Historical ecology and current abundance of the translocated Chilla or Grey fox Lycalopex griseus on the large Tierra del Fuego Island shared by Argentina and Chile

In 1951, a batch of 24 young animals of both sexes of Chilla or Grey fox Lycalopex griseus from continental Magallanes region, Chile – and perhaps also from adjacent continental Argentina – were released at Onaisin (65 km ESE Porvenir town, 53°18′S) on Tierra del Fuego Island in southernmost South America, to control a European rabbit (Oryctolagus cuniculus) irruption that was considered detrimental to sheep (Ovis aries) ranching. Up to now, no attention has been paid to the temporal course of that introduction. Here we provide a historical account of the presence of foxes on the Tierra del Fuego Archipelago, starting with Charles Darwin account of 1839 until present. We also review the regulatory framework concerning hunting of those foxes and tally their culling for export of pelts. Finally, we provide estimates of the abundance of Chilla foxes on Tierra del Fuego Island for the period 1999–2007 and for 2021, and highlight their current spread. These translocated foxes have become an abundant and functional part of both steppe and forest ecosystems on the Fuegian archipelago, even though they are killed by hunters, without spatial, temporal, or numerical limits. We conclude that interesting scientific opportunities are being missed regarding the population genetics of a species that may have left founding effects and genetic bottlenecks in Tierra del Fuego, and perhaps some peculiar continental markers among the island population. We also raise the question whether this introduced native species may be deemed invasive, calling for research to determine its impact in its new environment.     

Gastrointestinal helminths of Commerson's dolphins Cephalorhynchus commersonii from central Patagonia and Tierra del Fuego.

The stomachs and intestines of 9 Commerson's dolphins incidentally caught in trawl nets in central Patagonia and 23 stranded on beaches in Tierra del Fuego were surveyed for helminth parasites. A total of 267 individuals belonging to 4 species of parasites (1 nematode, 3 digeneans) were found in the dolphins from the first area: Anisakis sp. (larvae type 1 = A. simplex), Braunina cordiformis, Hadwenius sp. and Pholeter gastrophilus. In the Tierra del Fuego dolphins, 142 specimens belonging to 3 species (2 nematodes, 1 digenean, 1 cestode) were found: A. simplex, Hadwenius sp. and Strobilocephalus triangularis. Only 2 of the helminth species were shared in the 2 study areas, A. simplex and Hadwenius sp., and both were more common in central Patagonia. Among the species, A. simplex was most prevalent and abundant in both study areas. In Tierra del Fuego, adults of A. simplex appeared in only 1 host. Hadwenius sp., P. gastrophilus and S. triangularis are new host records for Commerson's dolphin. Species diversity and species richness were low in both study areas. Helminth communities were more diverse in central Patagonia (t = 1.97, df = 258, p < 0.05) and species richness was higher in central Patagonia (S = 4). No differences in diversity were observed between females and males of central Patagonia (t = 1.97, df = 139, p < 0.05) and between females of central Patagonia and Tierra del Fuego. The results may suggest some differences in habitat use, diet and sex between Commerson's dolphin populations in the 2 study areas.     

Mallomonas madagascariensis, M. lemuriocellata and M. crocodilorum (Synurophyceae), three new species from Madagascar

Hansen, P. & Kristiansen, J. 1995. Mallomonas madagascariensis, M. lemuriocellata and M. crocodilorum (Synurophyceae), three new species from Madagascar. - Nord. J. Bot. 15: 215–223. Copenhagen. ISSN 0107–055X.
Mallomonas madagascariensis, M. lemuriocellata and M. crocodilorum are described and illustrated with TEM micrographs as the first results of studies of silica-scaled chrysophytes made in Madagascar. Their taxonomical position within the genus Mallomonas (sect. Torquatae , ser. Mangoferae ) is discussed and morphological distinguishing characters are presented.     

Trichomycetes living in the guts of aquatic insects of Misiones and Tierra del Fuego, Argentina

Fourteen species of Trichomycetes living in the guts of aquatic insects are reported from two provinces of Argentina, Misiones and Tierra del Fuego. Twelve of the species belong to the Harpellales and two are Amoebidiales. Five harpellid species are reported from Misiones in the extreme northeast of the country (Genistellospora homothallica, Harpella tica, Smittium culisetae, Smittium sp., Stachylina sp.) and seven are from Tierra del Fuego, the southern tip of South America (H. meridianalis, Glotzia sp., S. culicis, S. cellaspora, S. imitatum, Stachylina minima, Penella simulii). Insect hosts all were immature stages of Culicidae, Simuliidae, Chironomidae, Ceratopogonidae (Insecta: Diptera), and Ephemeroptera and Plecoptera. The lower diversity of Trichomycetes found at Misiones, which has a subtropical climate and rainforest vegetation, was due possibly to the warmer temperatures of the water (15-24 C), compared to the colder streams of Tierra del Fuego (9-15 C), with forests and steppes as typical vegetation.     

12. Bipolarity in the distribution of silica-scaled chrysophytes

An investigation of the chrysophyte flora of Tierra del Fuego (Argentina), 54–55 °S., has shown a high degree of similarity with the flora of climatically comparable regions on the northern hemisphere. All the Fuegian species (except two endemic to South America) also occur on the northern hemisphere—some are more or less cosmopolitan, others have pronounced bipolar distributions. Species in common with other Antarctic regions such as Tasmania are all cosmopolitan, and none of the interesting species originally described from Tasmania occur in Tierra del Fuego. Thus the Fuegian flora appears to be mainly climatically determined and a special Antarctic chrysophyte flora does not exist.     

Rhombognathus auster, a new rhombognathine mite (Acari, Halacaridae) from southern South America

A new species of rhombognathine mites. Rhomhognathus auster , is described. The species lives intcrtidally on the shores of eastern Tierra del Fuego. Judging by the shape of idiosoma. legs and claws, R. auster is presumed to live amongst slender, tubular algae in semi-exposcd and sheltered habitats.     

A new species of Penicillium from the Chilean Tierra del Fuego

A new species of Penicillium is described and illustrated. It is represented by two isolates recovered from sandy soils on the shores of Lake Sarmiento, in the Chilean Tierra del Fuego. The new species clearly differs from all species of the genus described so far among the monoverticillate ones, especially by the unique wall ornamentation pattern as viewed with the SEM. It is therefore, described and proposed as a new taxon: Penicillium lacussarmientei sp. nov.     

Craniometric analysis in groups from tierra del Fuego/Patagonia and the peopling of the south extreme of the Americas

Five large craniometric samples from extinct tribes (Selk’nam, Kawéskar and Yámana) from Tierra del Fuego and from Patagonia have been analyzed through multivariate techniques. The purpose was to test the hypothesis of one or two different migration waves in the peopling of the south extreme of South America. A cluster analysis has been made, using the squared Euclidean distance as a measure of proximity, and the UPGMA and neighbor joining algorithms as a tree building method. The robustness of the branches has been assessed with bootstrap analysis through 100 random iterations of the original data set. Results show that, despite their cultural differences, the three hunter-gatherer groups. from Tierra del Fuego tend to cluster together, indicating a similar morphological pattern. This suggests that geographic distance (in latitudinal sense) is the main factor that influenced the differentiation of the human groups from Tierra del Fuego and Patagonia, from a single ancestral population.     

A second, cryptic species of the soft coral genus Incrustatus (Anthozoa: Octocorallia: Clavulariidae) from Tierra del Fuego, Argentina, revealed by DNA barcoding

The encrusting soft coral Incrustatus comauensis is a common denizen of hard substrates in the shallow sub-tidal zone from the central Chilean fjords to the Cape Horn region of southern South America. DNA barcoding of specimens collected from the Beagle Channel, Tierra del Fuego, Argentina, revealed the presence of a second, cryptic species of Incrustatus that is syntopic with I. comauensis. We describe Incrustatus niarchosi, a new species that can be distinguished morphologically from I. comauensis by differences in the microscopic ornamentation of the coenenchymal sclerites. To date, I. niarchosi n. sp. is known only from the Beagle Channel. A population of I. comauensis discovered in the intertidal zone in eastern Tierra del Fuego represents a new record of the species for that habitat and geographic region. Although the intertidal population is also distinct genetically, it is morphologically indistinguishable from sub-tidal Chilean populations of I. comauensis, and at present, there is insufficient evidence to support its status as a separate species.     

SUMMER DISTRIBUTION OF PELAGIC BIRDS OFF THE COAST OF ARGENTINA

Eighteen species of sea–birds were observed from CSS 'Hudson' in the South Atlantic between the Rio de la Plata and Tierra del Fuego in late January and late February 1970. Major feeding areas were noted off Mar del Plata, the Valdes Peninsula and Tierra del Fuego, Argentina, the first two in rich modified or unmodified water of the subantarctic Falkland Current, associated with upwelling. The southernmost area had most birds, the northernmost fewest. A temperate–latitude assemblage including Yellow–nosed Albatross and Cory's Shearwater occurred off Mar del Plata in warmed water of subantarctic (Falkland Current) origin. South of 39°S these two species were replaced by Black–browed Albatross and Great Shearwater in cold offshore water of the Falkland Current. Off the Valdes Peninsula Black–browed Albatross, Great and Sooty Shearwaters, White–chinned Petrels and family groups of Magellanic Penguins occurred near the edge of highly–productive water of the Falkland Current. The largest feeding area, east of Tierra del Fuego, had Magellanic and Rockhopper Penguins, Great Shearwaters, King Cormorants, South American Terns and jaegers, but no oceanographic information is available. At 50°S prions and diving petrels appeared for the first time, marking a possible oceanographic discontinuity or proximity to colonies on the Falkland Islands. Several common species of the South Atlantic were not seen on the transect including Cape Pigeon, Southern Fulmar, Soft–plumaged Petrel, Schlegel's Petrel and Pediunker. Kelp Gull, South American Tern, Manx Shearwater and jaegers were rare or absent far from land. New southern limits for the western South Atlantic Ocean were established for Cory's and Manx Shearwaters, and the Great Shearwater was observed for the first time in Chilean waters.     

Mitochondrial DNA variation and population structure of Commerson’s dolphins (<Emphasis Type="Italic">Cephalorhynchus commersonii</Emphasis>) in their southernmost distribution

The Commerson’s dolphin, Cephalorhynchus commersonii, is found in shallow waters of the continental shelf off the eastern coast of South America between 40°S and 56°S. This species is taken incidentally in artisanal gillnet fisheries, especially along the shallow coastline of northern Tierra del Fuego and southern Patagonia. The biological importance of by-catch is likely to be underestimated if the boundaries of subpopulations are not properly defined. Here, we report on the sequence variation of the mitochondrial DNA control region of the Commerson’s dolphin from five areas defined in Tierra del Fuego, Argentina and Chile, to provide a preliminary assessment of population structure where conservation efforts are most needed. A 466 bp fragment of the mitochondrial DNA control region was sequenced from 196 samples of skin, teeth and bone, defining 20 haplotypes from 17 polymorphic sites. Nucleotide (π = 0.40%) and haplotype (h = 0.807) diversity were low compared to some other odontocete populations, but similar to that of other species of this genus. Genetic differentiation evaluated through analyses of molecular variance (AMOVA) showed significant overall differences among areas within Tierra del Fuego (Φ _ST  = 0.059, P < 0.01). An analysis of sex-specific population structure suggested that the dispersal rates of both females and males are low, indicative of females displaying greater site fidelity. The results from mtDNA control region sequences alone revealed significant differentiation among studied areas, which should be considered as independent management units. We recommend that the impact of localized gillnet mortalities should be managed on a local scale in these areas of Tierra del Fuego.     

Spiders from Beauchêne Island, Falkland Islands, South Atlantic

A collection of 55 spiders, which was made on Beauchêne Island, Falkland Islands archipelago, in December 1980, contains seven species. Three of these are known from the main body of the Falkland Islands, one is a new subspecies of a species previously known from Patagonia and Tierra del Fuego, and the remaining three are endemic to Beauchêne Island. New taxa described are Auximus fuegianus bransfieldi nssp. and Emmenomma beauchenicum n.sp.     

Two new species of Penicillium from the Tierra del Fuego (Argentina and Chile)

Two new species of Penicillium Link ex Fries are described and illustrated. They were recovered from sandy soils in the Chilean and Argentinian Tierra del Fuego. They clearly differ from all species of the genus described so far and are, therefore, described and proposed as two new taxa: Penicillium turris-painensis sp. nov and Penicillium lapatayae sp. nov.     

Pleistocene refugia and polytopic replacement of diploids by tetraploids in the Patagonian and Subantarctic plant Hypochaeris incana (Asteraceae, Cichorieae)

We report the phylogeographic pattern of the Patagonian and Subantarctic plant Hypochaeris incana endemic to southeastern South America. We applied amplified fragment length polymorphism (AFLP) and chloroplast DNA (cpDNA) analysis to 28 and 32 populations, respectively, throughout its distributional range and assessed ploidy levels using flow cytometry. While cpDNA data suggest repeated or simultaneous parallel colonization of Patagonia and Tierra del Fuego by several haplotypes and/or hybridization, AFLPs reveal three clusters corresponding to geographic regions. The central and northern Patagonian clusters (∼38–51° S), which are closer to the outgroup, contain mainly tetraploid, isolated and highly differentiated populations with low genetic diversity. To the contrary, the southern Patagonian and Fuegian cluster (∼51–55° S) contains mainly diploid populations with high genetic diversity and connected by high levels of gene flow. The data suggest that H. incana originated at the diploid level in central or northern Patagonia, from where it migrated south. All three areas, northern, central and southern, have similar levels of rare and private AFLP bands, suggesting that all three served as refugia for H. incana during glacial times. In southern Patagonia and Tierra del Fuego, the species seems to have expanded its populational system in postglacial times, when the climate became warmer and more humid. In central and northern Patagonia, the populations seem to have become restricted to favourable sites with increasing temperature and decreasing moisture and there was a parallel replacement of diploids by tetraploids in local populations.     

Assessing genetic variation and population structure of invasive North American beaver (<Emphasis Type="Italic">Castor Canadensis</Emphasis> Kuhl, 1820) in Tierra Del Fuego (Argentina)

The North American beaver (Castor Canadensis) was introduced into Isla Grande de Tierra del Fuego, Argentina in 1946 as a potential source of wild fur. The species showed high growth potential, reaching close to 100,000 individuals from an original founding stock of 25 females and 25 males. Beavers adapted rapidly to their new environment and became invasive, providing an excellent model of successful adaptation of introduced populations to a new habitat. In this study, we used polymorphic mitochondrial (mt) DNA to evaluate genetic variation in the introduced beaver population from Tierra del Fuego. Nucleotide variation in partial sequences of Cytochrome b (500 bp) and 12S rRNA (421 bp) genes and the main non-coding D-loop region (521 bp) were analyzed. Our study allowed to identify 10 different mtDNA lineages in the invasive population, none of them shared among the source populations. The pattern observed is a consequence of cessation of gene flow following expansion of the founding beaver population since the time of its introduction. This approach contributes to the understanding of effects of genetic changes on survival ability and reproductive success of invasive species. It also has important management implications to invasive species.     

Morphological variation and ecology of Mallomonas crassisquama (Chrysophyceae)

Siver, P. A. & Skogstad, A. 1988. Morphological variation and ecology of Mallomonas crassisquama (Chrysophyceae). - Nord. J. Bot. 7: 99–107. Copenhagen. ISSN 0107–055X.
Mallomonas crassisquama is one of the most common and widely distributed species of Mallomonas . In this study we compare the morphology and ecology of the species based on 309 collections from 67 localities in Connecticut (U.S.A.) and Norway. The taxon produces a very complex siliceous coat consisting of four scale and two bristle types all of which have considerable structural variation. A new variety, M. crassisquama var. papillosa is described. Bristle production was found to be temperature dependent where cells formed serrated or helmet bristles under cold or warm conditions, respectively. M. crassisquama was found to exist over wide temperature, conductivity, phosphorus and pH ranges, however, was absent in samples with a pH <5.5.     

A new species of Oxelytrum Gistel (Coleoptera, Silphidae) from southern Argentina, with a key to the species of the genus

A new species of the forensically interesting genus Oxelytrum Gistel (Coleoptera, Silphidae), Oxelytrum selknan, is described from Santa Cruz and Tierra del Fuego provinces, Argentina. The new species resembles Oxelytrum biguttatum (Philippi) in outer aspect, but has different male genitalia, in particular a median lobe longer than the paramera. All the described species of Oxelytrum have the median lobe shorter than the paramera. The internal sac, as far as it could be reconstructed from dry-pinned specimens, also shows differences between the two species. A key to the species of Oxelytrum is given and illustrated.     

Two new African species of Lejeuneaceae

Abstract

At present, the available information about the liverworts of Sphagnum magellanicum Brid. mires from South America is very limited. The main aim of this paper is to present a comprehensive study of the liverwort flora of this habitat, as well as details on the chorology and ecology of the taxa involved. Four different environmental units were examined, based on the water table level and plant cover, in three representative raised bogs from Tierra del Fuego National Park Ushuaia. Floristic relevs were recorded in 93 square plots 050050m², distributed at random in the environmental units. Twentyfour liverwort species have been identified the majority have a Subantarctic distribution and there were a remarkable number of Magellanean endemics 11 species. Among the rare species, there were two new records for the Argentinian Province of Tierra del Fuego, Cephaloziella byssacea and Chiloscyphus notophyllus. The ecological preferences of the species were analysed based on their frequencies in the four environmental units examined. Only six species demonstrated significant correlation with some of the environmental units. Riccardia pallidevirens, R. georgiensis, R. alcicornis, and Cephaloziella varians, showed a preference for waterlogged and wet habitats, while Calypogeia sphagnicola and Cephalozia chilensis were linked to dense carpets of Sphagnum magellanicum.