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Carles Martinclosas - One of the best experts on this subject based on the ideXlab platform.
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european charophyte evolution across the cretaceous paleogene boundary
Palaeogeography Palaeoclimatology Palaeoecology, 2019Co-Authors: Alba Vicente, Zoltan Csikisava, Carles MartinclosasAbstract:Abstract The Cretaceous–Paleogene (K/Pg) boundary has traditionally been considered a key moment in charophyte evolution, marked by the extinction of two important Mesozoic families, the Porocharaceae and the Clavatoraceae, and a major turnover within the Characeae. However, new data presented here suggest that one species of the European Porocharaceae (based on gyrogonites) and one species of the Clavatoraceae (based on thalli), persisted into the basal Danian. In addition, a taxonomic revision of the Characeae, coupled with an updated biostratigraphy, shows that this family underwent a step-wise extinction during the latest Cretaceous with only a small number of species becoming extinct at the K/Pg boundary. As a result, changes in charophyte floras around the K/Pg boundary in Europe cannot be considered to represent a major turnover in charophyte evolution. Its effects were more comparable to a normal stage boundary event rather than to a major erathem boundary one. Similar disappearance patterns at the K/Pg boundary have also been recorded in other taxa, including fish and amphibians, showing that aquatic freshwater biotas may somehow be resilient to catastrophic events such as those that occurred during the K/Pg crisis.
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towards an integrated understanding of charophyte biology and paleobiology
Botany Letters, 2018Co-Authors: Mary J Beilby, Andrzej Puckacz, Susanne C. Schneider, Carles MartinclosasAbstract:AbstractIn this special issue, we present an overview of the presentations given at the 7th Meeting of the International Research Group on charophytes held in Astana in 2016. Charophytes, understood as the members of extant Charales and their direct ancestors (fossil orders Sycidiales and Moellerinales), represent a significant plant group that provides an iconic research system for many diverse fields, such as evolution, ecology, electrophysiology, phytoremediation and management of wetlands. Charophytes have been proposed as one of the closest ancestors of land plants. Their fossil record goes back to 425 Ma (million years ago), but the rise of the oldest living charophyte genera is dated from ca 155–125 Ma. An example of vegetations already dominated by early Characeae has been recently found in China, dating back to that time. The definition of charophyte species has been a matter of debate, since the morphology of these plants shows a great plasticity. The elucidation of charophyte taxonomy is of maj...
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effects of light and temperature on chara vulgaris charophyceae gyrogonite productivity and polymorphism palaeoenvironmental implications
Phycologia, 2017Co-Authors: Alba Vicente, Josep Sanjuan, Nuria Florarnau, Toni Monleon, Jaume Cambra, Carles MartinclosasAbstract:Abstract: To test the influence of light and temperature on intraspecific gyrogonite variation, two common European charophyte species, Chara vulgaris and Chara globularis, were studied indoors under controlled environmental conditions. A total of 60 plants of each species were incubated under different combinations of four irradiances (L1 = 30 μmol PAR m−2 s−1; L2 = 150 μmol PAR m−2 s−1; L3 = 500 μmol PAR m−2 s−1 and L4 = 1000 μmol PAR m−2 s−1) and three water temperatures (T1 = 15°C; T2 = 25°C and T3 = 35°C). These parameters simulate temporary ponds from the Mediterranean region in the summer and help in understanding charophyte reproduction in shallow temporary ponds of past geological periods. After 102 days, gyrogonite productivity was evaluated, and a morphometric analysis of the gyrogonites produced was performed. Our results indicated that both irradiance and water temperature play a key role in C. vulgaris intraspecific gyrogonite variation. Gyrogonites tended to increase their size as irradianc...
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revision of the maastrichtian palaeocene charophyte biostratigraphy of the fontllonga reference section southern pyrenees catalonia spain
Geologica Acta, 2016Co-Authors: Alba Vicente, S Villalbabreva, Carles Ferrandezcanadell, Carles MartinclosasAbstract:The Fontllonga section is one of the best-known stratigraphic sections wordwide for the study of charophyte biostratigraphy of the Maastrichtian and lower Palaeocene. An updated proposal for the charophyte biostratigraphy of this section is presented after summarizing previous knowledge. The zone of Peckichara cancellata allows the upper Campanian–lowermost Maastrichtian to be characterised in the base of the section (La Macana Formation). The Microchara punctata biozone represents most of the Maastrichtian (Figuerola Formation). Within this biozone, a Clavator ultimus subzone is proposed to improve characterisation of the lower and middle Maastrichtian. Both the upper and lower boundaries of the Microchara punctata biozone proposed in previous studies are modified based on new occurrences of the index species. A charophyte assemblage belonging to the Dughiella bacillaris biozone is reported for the first time from the middle of the section (Perauba Complex) and provides an age for this unit ranging from the upper Danian to lower Thanetian. A foraminifer assemblage found in the basal marine deposits above the non-marine succession of the Fontllonga section provides new biostratigraphic data to locate the upper boundary of the non-marine succession at least within the upper Thanetian.
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maastrichtian basal paleocene charophyte biozonation and its calibration to the global polarity time scale in the southern pyrenees catalonia spain
Cretaceous Research, 2015Co-Authors: Alba Vicente, Carles MartinclosasAbstract:Abstract A new charophyte biozonation for the non-marine Maastrichtian−lowermost Paleocene deposits in the South-Eastern Pyrenean Vallcebre Basin is proposed and calibrated to the Global Polarity Time Scale (GPTS) using magnetostratigraphic data. Planktonic foraminifera associated with charophyte assemblages provide maximum ages for correlation between non-marine and marine biostratigraphic zonations. The new charophyte biozonation is intended to be useful for terrigenous floodplain facies (red beds) with poorly developed lacustrine intervals and strong palaeoecological constraints for the development of charophytes. The taxonomy of charophytes was revisited and two new species were defined, Microchara nana Vicente and Martin-Closas and Peckichara serrata Vicente and Martin-Closas. Sedimentological analyses carried out in parallel with taphonomic observations allow us to infer the palaeoecological constraints of charophyte species. The new biozonation encompasses three biozones for the late Campanian−early Paleocene interval. The partial range biozone of Peckichara cancellata starts in chron C32r (∼73.91 Ma) according to previous studies, and extends its upper limit to chron C31r, with an age of ∼69.90 Ma in the Vallcebre Basin. The new Microchara punctata local biozone includes biozones of Septorella ultima (upper part), Microchara cristata and Peckichara sp. 1 (lower part) previously defined by Feist in Riveline et al. (1996). Some of these biozones were poorly characterized or were based on species with strong palaeoecological constraints. The lower Danian is characterized by the biozone of Peckichara toscarensis, replacing the previous biozone of Peckichara llobregatensis. The latter species was found to occur in the Maastrichtian.
Palacio, Jaime A. - One of the best experts on this subject based on the ideXlab platform.
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Charophyta, Chlorophyta y Cryptophyta del embalse Riogrande II (Antioquia), Colombia
'Instituto de Investigacion de Recursos Biologicos Alexander von Humboldt (IAVH)', 2019Co-Authors: López Muñoz, Mónica Tatiana, De Mattos Bicudo, Carlos Eduardo, Ramírez-restrepo, John Jairo, Palacio, Jaime A.Abstract:En muestras recolectadas mensualmente, entre agosto de 2011 y agosto de 2012, en el embalse Riogrande II(cuenca del río Grande, Antioquia, Colombia), se identificaron en total 29 géneros, 48 especies y una variedadtaxonómica, pertenecientes a Charophyta, Chlorophyta y Cryptophyta. De las 48 especies, 18 especies y unavariedad, son nuevos reportes para la ficoflórula colombiana. La división con mayor número de géneros fueChlorophyta, sin embargo, Staurastrum (Charophyta) fue el género más diverso y de mayor contribución a labiomasa. Las diferencias entre las características descritas en la literatura y las observadas en los ejemplares,dificultaron la determinación taxonómica, lo cual plantea la necesidad de realizar estudios morfológicosdetallados.Artículo revisado por pare
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Charophyta, Chlorophyta y Cryptophyta del embalse Riogrande II (Cuenca del río Grande, Antioquia, Colombia)
2017Co-Authors: López Muñoz, Mónica Tatiana, De Mattos Bicudo, Carlos Eduardo, Ramírez-restrepo, John Jairo, Echenique, Ricardo O., Palacio, Jaime A.Abstract:En muestras recolectadas mensualmente, entre agosto de 2011 y agosto de 2012, en el embalse Riogrande II (cuenca del río Grande, Antioquia, Colombia), se identificaron en total 29 géneros, 48 especies y una variedad taxonómica, pertenecientes a Charophyta, Chlorophyta y Cryptophyta. De las 48 especies, 18 especies y una variedad, son nuevos reportes para la ficoflórula colombiana. La división con mayor número de géneros fue Chlorophyta, sin embargo, Staurastrum (Charophyta) fue el género más diverso y de mayor contribución a la biomasa. Las diferencias entre las características descritas en la literatura y las observadas en los ejemplares, dificultaron la determinación taxonómica, lo cual plantea la necesidad de realizar estudios morfológicos detallados.Bogotá, Colombi
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Charophyta, Chlorophyta y Cryptophyta del embalse Riogrande II (Antioquia), Colombia
'Instituto de Investigacion de Recursos Biologicos Alexander von Humboldt (IAVH)', 2017Co-Authors: López Muñoz, Mónica Tatiana, De Mattos Bicudo, Carlos Eduardo, Ramírez-restrepo, John Jairo, Echenique, Ricardo O., Palacio, Jaime A.Abstract:In monthly samples collected from August 2011 to August 2012 in the Riogrande II reservoir (Grande River drainage, Antioquia, Colombia). 29 genera, 48 species and one taxonomic variety belonging to Charophyta, Chlorophyta and Cryptophyta were identified. 18 species and one variety are new reports to the algal flora of Colombia. Chlorophyta was the Division with the largest number of genera and Staurastrum (Charophyta) the most diverse genus and also the largest contributer to biomass. Differences from the characteristics described in the literature and those observed in the specimens studied, made some taxonomic identification rather difficult, pointing out the need for careful and meticulous morphological studies before reaching taxonomical identifications.En muestras recolectadas mensualmente, entre agosto de 2011 y agosto de 2012, en el embalse Riogrande II(cuenca del río Grande, Antioquia, Colombia), se identificaron en total 29 géneros, 48 especies y una variedadtaxonómica, pertenecientes a Charophyta, Chlorophyta y Cryptophyta. De las 48 especies, 18 especies y unavariedad, son nuevos reportes para la ficoflórula colombiana. La división con mayor número de géneros fueChlorophyta, sin embargo, Staurastrum (Charophyta) fue el género más diverso y de mayor contribución a labiomasa. Las diferencias entre las características descritas en la literatura y las observadas en los ejemplares,dificultaron la determinación taxonómica, lo cual plantea la necesidad de realizar estudios morfológicosdetallados
Alba Vicente - One of the best experts on this subject based on the ideXlab platform.
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european charophyte evolution across the cretaceous paleogene boundary
Palaeogeography Palaeoclimatology Palaeoecology, 2019Co-Authors: Alba Vicente, Zoltan Csikisava, Carles MartinclosasAbstract:Abstract The Cretaceous–Paleogene (K/Pg) boundary has traditionally been considered a key moment in charophyte evolution, marked by the extinction of two important Mesozoic families, the Porocharaceae and the Clavatoraceae, and a major turnover within the Characeae. However, new data presented here suggest that one species of the European Porocharaceae (based on gyrogonites) and one species of the Clavatoraceae (based on thalli), persisted into the basal Danian. In addition, a taxonomic revision of the Characeae, coupled with an updated biostratigraphy, shows that this family underwent a step-wise extinction during the latest Cretaceous with only a small number of species becoming extinct at the K/Pg boundary. As a result, changes in charophyte floras around the K/Pg boundary in Europe cannot be considered to represent a major turnover in charophyte evolution. Its effects were more comparable to a normal stage boundary event rather than to a major erathem boundary one. Similar disappearance patterns at the K/Pg boundary have also been recorded in other taxa, including fish and amphibians, showing that aquatic freshwater biotas may somehow be resilient to catastrophic events such as those that occurred during the K/Pg crisis.
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effects of light and temperature on chara vulgaris charophyceae gyrogonite productivity and polymorphism palaeoenvironmental implications
Phycologia, 2017Co-Authors: Alba Vicente, Josep Sanjuan, Nuria Florarnau, Toni Monleon, Jaume Cambra, Carles MartinclosasAbstract:Abstract: To test the influence of light and temperature on intraspecific gyrogonite variation, two common European charophyte species, Chara vulgaris and Chara globularis, were studied indoors under controlled environmental conditions. A total of 60 plants of each species were incubated under different combinations of four irradiances (L1 = 30 μmol PAR m−2 s−1; L2 = 150 μmol PAR m−2 s−1; L3 = 500 μmol PAR m−2 s−1 and L4 = 1000 μmol PAR m−2 s−1) and three water temperatures (T1 = 15°C; T2 = 25°C and T3 = 35°C). These parameters simulate temporary ponds from the Mediterranean region in the summer and help in understanding charophyte reproduction in shallow temporary ponds of past geological periods. After 102 days, gyrogonite productivity was evaluated, and a morphometric analysis of the gyrogonites produced was performed. Our results indicated that both irradiance and water temperature play a key role in C. vulgaris intraspecific gyrogonite variation. Gyrogonites tended to increase their size as irradianc...
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revision of the maastrichtian palaeocene charophyte biostratigraphy of the fontllonga reference section southern pyrenees catalonia spain
Geologica Acta, 2016Co-Authors: Alba Vicente, S Villalbabreva, Carles Ferrandezcanadell, Carles MartinclosasAbstract:The Fontllonga section is one of the best-known stratigraphic sections wordwide for the study of charophyte biostratigraphy of the Maastrichtian and lower Palaeocene. An updated proposal for the charophyte biostratigraphy of this section is presented after summarizing previous knowledge. The zone of Peckichara cancellata allows the upper Campanian–lowermost Maastrichtian to be characterised in the base of the section (La Macana Formation). The Microchara punctata biozone represents most of the Maastrichtian (Figuerola Formation). Within this biozone, a Clavator ultimus subzone is proposed to improve characterisation of the lower and middle Maastrichtian. Both the upper and lower boundaries of the Microchara punctata biozone proposed in previous studies are modified based on new occurrences of the index species. A charophyte assemblage belonging to the Dughiella bacillaris biozone is reported for the first time from the middle of the section (Perauba Complex) and provides an age for this unit ranging from the upper Danian to lower Thanetian. A foraminifer assemblage found in the basal marine deposits above the non-marine succession of the Fontllonga section provides new biostratigraphic data to locate the upper boundary of the non-marine succession at least within the upper Thanetian.
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maastrichtian basal paleocene charophyte biozonation and its calibration to the global polarity time scale in the southern pyrenees catalonia spain
Cretaceous Research, 2015Co-Authors: Alba Vicente, Carles MartinclosasAbstract:Abstract A new charophyte biozonation for the non-marine Maastrichtian−lowermost Paleocene deposits in the South-Eastern Pyrenean Vallcebre Basin is proposed and calibrated to the Global Polarity Time Scale (GPTS) using magnetostratigraphic data. Planktonic foraminifera associated with charophyte assemblages provide maximum ages for correlation between non-marine and marine biostratigraphic zonations. The new charophyte biozonation is intended to be useful for terrigenous floodplain facies (red beds) with poorly developed lacustrine intervals and strong palaeoecological constraints for the development of charophytes. The taxonomy of charophytes was revisited and two new species were defined, Microchara nana Vicente and Martin-Closas and Peckichara serrata Vicente and Martin-Closas. Sedimentological analyses carried out in parallel with taphonomic observations allow us to infer the palaeoecological constraints of charophyte species. The new biozonation encompasses three biozones for the late Campanian−early Paleocene interval. The partial range biozone of Peckichara cancellata starts in chron C32r (∼73.91 Ma) according to previous studies, and extends its upper limit to chron C31r, with an age of ∼69.90 Ma in the Vallcebre Basin. The new Microchara punctata local biozone includes biozones of Septorella ultima (upper part), Microchara cristata and Peckichara sp. 1 (lower part) previously defined by Feist in Riveline et al. (1996). Some of these biozones were poorly characterized or were based on species with strong palaeoecological constraints. The lower Danian is characterized by the biozone of Peckichara toscarensis, replacing the previous biozone of Peckichara llobregatensis. The latter species was found to occur in the Maastrichtian.
Adriana Garcia - One of the best experts on this subject based on the ideXlab platform.
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carbon stable isotope composition of charophyte organic matter in a small and shallow spanish water body as a baseline for future trophic studies
Journal of Limnology, 2015Co-Authors: María A. Rodrigo, Adriana Garcia, Allan R ChivasAbstract:Quantitative descriptions of foodweb structure based on isotope niche space require knowledge of producers’ isotopic signatures. In freshwater ecosystems charophytes are one of the main components of submerged vegetation and the feeding base for many herbivorous consumers, but knowledge about their organic carbon isotopic signatures is sparse. In this study, the δ 13 C organic values (and organic %C and %N) of the four species of submerged macrophytes (three charophytes - Chara hispida , Nitella hyalina and Tolypella glomerata - and one angiosperm, Myriophyllum spicatum ) growing in a newly created shallow pond were measured monthly over a period of one year, to discern if i) all charophyte species susceptible to being food for consumers and growing in the same waterbody have the same C isotopic composition; ii) the δ 13 C values of a charophyte species change on a seasonal and spatial scale; iii) the different parts (apical nodes, internodes, rhizoids, reproductive organs, oospores) of a charophyte species have the same isotopic composition. The δ 13 C, %C and %N values of organic matter in the sediments where the plants were rooted were also measured as well as several limnological variables. The δ 13 C values for the angiosperm (-13.7±0.7‰) indicated 13 C-enrichment, whereas the N. hyalina δ 13 C values were the most negative (-22.4±0.7‰). The mean δ 13 C value for C. hispida was -19.0±1.0‰ and -20.7±0.8‰ for T. glomerata. C. hispida δ 13 C values had a significant seasonal variation with 13 C-poor values in the cold season, and slight spatial differences. Statistically significant differences were found between charophyte rhizoids ( 13 C-enriched) and the other parts of the thalli. The δ 13 C values in the sediments varied throughout time (-13‰ to -26‰). The C content was lower in the charophytes than in the angiosperm and there were no large differences among the charophytes. Charophyte fructifications were enriched in organic C compared to the thalli parts. The study provides an isotopic baseline for further studies for the elucidation of higher trophic-level relationships which are particularly complex in shallow water bodies where interactions between the pelagic and the benthic zones are intricate.
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Charophyta: their use in paleolimnology
Journal of Paleolimnology, 1994Co-Authors: Adriana GarciaAbstract:Charophyta are common algae in limnic waters from many regions and are an interesting group from an evolutionary point-of-view, as they are believed to be related to the Chlorophyceae and land plants. Paleontological-botanical systematics are discussed, taking into consideration some new advances. Charophytes live in all types of inland waters and are sensitive to ecological change, and so they are very useful paleolimnological markers. Gaps concerning gyrogonite morphology in extant taxa and their responses to different environmental conditions must be described. This paper discusses data concerning ecological factors affecting the distribution of Argentinian Charophyta (principally distributed between 30°S and 40°S), gyrogonite morphology related to different ecological conditions, and the way that Charophyta can modify the environment.
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quaternary and recent lamprothamnium groves Charophyta from argentina
Hydrobiologia, 1993Co-Authors: Adriana GarciaAbstract:Only recently have extant Lamprothamnium species been reported from the American continent. L. succinctum (A. Br. in Asch.) R. D. W. was found in Lago Titicaca, Bolivia and L. haesseliae Dont. en Laguna Luro and Laguna La Salada, Argentina.
Josep Sanjuan - One of the best experts on this subject based on the ideXlab platform.
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effects of light and temperature on chara vulgaris charophyceae gyrogonite productivity and polymorphism palaeoenvironmental implications
Phycologia, 2017Co-Authors: Alba Vicente, Josep Sanjuan, Nuria Florarnau, Toni Monleon, Jaume Cambra, Carles MartinclosasAbstract:Abstract: To test the influence of light and temperature on intraspecific gyrogonite variation, two common European charophyte species, Chara vulgaris and Chara globularis, were studied indoors under controlled environmental conditions. A total of 60 plants of each species were incubated under different combinations of four irradiances (L1 = 30 μmol PAR m−2 s−1; L2 = 150 μmol PAR m−2 s−1; L3 = 500 μmol PAR m−2 s−1 and L4 = 1000 μmol PAR m−2 s−1) and three water temperatures (T1 = 15°C; T2 = 25°C and T3 = 35°C). These parameters simulate temporary ponds from the Mediterranean region in the summer and help in understanding charophyte reproduction in shallow temporary ponds of past geological periods. After 102 days, gyrogonite productivity was evaluated, and a morphometric analysis of the gyrogonites produced was performed. Our results indicated that both irradiance and water temperature play a key role in C. vulgaris intraspecific gyrogonite variation. Gyrogonites tended to increase their size as irradianc...
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biogeographic history of two eurasian cenozoic charophyte lineages
Aquatic Botany, 2015Co-Authors: Josep Sanjuan, Carles MartinclosasAbstract:Abstract The long-term biogeographic history of charophytes is a highly relevant, although little-studied topic to understand the distribution of extant species. Two contrasting biogeographic histories of Eurasian charophyte lineages are documented and the reasons for such wide distributions are explored. Nitellopsis (Tectochara) merianii–Nitellopsis obtusa is a charophyte lineage ranging from the latest Eocene to the present and displaying Eurasian distribution since the Late Oligocene. Lychnothamnus stockmansii–Lychnothamnus major lineage is defined here as an Eurasian charophyte lineage ranging from the Late Eocene to the Early Oligocene. Both lineages are well documented in the fossil record owing to their applications in stratigraphic dating. The historical biogeography of these lineages displays two opposite patterns. The lineage L. stockmansii–L. major displays an Eurasian distribution from its first occurrence in the Late Eocene, whilst the lineage N. (T.) merianii–N. obtusa underwent a long period of European provincialism ranging from the Late Eocene to the end of the Early Oligocene (an interval of 10 million years, Ma), to begin later, during the Late Oligocene and Miocene, an eastwards expansion until reaching its present Eurasian distribution. These two different biogeographic patterns appear to be related to the contrasting mechanisms of dispersal in monoecious vs dioecious charophytes, well known in extant Chara, and allow us to identify the time needed by characeans to reach supra-continental distributions.
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charophyte palaeoecology in the upper eocene of the eastern ebro basin catalonia spain biostratigraphic implications
Palaeogeography Palaeoclimatology Palaeoecology, 2012Co-Authors: Josep Sanjuan, Carles MartinclosasAbstract:Abstract A micropalaeontological study of the non-marine Upper Eocene of the north eastern Ebro Basin (Catalonia, Spain) was carried out to clarify the palaeoecology of well-known charophyte species that are widely recognised as significant in charophyte biostratigraphy. Autochthonous specimens of the biozone index-species Harrisichara vasiformis-tuberculata were found in marlstones from the Sant Boi Formation (middle part of the Priabonian), which are associated with brackish water ponds laterally related to paralic marshes. In contrast, laterally equivalent assemblages found in white laminated marls from stable freshwater lakes were devoid of the index species and were dominated by Harrisichara lineata. Three more charophyte assemblages are reported from the continental Artes Formation (Stephanochara vectensis biozone, Upper Priabonian). Assemblages dominated by the species Nodosochara jorbae, reported only from Iberia at that age, occur in marlstones related to freshwater, temporary and turbid lakes within flood plains in medial fluvial fan environments. However, Lychnothamnus grambastii dominates locally in similar environments with higher organic matter content. Laterally equivalent assemblages from freshwater perennial lakes in distal alluvial fan facies were dominated by the biozone index-species Harrisichara tuberculata. These results provide evidence that important charophyte index species of the European charophyte biozonation were controlled by palaeoenvironmental factors such as water salinity, lake level changes or terrigenous input to the lakes. In consequence, these species should be used with caution in biostratigraphic studies, taking into account that their presence or absence may be palaeoecologically driven.