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Benjamin Øllgaard - One of the best experts on this subject based on the ideXlab platform.
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Lycopodiaceae in Colombia: Subfamilies Lycopodioideae and Lycopodielloideae.
Phytotaxa, 2020Co-Authors: Benjamin ØllgaardAbstract:Following the treatment of the Colombian species belonging to the genus Phlegmariurus (Lycopodiaceae, subfamily Huperzioideae) by Øllgaard (2019), the present study deals with the remaining genera of the family, belonging to the subfamilies Lycopodioideae (Austrolycopodium, Diphasiastrum, Diphasium, and Lycopodium s.str.,) and Lycopodielloideae (Lycopodiella s.str., Palhinhaea, and Pseudolycopodiella).
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The Lycopodiaceae of Guyana, Suriname, and French Guiana
Phytotaxa, 2020Co-Authors: Benjamin Øllgaard, Michel Boudrie, Georges CremersAbstract:The present paper provides keys to the genera and species of Lycopodiaceae for the 5 genera and 25 species recorded from Guyana, Suriname, and French Guiana. The treatment includes nomenclature, descriptions of species, and information about distribution and habitats, and notes on problems of species delimitation and infraspecific variation. All species are illustrated, and representative specimens are cited.
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Synopsis of the genus Phlegmariurus (Lycopodiaceae) in Colombia
Phytotaxa, 2019Co-Authors: Benjamin ØllgaardAbstract:This article presents the results of a study of a large material of Colombian Lycopodiaceae, describing 75 species of the genus Phlegmariurus, some of them subdivided into several varieties. Their nomenclature, distribution and habitats are indicated, and problems of species delimitation and infraspecific variation are discussed. All species are illustrated, and studied specimens are cited. An attempt has been made to group the species, mainly following the clades of recent molecular studies. The following taxa are described as new to science: Phlegmariurus cocuyensis, P. cruentus var. exilis, P. cruentus var. illimitatus, P. idroboi, and P. josesantae.
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Prodromus of a fern flora for Bolivia. II. Lycopodiaceae
Phytotaxa, 2018Co-Authors: Benjamin Øllgaard, Michael Kessler, Alan R. SmithAbstract:We provide a synopsis to the family Lycopodiaceae in Bolivia, including 40 species (some with varieties) in eight genera. One new species, Phlegmariurus stephani B.Ollg., is described. Keys are given to genera and species. Most relevant synonyms are mentioned, the general and Bolivian distribution and ecology is summarized, and some notes on related species are given.
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New neotropical Lycopodiaceae
Phytotaxa, 2016Co-Authors: Benjamin ØllgaardAbstract:The following species in the Lycopodiaceae are described as new to science: Palhinhaea cerrojefensis (Panama), Phlegmariurus pachyskelos (Colombia), Phlegmariurus silverstonei (Colombia), Phlegmariurus sphagnicola (Colombia), and Phlegmariurus tryonorum (Costa Rica). Phlegmariurus serpentiformis (Herter) B.Ollg. is a new combination.
Jaideep Mazumdar - One of the best experts on this subject based on the ideXlab platform.
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Correction to Phytotaxa 226: Neotypification of Urostachys vorwerkii (Lycopodiaceae)
Phytotaxa, 2016Co-Authors: Jaideep MazumdarAbstract:In a previous correspondence (Mazumdar 2015) I reported that Urostachys vorwerkii Nessel (1934: 178), Lycopodiaceae, was the earliest legitimate name for plants currently known as Huperzia arunachalensis (D.D.Pant & P.S.Pandey) Fraser-Jenkins in Fraser-Jenkins et al. (2015: 45). Due to unavailability of original specimens of Urostachys vorwerkii I selected a neotype. However, I mistakenly overlooked the photograph associated with the protologue (Nessel 1934, t. 170), which should be treated as original material. I hereby select this photograph as the lectotype and the specimen previously selected as neotype is changed into an epitype.
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Neotypification of Urostachys vorwerkii (Lycopodiaceae)
Phytotaxa, 2015Co-Authors: Jaideep MazumdarAbstract:Nessel (1934) first described the name Urostachys vorwerkii Nessel (1934: 178) (Lycopodiaceae) based on Himalayan specimen from unknown locality in India. But this name is largely overlooked in Indian literature.
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Typifications of some Lycopodiaceae from India
Webbia, 2015Co-Authors: Jaideep MazumdarAbstract:As a part of revision of Lycopodiaceae in India lectotypes for Huperzia ceylanica, Diphasiastrum wightianum, Phlegmariurus carinatus, Phlegmariurus pulcherrimus, Phlegmariurus ulicifolius and Phlegmariurus vernicosus and a neotype for Phlegmariurus aloifolius are selected.
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HUPERZIA ARUNACHALENSIS (Lycopodiaceae) A NEW LYCOPOD FROM INDIA
2014Co-Authors: Jaideep Mazumdar, R. MukhopadhyayAbstract:A new lycophyte species Huperzia arunachalensis (Lycopodiaceae) is described from Arunachal Pradesh, India.
Niklas Wikström - One of the best experts on this subject based on the ideXlab platform.
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Revised lectotypification of Lycopodium complanatum L. (Lycopodiaceae)
TAXON, 2009Co-Authors: Mats Thulin, Niklas Wikström, Sunniva Margrethe Due Aagaard, Charles E. JarvisAbstract:In this thesis relationships and the occurrence of reticulate evolutionary events in the club moss genus Diphasiastrum are investigated. Diphasiastrum is initially established as a monophyletic group within Lycopodiaceae using non recombinant chloroplast sequence data. Support is obtained for eight distinct parental lineages in Diphasiastrum, and relationships among the putative parent taxa in the hypothesized hybrid complexes; D. alpinum, D. complanatum, D. digitatum, D. multispicatum, D. sitchense, D. tristachyum and D. veitchii are presented. Feulgen DNA image densitometry data and sequence data obtained from three nuclear regions, RPB2, LEAFY and LAMB4, were used to infer the origins of three different taxa confirmed to be allopolyploid; D. zanclophyllum from South Africa, D. wightianum from Malaysia and an undescribed taxon from China. The two Asian polyploids have originated from two different hybrid combinations, D. multispicatum x D. veitchii and D. tristachyum x D. veitchii. Diphasiastrum zanclophyllum originates from a cross between D. digitatum and an unidentified diploid taxon. The occurrence of three homoploid hybrid combinations commonly recognized in Europe, D. alpinum x D. complanatum, D. alpinum x D. tristachyum and D. complanatum x D. tristachyum, are verified using the same three nuclear regions. Two of the three hybrid combinations are also shown to have originated from reciprocal crosses. Admixture analyses performed on an extended, dataset similarly identified predominately F1 hybrids and backcrosses. The observations and common recognition of hybrid species in the included populations are hence most likely due to frequent observations of neohybrids in hybrid zones. Reticulate patterns are, however, prominent in the presented dataset. Hence future studies addressing evolutionary and ecological questions in Diphasiastrum should emphasize the impact of gene flow between parent lineages rather than speciation as the result of hybridization.
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homoploid hybridization in central european diphasiastrum Lycopodiaceae
2009Co-Authors: Sunniva M D Aagaard, Niclas Gyllenstrand, Niklas WikströmAbstract:Three species of homoploid hybrid origin are commonly recognized among Central European Diphasiastrum, and reticulate evolutionary events have for a long time been acknowledged as an important fact ...
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Evolution of Lycopodiaceae (Lycopsida): estimating divergence times from rbcL gene sequences by use of nonparametric rate smoothing.
Molecular Phylogenetics and Evolution, 2001Co-Authors: Niklas Wikström, Paul KenrickAbstract:Abstract By use of nonparametric rate smoothing and nucleotide sequences of the rbcL gene, divergence times in Lycopodiaceae are estimated. The results show that much extant species diversity in Lycopodiaceae stems from relatively recent cladogenic events. These results corroborate previous ideas based on paleobotanical and biogeographical data. Previous molecular phylogenetic analyses recognized a split into neotropical and paleotropical clades in Huperzia, which contains 85–90% of all living species. Connecting this biogeographical pattern with continent movements, the diversification of this epiphytic group was suggested to coincide with that of angiosperms in the mid to Late Cretaceous. Results presented here are consistent with this idea, and the diversification of the two clades is resolved as Late Cretacous (78 and 95 Myr). In the related genera Lycopodium and Lycopodiella, the patterns are somewhat different. Here species diversity is scattered among different subgeneric groups. Most of the high-diversity subgeneric groups seem to have diversified very recently (Late Tertiary), whereas the cladogenic events leading to these groups are much older (Early to Late Cretaceous). Our analysis shows that, although much living species diversity stems from relatively recent cladogenesis, the origins of the family (Early Carboniferous) and generic crown groups (Early Permian to Early Jurassic) are much more ancient events.
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Phylogeny of epiphytic Huperzia (Lycopodiaceae): paleotropical and neotropical clades corroborated by rbcL sequences
Nordic Journal of Botany, 2000Co-Authors: Niklas Wikström, Paul KenrickAbstract:The phylogenetic relationships of Lycopodiaceae, and specifically the relationships among epiphytic Huperzia, were investigated by means of a cladistic analysis using plastid rbcL gene sequences. Huperzia species are partitioned into neotropical and paleotropical clades, a result that is incongruent with traditional morphology based taxonomy. The rbcL data corroborate an earlier study based on tmL intron and tmL-trnF spacer sequences. Together, these two molecular studies provide strong evidence that the diversification of epiphytic Huperzia is a comparatively recent phenomenon (Late Cretaceous-Tertiary), and that there has been widespread morphological convergence in epiphytes throughout the tropics.
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Epiphytism and terrestrialization in tropicalHuperzia (Lycopodiaceae)
Plant Systematics and Evolution, 1999Co-Authors: Niklas Wikström, Paul Kenrick, M. ChaseAbstract:A phylogenetic analysis of Huperzia (Lycopodiaceae) documents a single origin of epiphytism and multiple reversals to a terrestrial habit in the Neotropics. Epiphytism evolved prior to the final rifting of South America and Africa, but the origin of most modern species diversity probably postdates the Mid Cretaceous diversification of flowering plants. In this respect, the evolution of Huperzia parallels that of many other Neotropical epiphytic groups. In the Andes, alpine terrestrial species are shown to have evolved from montane epiphytes, an event that correlates well with regional orogenesis during the Miocene. Species from Australia, New Zealand, and Tasmania show diverse relationships with SE Asian groups. Results also indicate that long distance, transoceanic dispersal is rare in these homosporous plants — accounting for less than 5% of species distributions — and that convergence in strobilus and branch morphology is widespread among Paleotropical and Neotropical epiphytes. The phylogenetic analysis is based on a sample of 63 species (c. 15% total species diversity) and data from a c. 1.1kb region of noncoding (intron and spacer sequences) plastid DNA located between the trn L and trn F genes.
Paul Kenrick - One of the best experts on this subject based on the ideXlab platform.
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Evolution of Lycopodiaceae (Lycopsida): estimating divergence times from rbcL gene sequences by use of nonparametric rate smoothing.
Molecular Phylogenetics and Evolution, 2001Co-Authors: Niklas Wikström, Paul KenrickAbstract:Abstract By use of nonparametric rate smoothing and nucleotide sequences of the rbcL gene, divergence times in Lycopodiaceae are estimated. The results show that much extant species diversity in Lycopodiaceae stems from relatively recent cladogenic events. These results corroborate previous ideas based on paleobotanical and biogeographical data. Previous molecular phylogenetic analyses recognized a split into neotropical and paleotropical clades in Huperzia, which contains 85–90% of all living species. Connecting this biogeographical pattern with continent movements, the diversification of this epiphytic group was suggested to coincide with that of angiosperms in the mid to Late Cretaceous. Results presented here are consistent with this idea, and the diversification of the two clades is resolved as Late Cretacous (78 and 95 Myr). In the related genera Lycopodium and Lycopodiella, the patterns are somewhat different. Here species diversity is scattered among different subgeneric groups. Most of the high-diversity subgeneric groups seem to have diversified very recently (Late Tertiary), whereas the cladogenic events leading to these groups are much older (Early to Late Cretaceous). Our analysis shows that, although much living species diversity stems from relatively recent cladogenesis, the origins of the family (Early Carboniferous) and generic crown groups (Early Permian to Early Jurassic) are much more ancient events.
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Phylogeny of epiphytic Huperzia (Lycopodiaceae): paleotropical and neotropical clades corroborated by rbcL sequences
Nordic Journal of Botany, 2000Co-Authors: Niklas Wikström, Paul KenrickAbstract:The phylogenetic relationships of Lycopodiaceae, and specifically the relationships among epiphytic Huperzia, were investigated by means of a cladistic analysis using plastid rbcL gene sequences. Huperzia species are partitioned into neotropical and paleotropical clades, a result that is incongruent with traditional morphology based taxonomy. The rbcL data corroborate an earlier study based on tmL intron and tmL-trnF spacer sequences. Together, these two molecular studies provide strong evidence that the diversification of epiphytic Huperzia is a comparatively recent phenomenon (Late Cretaceous-Tertiary), and that there has been widespread morphological convergence in epiphytes throughout the tropics.
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Epiphytism and terrestrialization in tropicalHuperzia (Lycopodiaceae)
Plant Systematics and Evolution, 1999Co-Authors: Niklas Wikström, Paul Kenrick, M. ChaseAbstract:A phylogenetic analysis of Huperzia (Lycopodiaceae) documents a single origin of epiphytism and multiple reversals to a terrestrial habit in the Neotropics. Epiphytism evolved prior to the final rifting of South America and Africa, but the origin of most modern species diversity probably postdates the Mid Cretaceous diversification of flowering plants. In this respect, the evolution of Huperzia parallels that of many other Neotropical epiphytic groups. In the Andes, alpine terrestrial species are shown to have evolved from montane epiphytes, an event that correlates well with regional orogenesis during the Miocene. Species from Australia, New Zealand, and Tasmania show diverse relationships with SE Asian groups. Results also indicate that long distance, transoceanic dispersal is rare in these homosporous plants — accounting for less than 5% of species distributions — and that convergence in strobilus and branch morphology is widespread among Paleotropical and Neotropical epiphytes. The phylogenetic analysis is based on a sample of 63 species (c. 15% total species diversity) and data from a c. 1.1kb region of noncoding (intron and spacer sequences) plastid DNA located between the trn L and trn F genes.
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Phylogeny of Lycopodiaceae (Lycopsida) and the Relationships of Phylloglossum drummondii Kunze Based on rbcL Sequences
International Journal of Plant Sciences, 1997Co-Authors: Niklas Wikström, Paul KenrickAbstract:A cladistic analysis based on rbcL sequences from a representative sample of 12 species yields a single most parsimonious tree that supports monophyly of Lycopodiaceae, Lycopodium, and Lycopodiella. Huperzia is resolved as paraphyletic to the morphologically divergent, monotypic Australasian Phylloglossum. The Huperzia-Phylloglossum clade is strongly supported and is sister group to a Lycopodium-Lycopodiella clade. These results provide the first clear evidence for the relationships of the problematic Phylloglossum drummondii. Profound differences in life cycle and morphology between Phylloglossum and other Lycopodiaceae are interpreted in terms of pedomorphosis (specifically, progenesis) and are viewed as adaptive responses to drought and brush fire. Our results show that rbcL sequence divergence among neotropical species of the supposedly ancient genus Huperzia is extremely low and that additional data will be necessary to resolve relationships among epiphytes and ground-living species. These surprising...
David S. Barrington - One of the best experts on this subject based on the ideXlab platform.
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overcoming among lineage rate heterogeneity to infer the divergence times and biogeography of the clubmoss family Lycopodiaceae
Journal of Biogeography, 2018Co-Authors: Weston L. Testo, Ashley R. Field, David S. BarringtonAbstract:Aim: To infer divergence times and historical biogeography of the cosmopolitan lycophyte family Lycopodiaceae. Location: Worldwide. Methods: We generated time‐calibrated phylogenies of the Lycopodiaceae based on six regions of chloroplast DNA using a node‐dating approach implemented in beast with eight fossil calibrations. To investigate effects of among‐lineage substitution rate heterogeneity on divergence time estimation, we compared the performance of two relaxed clock models: an uncorrelated lognormal clock model and a random local clock (RLC) model. The historical biogeography of the family was inferred using two Bayesian models implemented in BioGeoBEARS. Results: Divergence time estimates for major groups of the Lycopodiaceae obtained using the two substitution clock models differed substantially, and the RLC model was a better fit. The Lycopodiaceae crown group age is estimated to be late Devonian, and most deep divergence events date to the Carboniferous, with most extant species diversity accumulating during the Cenozoic. The timing of divergences of major clades in the Lycopodiaceae corresponds to the breakup of the Pangaean and Gondwanan supercontinents. Long‐distance dispersal events are relatively common, but generally do not appear to be followed by subsequent radiations. Main conclusions: Accounting for among‐lineage substitution rate heterogeneity improves divergence time estimates for the Lycopodiaceae. The family has a deep evolutionary history, and continent‐scale vicariance events in the Mesozoic appear to have been associated with major cladogenesis events, with long‐distance dispersal playing a relatively minor role.
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Overcoming among‐lineage rate heterogeneity to infer the divergence times and biogeography of the clubmoss family Lycopodiaceae
Journal of Biogeography, 2018Co-Authors: Weston L. Testo, Ashley R. Field, David S. BarringtonAbstract:Aim: To infer divergence times and historical biogeography of the cosmopolitan lycophyte family Lycopodiaceae. Location: Worldwide. Methods: We generated time‐calibrated phylogenies of the Lycopodiaceae based on six regions of chloroplast DNA using a node‐dating approach implemented in beast with eight fossil calibrations. To investigate effects of among‐lineage substitution rate heterogeneity on divergence time estimation, we compared the performance of two relaxed clock models: an uncorrelated lognormal clock model and a random local clock (RLC) model. The historical biogeography of the family was inferred using two Bayesian models implemented in BioGeoBEARS. Results: Divergence time estimates for major groups of the Lycopodiaceae obtained using the two substitution clock models differed substantially, and the RLC model was a better fit. The Lycopodiaceae crown group age is estimated to be late Devonian, and most deep divergence events date to the Carboniferous, with most extant species diversity accumulating during the Cenozoic. The timing of divergences of major clades in the Lycopodiaceae corresponds to the breakup of the Pangaean and Gondwanan supercontinents. Long‐distance dispersal events are relatively common, but generally do not appear to be followed by subsequent radiations. Main conclusions: Accounting for among‐lineage substitution rate heterogeneity improves divergence time estimates for the Lycopodiaceae. The family has a deep evolutionary history, and continent‐scale vicariance events in the Mesozoic appear to have been associated with major cladogenesis events, with long‐distance dispersal playing a relatively minor role.
