Zealand confirm that S. marchantioides can be identified by the presence of numerous apical cells on the growing margin producing axial systems that remain congenitally laterally attached, branched trichoblasts arising marginally and close to dormant apical cells, six to eight pericentral cells, and lacking cortication. Symphyocladia jejuinsula sp. nov is newly described for samples from the southern coast of Korea, and is characterized by thin and flat thalli to 10 cm in height, 8–10 pericentral cells, lack of trichoblasts, 10 segments of...
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a new red algal parasite symphyocolax koreana gen et sp nov Rhodomelaceae ceramiales from korea
Algae, 2010Co-Authors: Myung-sook Kim, Ga Youn ChoAbstract:A new red algal parasite, Symphyocolax koreana M. S. Kim, gen. et sp. nov., has been found on a specimen of Symphyocladia latiuscula (Harvey) Yamada, a member of the tribe Pterosiphonieae of the Rhodomelaceae; this genus has never before been reported to host red algal parasites. Here, the new parasite from Korea is described in terms of vegetative and reproductive morphology. The thallus has a minute, colored polysiphonous upright axis with many branches attached by pseudoparenchymatous pulvinate bases. There are six pericentral cells, with many corticated cells in the lower part of the main branches. Trichoblasts occur on dioecious male and female gametophytes, but not on tetrasporophytes. Procarps develop on suprabasal cells of trichoblasts and consist of a four-celled carpogonial branch and two sterile cells attached to the supporting cell. Spermatangial branches are borne one per each successive segment on monosiphonous pedicels in spiral positions with fertile trichoblast. Tetrasporangia are formed one per segment in a straight series and are tetrahedrally divided. Features of the vegetative axes, procarp, spermatangial trichoblasts, and tetrasporangial branching show that the new genus is an alloparasite belonging to the tribe Polysiphonieae.
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taxonomy and phylogeny of neosiphonia japonica Rhodomelaceae rhodophyta based on rbcl and cpea b gene sequences
Algae, 2006Co-Authors: Myung-sook Kim, Eunchang YangAbstract:Neosiphonia M.S. Kim et I.K. Lee is a rhodomelacean red algal genus that is commonly encountered in the intertidal zone of temperate waters in the world. The genus Neosiphonia, which was established based on species previously named under the genus Polysiphonia, is well distinguished by procarps bearing a three-celled carpogonial branches, spermatangial branches arising from a branch of the trichoblasts, and tetrasporangia arranged in spiral series (Kim and Lee 1999). The phylogenetic difference of Neosiphonia from Polysiphonia is clearly shown by both cladistic analyses of morphological features and phylogenetic analyses of nuclear ribosomal small subunit (SSU) region sequences (Choi et al. 2001). Recently, Neosiphonia is found in Malaysia (Masuda et al. 2001; Tani et al. 2003), Vietnam (Abbott et al. 2002), Brazil (Guimaraes et al. 2004), Hawaii (Kim and Abbott 2006), and Japan as well as Korea (Kim 2005). To date, 22 species previously placed in Polysiphonia have been transferred into Neosiphonia and 1 new species reported. Neosiphonia japonica (Harvey) M.S. Kim et I.K. Lee was originally described from Hakodate, Hokkaido, Japan, as Polysiphonia japonica by Harvey (1856). The species has a bush-like habit, four pericental cells, cortication on axes, numerous branches, and three-celled carpogonial branches on females. The thalli occur commonly as epiphytes on other seaweeds from Korea (Kim 1995), Japan (Yoshida 1998), China (Tseng 1984), and Pacific Russia (Perestenko 1994). Despite studies on the morphology (Yoon 1986; Kudo and Masuda 1986; Kim 1995), life history (Kudo and Masuda 1986), lectotypification (Masuda et al. 1995), and distribution (Kim 1995), the taxonomy of N. japonica is still problematic. Kudo and Masuda (1986) reported that N. japonica (as Polysiphonia japonica) is very similar to N. harlandii (Harvey) M.S. Kim et I.K. Lee, N. decumbens (Segi) M.S. Kim et I.K. Lee, and P. akkeshiensis Segi. Yoon (1986) also concluded N. savatieri (Hariot) M.S. Kim et I.K. Lee, P. forfex Harvey and N. teradomariensis (Noda) M.S. Kim et I.K. Lee as varieties of N. japonica, based on the number of pericentral cells and the presence or absence of cortication at the base. Recently, McIvor et al. (2001) proposed that N. japonica, together with P. akkeshiensis Segi, P. acuminata N.L. Gardner and P. strictissima J.D. Hooker & Harvey were conspecific with N. harveyi (J. Bailey) M.S. Kim, H.G. Choi, Guiry & Algae Volume 21(3): 287-294, 2006
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Taxonomic notes on Hawaiian Polysiphonia, with transfer to Neosiphonia (Rhodomelaceae, Rhodophyta)
Phycological Research, 2006Co-Authors: Myung-sook Kim, Isabella A. AbbottAbstract:SUMMARY After detailed observations of type material and other collections, five Hawaiian species of Polysiphonia Greville, nom. cons. are recognized to be species of Neosiphonia M. S. Kim et I. K. Lee; namely, Neosiphonia apiculata (Hollenberg) Masuda et Kogame, Neosiphonia beaudettei (Hollenberg) M. S. Kim et Abbott, comb. nov., Neosiphonia hawaiiensis (Hollenberg) M. S. Kim et Abbott, comb. nov., Neosiphonia profunda (Hollenberg) M. S. Kim et Abbott, comb. nov., and Neosiphonia rubrorhiza (Hollenberg) M. S. Kim et Abbott, comb. nov. These five species are ecorticate, having lateral branch initials and trichoblasts produced on successive segments, rhizoids separated from pericentral cells by a cross wall, three-celled carpogonial branches (not seen in N. beaudettei and N. rubrorhiza), spermatangial branches arising on a primary branch of the trichoblasts, and tetrasporangia in a spiral series. Although certain characters were not available for some species, all other characters occur in a combination that is unique for members of Neosiphonia.
Giuseppe C Zuccarello - One of the best experts on this subject based on the ideXlab platform.
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development of the red algal parasite vertebrata aterrimophila sp nov Rhodomelaceae ceramiales from new zealand
European Journal of Phycology, 2019Co-Authors: Maren Preuss, Giuseppe C ZuccarelloAbstract:© 2019, © 2019 British Phycological Society. Parasitic red algae grow only on other red algae and have over 120 described species. Developmental studies in red algal parasites are few, although they have shown that secondary pit connections formed between parasite and host and proposed that this was an important process in successful parasitism. Furthermore, it was recorded that the transfer of parasite nuclei by these secondary pit connections led to different host cell effects. We used developmental studies to reconstruct early stages and any host cell effects of a parasite on Vertebrata aterrima. A mitochondrial marker (cox1) and morphological observations (light and fluorescence microscopy) were used to describe this new red algal parasite as Vertebrata aterrimophila sp. nov. Early developmental stages show that a parasite spore connects via secondary pit connections with a pericentral host cell after cuticle penetration. Developmental observations revealed a unique connection cell that grows into a ‘trunk-like’ structure. Host cell transformation after infection by the parasite included apparent increases in both carbohydrate concentrations and nuclear size, as well as structural changes. Analyses of molecular phylogenies and reproductive structures indicated that the closest relative of V. aterrimophila is its host, V. aterrima. Our study shows a novel developmental parasite stage (‘trunk-like’ cell) and highlights the need for further developmental studies to investigate the range of developmental patterns and host effects in parasitic red algae.
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evolution of four southern hemisphere bostrychia Rhodomelaceae rhodophyta species phylogeny species delimitation and divergence times
Phycologia, 2014Co-Authors: Narongrit Muangmai, John A West, Giuseppe C ZuccarelloAbstract:Abstract: Defining species boundaries is important to address evolutionary questions and understand true biodiversity in a region. Determining the actual number of species is not trivial, and numerous species-delimitation algorithms have been developed and extensively applied to a wide range of organisms. The cosmopolitan red-algal genus Bostrychia has been used as a model system to study evolutionary processes, yet phylogeny within the genus and its true species composition are still unresolved. The four species B. arbuscula, B. gracilis, B. intricata and B. vaga represented a distinctive morphotype that was once the basis for segregation into the separate genus Stictosiphonia, and all appeared to be restricted to the Southern Hemisphere. We sequenced genes from all three genomes [plastid: rbcL; mitochondrial: cytochrome c oxidase subunit I(COI); and nuclear: large-subunit ribosomal RNA] to examine the phylogenetic relationships of the four species and to establish their diacritical features. Our phyloge...
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monosiphonous growth and cell death in an unusual bostrychia Rhodomelaceae rhodophyta b anomala sp nov
Algae, 2013Co-Authors: John A West, Susan Loiseauxde Goer, Giuseppe C ZuccarelloAbstract:A morphologically distinct lineage within the Bostrychia moritziana-B. radicans species complex is described as a new species. Bostrychia anomala has thalli with branched monosiphonous filaments with apical cell divisions. The species has terminal tetrasporangial stichidia, each subtending cell bearing tetrasporangia with 2 cover cells. Discharged spores divide transversely, the lower cell first forming a narrow rhizoid and the upper cell forming a monosiphonous shoot. Females have subterminal procarps and males have terminal spermatangial stichidia. Carposporophytes are spherical. Isolates in culture show a pattern of cell death not associated with injury, reminiscent of programmed cell death. Bostrychia anomola shows cell death at intervals along the filaments resulting in division of adjacent cells on either side of the dead cell re-joining the filament; cell division of only one adjacent cell resulting in branching at that site; or filaments fragmenting at the cell death point with adjacent cells forming new apical cells, a means of thallus propagation. The cell death pattern could be a method of filament propagation in the mangrove environment where sexual reproduction is rare.
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gall structure and specificity in bostrychia culture isolates Rhodomelaceae rhodophyta
Algae, 2013Co-Authors: John A West, Curt M Pueschel, Tatyana A Klochkova, Gwang Hoon Kim, Susan Loiseaux De Goer, Giuseppe C ZuccarelloAbstract:The descriptions of galls, or tumors, in red algae have been sparse. Ktzing (1865) observed possible galls of Bostrychia but only presented a drawing. Intensive culture observations of hundreds of specimens of the genus Bostrychia over many years have revealed that galls appeared in only a small subset of our unialgal cultures of B. kelanensis, Bostrychia moritziana/radicans, B. radicosa, B. simpliciuscula, and B. tenella and continued to be produced intermittently or continuously over many years in some cultures but were never seen in field specimens. Galls appeared as unorganized tissue found primarily on males and bisexuals, but occasionally on females and tetrasporophytes. The gall cells usually were less pigmented than neighboring tissue, but contained cells with fluorescent plastids and nuclei. The galls were not transferable to other potential hosts. Galls could be produced from gall-free tissue of cultures that originally had galls even after transfer to new culture dishes. Electon microscopy of galls on one isolate (3895) showed that virus-like particles are observed in some gall cells. It is possible that a virus is the causative agent of these galls.
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bostrychia Rhodomelaceae rhodophyta species of new zealand and relationships in the southern hemisphere
New Zealand Journal of Marine and Freshwater Research, 2008Co-Authors: Giuseppe C Zuccarello, John A WestAbstract:Abstract Bostrychia is a widespread genus and has recently received considerable molecular attention, leading to insights into its evolution, and nomenclatural changes. We investigated the species of Bostrychia in New Zealand, to produce an identification key and highlight the nomenclatural changes of these species. We incorporated into a molecular phylogeny two species prominent in New Zealand (B. gracilis, B. vaga) that have not be investigated phylogenetically before. Our results show thatthree species of Bostrychia (B. arbuscula, B. gracilis, B. vaga), mainly restricted to New Zealand, share a common ancestor. Only B. vaga is known outside New Zealand. This restricted distribution is unusual for species within this genus in which many are widespread. A phylogeographic study of another New Zealand and Southern Hemisphere species, B. intricata, indicates that this species consists of several lineages that are found locally. These lineages, and physiological difference between lineages, suggest that cryp...
Pilar Diaztapia - One of the best experts on this subject based on the ideXlab platform.
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reassessment of the genus lophurella Rhodomelaceae rhodophyta from australia and new zealand reveals four cryptic species
European Journal of Phycology, 2020Co-Authors: Pilar Diaztapia, Christine A. Maggs, Wendy A Nelson, Erasmo C Macaya, Heroen VerbruggenAbstract:Cryptic diversity is common in the red algae and is often discovered when comparing specimens from distant locations or different morphotypes of species with high phenotypic plasticity. The genus L...
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the phylogenetic position of the morphologically unusual pleurostichidium falkenbergii Rhodomelaceae rhodophyta based on plastid phylogenomics
Phycologia, 2019Co-Authors: Marisa M Pasella, Heroen Verbruggen, Wendy A Nelson, Pilar DiaztapiaAbstract:Pleurostichidium falkenbergii is an obligate epiphyte on Xiphophora chondrophylla and is endemic to northern New Zealand. This monotypic genus is characterised by having dorsiventral and laterally ...
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analysis of chloroplast genomes and a supermatrix inform reclassification of the Rhodomelaceae rhodophyta
Journal of Phycology, 2017Co-Authors: Pilar Diaztapia, Christine A. Maggs, John A West, Heroen VerbruggenAbstract: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.
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three new cryptogenic species in the tribes polysiphonieae and streblocladieae Rhodomelaceae rhodophyta
Phycologia, 2017Co-Authors: Heroen Verbruggen, Pilar Diaztapia, Ignacio Barbara, Javier Cremades, Christine A. MaggsAbstract:Abstract: During our sampling surveys of the tribes Polysiphonieae and Streblocladieae in Spain and Australia, three previously unrecorded species were collected. Based on molecular and morphological evidence they are proposed as new species. Polysiphonia delicata sp. nov. and Polysiphonia radiata sp. nov. belong to the Polysiphonieae and share the synapomorphy in this group, rhizoids in open connection to pericentral cells. They differ from other members of this group either by rbcL sequence divergences greater than 4.5% and/or by morphological characters. The third species is placed in Melanothamnus (tribe Streblocladieae), as Melanothamnus pseudoforcipatus sp. nov. In agreement with the morphological delineation of the genus, it has plastids lying only on the radial walls of pericentral cells. It can be separated from most other members of the genus by having naked segments between trichoblasts or branches and/or rbcL sequence divergences higher than 4%. In Galicia, Spain, both Polysiphonia species wer...
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seaweeds from sand covered rocks of the atlantic iberian peninsula part 1 the Rhodomelaceae ceramiales rhodophyta
Cryptogamie Algologie, 2013Co-Authors: Pilar Diaztapia, Ignacio BarbaraAbstract:Abstract Sand-covered rocks provide a particular habitat to benthic seaweeds, which must tolerate the stressful conditions imposed by the presence of sediments. Turf assemblages are dominant in this habitat, which is widely distributed along the Atlantic Iberian Peninsula, neverthelss their flora remained poorly known. This work presents a taxonomic, floristic and chorological account of the most representative Rhodomelaceae from sand-covered rocks along the Atlantic Iberian Peninsula. For each species we provided morphological descriptions, distribution maps, and/or COI-5P sequences, as well as taxonomic notes. The species studied are: Chondria coerulescens, Ctenosiphonia hypnoides, Herposiphonia cf. secunda f. tenella, Leptosiphonia schousboei, Lophosiphonia reptabunda, L. simplicissima sp. nov., Ophidocladus simpliciusculus, Polysiphonia caespitosa, P. devoniensis, P. foetidissima, P. fucoides, P. nigra, P. stricta, P. tripinnata, Pterosiphonia ardreana, P. parasitica, P. pennata and Streblocladia coll...
Heroen Verbruggen - One of the best experts on this subject based on the ideXlab platform.
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reassessment of the genus lophurella Rhodomelaceae rhodophyta from australia and new zealand reveals four cryptic species
European Journal of Phycology, 2020Co-Authors: Pilar Diaztapia, Christine A. Maggs, Wendy A Nelson, Erasmo C Macaya, Heroen VerbruggenAbstract:Cryptic diversity is common in the red algae and is often discovered when comparing specimens from distant locations or different morphotypes of species with high phenotypic plasticity. The genus L...
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Molecular survey of the red algal family Rhodomelaceae (Ceramiales, Rhodophyta) in Australia reveals new introduced species
Journal of Applied Phycology, 2019Co-Authors: Cristina Piñeiro-corbeira, Heroen Verbruggen, Pilar Díaz-tapiaAbstract:Red algae are frequently dominant components of the non-native biotas in coastal areas. They often remain undetected because of morphological similarity between native and introduced species and cryptic diversity. Routine use of DNA barcodes can aid in setting baseline tabulations of native species and for detecting introduced species. We performed an extensive survey of the red algal family Rhodomelaceae in southern Australia, producing a dataset containing more than 1100 rbc L sequences. The objective of this study was to screen that dataset for introduced species of the tribes Polysiphoniaeae and Streblocladieae, and to provide morphological information of presumably introduced species that were not previously recorded in Australia. Molecular data and morphological observations confirmed the presence of five presumably introduced species: Leptosiphonia brodiei , Melanothamnus japonicus , M. strictissimus , Polysiphonia morrowii and P. delicata . Polysiphonia morrowii and M. strictissimus were detected for the first time in Australia, and M. japonicus and P. delicata were found to be more widely distributed than previously known. Somewhat unexpectedly, the distribution range of L. brodiei has apparently shrunk, with our survey suggesting it remains only in Tasmania. Four of these species have been reported as introduced species in other countries, but M. strictissimus is here recorded for the first time outside its native New Zealand. Although all five species can be considered introduced or cryptogenic, only P. morrowii , M. japonicus and M. strictissimus were locally abundant, and further work will be needed to assess their ability to spread and effect negative impacts on native biotas.
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the phylogenetic position of the morphologically unusual pleurostichidium falkenbergii Rhodomelaceae rhodophyta based on plastid phylogenomics
Phycologia, 2019Co-Authors: Marisa M Pasella, Heroen Verbruggen, Wendy A Nelson, Pilar DiaztapiaAbstract:Pleurostichidium falkenbergii is an obligate epiphyte on Xiphophora chondrophylla and is endemic to northern New Zealand. This monotypic genus is characterised by having dorsiventral and laterally ...
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analysis of chloroplast genomes and a supermatrix inform reclassification of the Rhodomelaceae rhodophyta
Journal of Phycology, 2017Co-Authors: Pilar Diaztapia, Christine A. Maggs, John A West, Heroen VerbruggenAbstract: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.
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three new cryptogenic species in the tribes polysiphonieae and streblocladieae Rhodomelaceae rhodophyta
Phycologia, 2017Co-Authors: Heroen Verbruggen, Pilar Diaztapia, Ignacio Barbara, Javier Cremades, Christine A. MaggsAbstract:Abstract: During our sampling surveys of the tribes Polysiphonieae and Streblocladieae in Spain and Australia, three previously unrecorded species were collected. Based on molecular and morphological evidence they are proposed as new species. Polysiphonia delicata sp. nov. and Polysiphonia radiata sp. nov. belong to the Polysiphonieae and share the synapomorphy in this group, rhizoids in open connection to pericentral cells. They differ from other members of this group either by rbcL sequence divergences greater than 4.5% and/or by morphological characters. The third species is placed in Melanothamnus (tribe Streblocladieae), as Melanothamnus pseudoforcipatus sp. nov. In agreement with the morphological delineation of the genus, it has plastids lying only on the radial walls of pericentral cells. It can be separated from most other members of the genus by having naked segments between trichoblasts or branches and/or rbcL sequence divergences higher than 4%. In Galicia, Spain, both Polysiphonia species wer...