Systematic studies of the antarctic species of the Phyllophoraceae (Gigartinales, Rhodophyta) based on rbcL sequence analysis

The Antarctic biota has evolved over the last 100 million years in increasingly isolated and cold conditions. As a result, Antarctic species, from micro-organisms to vertebrates, have adapted to life at extremely low temperatures, including changes in the genome, physiology and ecological traits such as life history. Coupled with cycles of glaciation that have promoted speciation in the Antarctic, this has led to a unique biota in terms of biogeography, patterns of species distribution and endemism. Specialization in the Antarctic biota has led to trade-offs in many ecologically important functions and Antarctic species may have a limited capacity to adapt to present climate change. These include the direct effects of changes in environmental parameters and indirect effects of increased competition and predation resulting from altered life histories of Antarctic species and the impacts of invasive species. Ultimately, climate change may alter the responses of Antarctic ecosystems to harvesting from humans. The unique adaptations of Antarctic species mean that they provide unique models of molecular evolution in natural populations. The simplicity of Antarctic communities, especially from terrestrial systems, makes them ideal to investigate the ecological implications of climate change, which are difficult to identify in more complex systems.

Download Full-text

The molecular systematics of some agar- and carrageenan-containing marine red algae based on rbcL sequence analysis

Fifteenth International Seaweed Symposium ◽

10.1007/978-94-009-1659-3_17 ◽

1996 ◽

pp. 125-135

Author(s):

Suzanne Fredericq ◽

Max. H. Hommersand ◽

D. Wilson Freshwater

Keyword(s):

Sequence Analysis ◽

Molecular Systematics ◽

Red Algae ◽

Rbcl Sequence

Download Full-text

Recent developments in the systematics of the Gigartinaceae (Gigartinales, Rhodophyta) based on rbcL sequence analysis and morphological evidence

Phycological Research ◽

10.1111/j.1440-1835.1999.tb00294.x ◽

1999 ◽

Vol 47 (3) ◽

pp. 139-151 ◽

Cited By ~ 39

Author(s):

Max H. Hommersand ◽

Suzanne Fredericq ◽

D. Wilson Freshwater ◽

Jeffery Hughey

Keyword(s):

Sequence Analysis ◽

Morphological Evidence ◽

Rbcl Sequence ◽

Recent Developments

Download Full-text

Phylogeny of the Eocene Antarctic Tapetinae Gray, 1851 (Bivalvia, Veneridae) from the La Meseta and Submeseta formations

Journal of Paleontology ◽

10.1017/jpa.2020.30 ◽

2020 ◽

Vol 94 (5) ◽

pp. 799-818

Author(s):

Maximiliano Jorge Alvarez ◽

Claudia Julia del Río

Keyword(s):

Phylogenetic Analysis ◽

New Species ◽

New Genus ◽

Late Eocene ◽

New Combination ◽

New Genera ◽

Systematic Analysis ◽

Antarctic Species ◽

The Antarctic ◽

First Time

AbstractSystematic analysis shows that the Southern Hemisphere bivalve genus Retrotapes includes the Antarctic species R. antarcticus, R. newtoni, and R. robustus and recognizes for the first time the presence of Katelysia represented by K. florentinoi. Two new genera were erected in this study: Marciachlys new genus to include M. inflata new combination, and Adelfia new genus, which includes A. austrolissa new combination and A. omega new species from the Eocene of Antarctica, and the late Eocene Chilean A. arenosa new combination. Eurhomalea carlosi was synonymized with K. florentinoi; Cyclorismina marwicki with R. antarcticus; Gomphina iheringi was considered an indeterminate species; and Cockburnia lunulifera was excluded from the Tapetinae. These systematic assignments are supported by a phylogenetic analysis, which recognizes an Austral clade of Tapetinae, comprising all the genera mentioned above, along with Marcia, Paleomarcia, Atamarcia, and Protapes.UUID: http://zoobank.org/a8c91a9f-99ec-4235-8416-d398771a3eb2

Download Full-text

Phylotypic Characterization of Mycobionts and Photobionts of Rock Tripe Lichen in East Antarctica

Microorganisms ◽

10.3390/microorganisms7070203 ◽

2019 ◽

Vol 7 (7) ◽

pp. 203 ◽

Cited By ~ 2

Author(s):

Merry Sailonga Faluaburu ◽

Ryosuke Nakai ◽

Satoshi Imura ◽

Takeshi Naganuma

Keyword(s):

Green Algae ◽

Phenotypic Variability ◽

Antarctic Species ◽

Green Algal ◽

The Common ◽

Valley Site ◽

The Antarctic ◽

Specially Protected Areas ◽

High Diversity

Saxicolous rock ripe lichens that grow on rocks in the East Antarctic fellfields were sampled for phylotypic characterization of its constituent mycobionts (fungi) and photobionts (algae and cyanobacteria). The rock tripe lichen-forming fungal and algal phylotypes were classified under the common lichen-forming genera of ascomycetes, namely, Umbilicaria, and green algae, namely, Trebouxia and Coccomyxa. However, phylotypes of the green algal chloroplasts and the lichen-associated cyanobacteria showed unexpectedly high diversity. The detected chloroplast phylotypes were not fully affiliated with the green algal genera Trebouxia or Coccomyxa. The predominant chloroplast phylotype demonstrated maximum resemblance to Neglectella solitaria, which is neither a known Antarctic species nor a typical lichen photobiont. Another dominant chloroplast phylotype belonged to the atypical Antarctic green algae family. Cyanobacterial phylotypes were dominated by those affiliated with the Microcoleus species rather than the well-known lichen-associates, Nostoc species. The occurrences of these Microcoleus-affiliated cyanobacterial phylotypes were specifically abundant within the Yukidori Valley site, one of the Antarctic Specially Protected Areas (ASPA). The ASPA site, along with another 50 km-distant site, yielded most of the cryptic diversity in the phylotypes of chloroplasts and cyanobacteria, which may contribute to the phenotypic variability within the rock tripe lichen photobionts.

Download Full-text

Zoogeography of the Antarctic ascidian fauna in relation to the sub-Antarctic and South America

Antarctic Science ◽

10.1017/s0954102007000521 ◽

2007 ◽

Vol 19 (3) ◽

pp. 321-336 ◽

Cited By ~ 25

Author(s):

Carmen Primo ◽

Elsa Vázquez

Keyword(s):

South America ◽

Saint Paul ◽

South American ◽

South American Species ◽

Species Classification ◽

Antarctic Region ◽

Antarctic Species ◽

Tristan Da Cunha ◽

Centre Of Origin ◽

The Antarctic

AbstractThis study of the relationships between the Antarctic, sub-Antarctic and South America biogeographical regions used both existing and new data. We constructed a presence/absence matrix of 237 species for 27 biogeographical divisions which included the Amsterdam-Saint Paul and Tristan da Cunha islands. Species and areas were classified using cluster analysis combined with MDS ordination. Six main groups were obtained from the species classification: 1) Amsterdam-Saint Paul, and 2) Tristan da Cunha species, 3) species from the Macquarie Province, 4) species from the sub-Antarctic Region, 5) Antarctic species and species distributed in the cold regions, 6) South American species. The biogeographical components were dominated by the endemic (although it is not as high as in other groups), Antarctic-South America and Southern Hemisphere elements. Except for Amsterdam-Saint Paul, Tristan da Cunha and Bouvet, the areas considered were grouped together with Macquarie being rather related to New Zealand regions. We speculate that the Antarctic Region may have acted as an “evolutionary incubator”, providing a centre of origin for sub-Antarctic and South American ascidians.

Download Full-text

A new species of Acarospora (Acarosporaceae, Acarosporales, lichenized Ascomycota) from the Falkland Islands (Islas Malvinas)

Phytotaxa ◽

10.11646/phytotaxa.340.1.7 ◽

2018 ◽

Vol 340 (1) ◽

pp. 86 ◽

Cited By ~ 1

Author(s):

DAG O. ØVSTEDAL ◽

LOUISE LINDBLOM ◽

KERRY KNUDSEN ◽

ALAN M. FRYDAY

Keyword(s):

New Species ◽

Molecular Data ◽

Falkland Islands ◽

Antarctic Species ◽

Islas Malvinas ◽

The Antarctic ◽

A New Species

Acarospora malouina Øvstedal & K. Knudsen is described from the Falkland Islands. It is morphologically very similar to the Antarctic species A. gwynnii but differs in chemistry, ecology and evidence from molecular data.

Download Full-text

Distinguishing between two Antarctic species of Eocene Palaeeudyptes penguins: a statistical approach using tarsometatarsi

Polish Polar Research ◽

10.2478/popore-2013-0020 ◽

2013 ◽

Vol 34 (3) ◽

pp. 237-252 ◽

Cited By ~ 12

Author(s):

Piotr Jadwiszczak ◽

Carolina Acosta Hospitaleche

Keyword(s):

Statistical Approach ◽

Finite Mixture Model ◽

Species Boundaries ◽

Size Distributions ◽

Antarctic Species ◽

Clustering Techniques ◽

Significant Challenge ◽

Principal Coordinates ◽

Fuzzy Partitioning ◽

The Antarctic

AbstractDefining species boundaries, due to morphological variation, often represents a significant challenge in paleozoology. In this paper we report results from multi− and univariate data analyses, such as enhanced clustering techniques, principal coordinates or− dination method, kernel density estimations and finite mixture model analyses, revealing some morphometric patterns within the Eocene Antarctic representatives of Palaeeudyptes penguins. These large−sized birds were represented by two species, P. gunnari and P. klekowskii, known mainly from numerous isolated bones. Investigations focused on tarso− metatarsi, crucial bones in paleontology of early penguins, resulted in a probability−based framework allowing for the “fuzzy” partitioning the studied specimens into two taxa with partly overlapping size distributions. Such a number of species was supported by outcomes from both multi− and univariate studies. In our opinion, more reliance should be placed on the quantitative analysis of form when distinguishing between species within the Antarctic Palaeeudyptes.

Download Full-text