Patagonian Species Research Articles

A trip of a bamboo lifetime: tracing the origin and evolution of Chusquea (Poaceae, Bambusoideae, Bambuseae) in Patagonia, southernmost South America

Abstract We performed a phylogenetic analysis with estimated clade ages and an ancestral-range estimation focused on the Patagonian species of Chusquea, i.e. the Chusquea culeou clade, to unravel their biogeographical history. Phylogenetic analyses were conducted with sequence data from four plastid markers, using maximum parsimony and Bayesian inference approaches. The complete sampling and addition of the Patagonian Chusquea species into a phylogenetic framework revealed the most likely origin and evolutionary history of the Chusquea culeou clade. The Patagonian Chusquea originated roughly 11.35 Mya, most likely from a common ancestor from the Atlantic Forest region, when this lineage underwent in situ diversification and its species evolved sympatrically. All the extant species have arisen in the last 8 Myr. Moreover, according to the present sampling, the most recent common ancestor of subtribe Chusqueinae originated in the Northern Andes, which is also the most common source area of the estimated dispersal events. Some other preliminary insights on the biogeographic history of the genus are included.

Carex recondita Muñoz-Schüler, Martín-Bravo & Jim.Mejías (Carex section Junciformes Kük., Cyperaceae), a new sedge species from the Andes of central Chile

Carex section Junciformes is one of the most diverse groups of the genus in South America, consisting of approximately 30 species. Here we describe a new species, Carex recondita, belonging to this section. We studied its placement within a molecular phylogeny of the group and found it to constitute an independent lineage. The new species is morphologically very close to C. austroamericana, from southern Patagonia, despite being phylogenetically divergent to the rest of Patagonian species of sect. Junciformes. So far, this species is known only from a few specimens recently collected in its type locality, despite growing in a well-collected area in the Andes of Metropolitana Region of Santiago, the most populated administrative region of Chile. We provide a detailed morphological description, comments on its relationship with other Southern Cone species of sect. Junciformes and relevant ecological notes.

REVISITING THE CRETACEOUS LUNGFISH <em>ATLANTOCERATODUS IHERINGI</em> (AMEGHINO 1898) FROM THE MATA AMARILLA FORMATION (ARGENTINA) WITH COMMENTS ON TOOTH PLATES HISTOLOGY

Atlantoceratodus iheringi (Ameghino 1898) from Argentine territory is restudied based on its known tooth plates and newly discovered material, which includes previously unknown skull roof bones and vomerine tooth plates. The latter represent the first records of such elements from the Mesozoic era in South America. The comparative morphological analysis reveals its distinctiveness from other dipnoans, and offers valuable data for future systematic and phylogenetic research. The pterygopalatine tooth plates display narrow-based first denticulations and lack anterior wear facets, with the inner angle positioned at the level of the second denticulation. Similarly, the prearticular tooth plates feature straight mediolingual edges, and a wide-based first denticulation without sinuosities at the tip. Histological sections are performed and analyzed in detail for the first time. A. iheringi presents in this aspect distinctive features such as: large-lumen denteons tending to cluster together, circumdenteonal dentine arranged in a double band (an inner birefringent and an outer monorefringent), and a disordered interdenteonal dentine, with birefringence surrounding denteons and areas with monorefringence. A. iheringi exhibits histological structure closer to Mesozoic and Cenozoic dipnoans than Paleozoic, especially resembling the disposition observed in the Upper Cretaceous Patagonian species Metaceratodus baibianorum. The wide distribution of features designated as diagnostic for Atlantoceratodus is discussed.

Stand development stages and recruitment patterns influence fine-scale spatial genetic structure in two Patagonian Nothofagus species

Key messageNothofagus alpina (Poepp. et Endl.) Oerst. and Nothofagus obliqua (Mirb.) Oerst forests have strong fine-scale spatial genetic structures. The intensity of genetic structure patterns differed according to species, stand development stages, life stages, and spatial arrangement of regeneration groups. This data becomes useful for forest management as it provides an understanding of how populations evolve as well as of the consequences of disturbances and enables the establishment of sampling strategies.ContextThe understanding of fine-scale spatial genetic structure in natural populations is useful for forest management. Although Nothofagus alpina (Poepp. et Endl.) Oerst. and N. obliqua (Mirb.) are important species of the Patagonian forest, little is known about the genetic structure of their populations.AimsThe main objectives were to investigate the differences in fine-scale spatial genetic structure among mature tree populations of both species considering two stands at different development stages. Genetic structure was also evaluated among life stages and spatial distribution groups of regeneration within the old-growth stand.MethodsGenetic structure was examined by microsatellite DNA analysis of regeneration and mature tree populations of both species (around 1300 individuals). Gene dispersal distance was additionally estimated.ResultsIn both stands and species, strong fine-scale spatial genetic structure and short dispersal distance were found. This pattern was stronger in the early successional forest, in N. obliqua populations, in earlier life stages, and in scattered regeneration.ConclusionStand development stages and recruitment patterns influence the fine-scale spatial genetic structure of both Nothofagus species. However, the genetic structure also differs between species.

How much does Chemotaxonomy help to resolve the overrepresented Cycadolepis Saporta (Bennettitales)? A case study of the Cretaceous of Patagonia, Argentina

The spectroscopic characterization of five species belonging to Cycadolepis Saporta is used to obtain new insights into the utilization of functional groups as chemotaxonomic parameters. The Cycadolepis spp. remains, collected from the Springhill Formation (Hauterivian–Barremian; Santa Cruz Province, Argentina), are sterile scale-leaves, which are interpreted to be part of a hypothetical megasporangiate cone of the Order Bennettitales. The materials consist of five scale-leaves with very well-preserved cuticles, which are studied by means of Fourier Transform Infrared (FTIR) spectroscopy. For this purpose, two sample forms are defined: 1) compressions), and 2) cuticles. The semi-quantitative derived data are evaluated through Principal Component Analysis (PCA) revealing the functional groups preserved for each Cycadolepis taxon. The PCA results indicate that the Cycadolepis spp. show similar chemical compositions regardless of the taxon, whereas the cuticle chemistry reveals a relatively high contribution of aromatic structures and variable contribution of oxygen-containing compounds. The latter is presumably a consequence of mainly phenylpropanoids and aromatic domains composing biomacropolymers. The IR-data reveal slight differences among the five species of Cycadolepis despite the distinctive morpho-anatomical patterns shown by the epidermis of each taxon. However, although preliminary, the first analysis of functional groups as an additional taxonomic parameter to those morphoanatomical are encouraging and contribute to a better understanding of the chemical composition and the probable relationship of the five Patagonian species of Cycadolepis, a genus which is known by its peculiar variability. Could these results suggest that some of the five species of Cycadolepis belong to a unique megasporangiate cone?

Variability in fruit traits and anthocyanin content among and within populations of underutilized Patagonian species Berberis microphylla G. Forst.

BACKGROUND: The Berberis microphylla (calafate) is an evergreen shrub considered a non-timber product from the Patagonian forest, relevant for the diversification of agrifood production, particularly interesting since its black–blue fruits are extremely rich in phenolic compounds. OBJECTIVE: The main objectives were to: (1) quantify the variability of fruit traits, anthocyanin content, efficiency of the reproductive shoots and leaf nutrient content within the set of 34 B. microphylla wild accessions from Tierra del Fuego Island, Argentina, (2) calculate the coefficients of correlation between variables and (3) detect relationships between the genotypes. METHODS: Plants growing near Ushuaia city (n = 12), bordering Fagnano lake (n = 12) and central area of the Tierra del Fuego Island (n = 10) were selected. RESULTS: A significant variability in fruit traits, anthocyanin content and the efficiency of reproductive shoots among and within the three populations was assessed, a result with great relevance for breeding purposes. Phenotypic plasticity was related with the environmental conditions, i.e. air temperatures for each population during the three monitored growing seasons. CONCLUSIONS: Overall, results indicate that yearly environmental factors play a relevant role in phenotypic variation of both individual plants and populations, thus confirming the complexity of wild species evolution and domestication processes.

Sobran cuchillos, falta el pescado. Auge del langostino patagónico y reactivación del conflicto social en Mar del Plata

En los últimos años, las poblaciones de langostino crecieron inusitadamente promoviendo que una buena parte de la flota fresquera y merlucera que tradicionalmente operaba en Mar del Plata se reorientara hacia esta especie de localización patagónica. El presente trabajo, apunta a demostrar que mientras las exportaciones pesqueras nacionales marcan récords históricos, la conflictividad social en la formación social y espacial pesquera de Mar del Plata se ha revitalizado motivada por la falta de pescado fresco descargado en tierra. En este sentido, analizamos: la evolución de las descargas de merluza y langostino en el país; el comportamiento de las distintas flotas y las características y recurrencia de la conflictividad social en Mar del Plata. A tales fines, trabajamos con bibliografía específica, estadísticas oficiales, prensa periódica, publicaciones especializadas del sector pesquero y entrevistas a informantes calificados.

Cretaceous–Paleogene plant extinction and recovery in Patagonia

AbstractThe Cretaceous–Paleogene (K/Pg) extinction appears to have been geographically heterogeneous for some organismal groups. Southern Hemisphere K/Pg palynological records have shown lower extinction and faster recovery than in the Northern Hemisphere, but no comparable, well-constrained Southern Hemisphere macrofloras spanning this interval had been available. Here, macrofloral turnover patterns are addressed for the first time in the Southern Hemisphere, using more than 3500 dicot leaves from the latest Cretaceous (Maastrichtian) and the earliest Paleocene (Danian) of Argentine Patagonia. A maximum ca. 90% macrofloral extinction and ca. 45% drop in rarefied species richness is estimated across the K/Pg, consistent with substantial species-level extinction and previously observed extirpation of host-specialized leaf mines. However, prior palynological and taxonomic studies indicate low turnover of higher taxa and persistence of general floral composition in the same sections. High species extinction, decreased species richness, and homogeneous Danian macrofloras across time and facies resemble patterns often observed in North America, but there are several notable differences. When compared with boundary-spanning macrofloras at similar absolute paleolatitudes (ca. 50°S or 50°N) from the Williston Basin (WB) in the Dakotas, both Maastrichtian and Danian Patagonian species richnesses are higher, extending a history of elevated South American diversity into the Maastrichtian. Despite high species turnover, our analyses also reveal continuity and expansion of leaf morphospace, including an increase in lobed and toothed species unlike the Danian WB. Thus, both Patagonian and WB K/Pg macrofloras support a significant extinction event, but they may also reflect geographically heterogeneous diversity, extinction, and recovery patterns warranting future study.

Notocotylus chionis (Trematoda: Notocotylidae) and Notocotylus sp. from shorebirds in southern Patagonian wetlands of Argentina: morphological and molecular studies

Southernmost South America provides significant wintering habitats for migrant shorebirds, most of which breed in the High Arctic tundra. Helminth species parasitizing these migratory birds have been well studied in North America; however, in South America they are poorly known. As part of an ongoing research on the helminth fauna from Patagonian birds in Argentina, we report Notocotylus chionis and Notocotylus sp. (Trematoda: Notocotylidae) parasitizing three shorebird species, the Nearctic migrants Calidris fuscicollis (WRSA) and Calidris bairdii (BASA) (Scolopacidae), and the Neotropical Charadrius falklandicus (TBPL) (Charadriidae). We provide a new morphological description of N. chionis considering that the previous one reported from the snowy sheathbill on Subantarctic islands are incomplete and based on few specimens. We also provided a morphometric characterization of Notocotylus sp. We obtained molecular data which confirmed the identification of specimens recovered from WRSA and TBPL as N. chionis. Phylogenetic analysis based on 28S ribosomal DNA sequences was performed. The results placed N. chionis close to other Patagonian species native to South America (i.e. N. primulus). Notocotylus chionis was found previously in the snowy sheathbill which inhabits in coasts of southern South America, Antarctic Peninsula and surrounding islands. Present finding in resident birds (TBPL) allows us to hypothesize that N. chionis is a Neotropical species whose life cycle is being completed in southern South America and Subantarctic islands and represents a valuable contribution to the knowledge of parasite diversity in the austral subpolar region of the western hemisphere.

Phylogenetic analysis of the winter and southernmost scorpion genus Urophonius (Bothriuridae), with the description of two new Patagonian species

The first phylogenetic analysis of genus Urophonius is performed based on morphological characters. Three monophyletic species groups are recovered. Species of the granulatus species group and Urophonius mondacai have summer or spring activity patterns. The exochus and brachycentrus species groups form a monophyletic group with a winter activity pattern, which is so far unique in scorpions from temperate and cold areas. Additionally, two new Patagonian species of Urophonius are described, one from Argentina and one from Chile. Finally, we discuss the southernmost distributions of scorpions in continental Patagonia. We suggest that the southern limit of the group could be related not only with a decrease in temperature, but also with an increase of precipitation.

Bovista pezica (Basidiomycota, Agaricales) – A new species with unusually ornamented capillitium, from Patagonia Argentina

Collections of the genus Bovista in southern South America have been traditionally identified under northern-hemisphere names. Although many puffball species show a wide distribution, the identity and distribution of Patagonian species still need to be revisited. Recent materials collected in Patagonia and displaying a unique capillitium ornamented with oblique membranes are shown here to correspond to a new species, Bovista pezica, from the Nothofagaceae forests. An unusually thick and coriaceous endoperidium also supports the separation of these specimens verified by our molecular analyses. We present here a full description of B. pezica sp. nov. along with a key for the species recorded in Patagonia, and we discuss the possible distributional range.

Staying close: short local dispersal distances on a managed forest of two Patagonian Nothofagus species

Abstract Understanding the impact of management on the dispersal potential of forest tree species is pivotal in the context of global change, given the implications of gene flow on species evolution. We aimed to determine the effect of logging on gene flow distances in two Nothofagus species from temperate Patagonian forests having high ecological relevance and wood quality. Therefore, a total of 778 individuals (mature trees and saplings) of Nothofagus alpina and N. obliqua, from a single plot managed 20 years ago (2.85 hectares), were mapped and genotyped at polymorphic nuclear microsatellite loci. Historical estimates of gene dispersal distance (based on fine-scale spatial genetic structure) and contemporary estimates of seed and pollen dispersal (based on spatially explicit mating models) were obtained. The results indicated restricted gene flow (gene distance ≤ 45 m, both pollen and seed), no selfing and significant seed and pollen immigration from trees located outside the studied plot but in the close surrounding area. The size of trees (diameter at breast height and height) was significantly associated with female and/or male fertility. The significant fine-scale spatial genetic structure was consistent with the restricted seed and pollen dispersal. Moreover, both estimates of gene dispersal (historical and contemporary) gave congruent results. This suggests that the recent history of logging within the study area has not significantly influenced on patterns of gene flow, which can be explained by the silviculture applied to the stand. The residual tree density maintained species composition, and the homogeneous spatial distribution of trees allowed the maintenance of gene dispersal. The short dispersal distance estimated for these two species has several implications both for understanding the evolution of the species and for defining management, conservation and restoration actions. Future replication of this study in other Nothofagus Patagonian forests would be helpful to validate our conclusions.

Cortinarius section Thaumasti in South American Nothofagaceae forests

ABSTRACTWe studied the South American species of Cortinarius section Thaumasti based on morphological and molecular data. Members of this group can easily be identified in the field because the basidiomata are small and Phlegmacium-like with a bulbous stipe and the universal veil in most species forms a distinct volva at the base of the stipe. The phylogenetic delimitation of the clade was mostly in concordance with the earlier, morphology-based grouping of the South American taxa except that C. chrysophaeus was resolved outside of the clade. Altogether nine species were recognized in the section. Four species, C. chlorophanus, C. coleopus, C. cosmoxanthus, and C. vaginatus, were previously described by other authors, whereas three species, C. chlorosplendidus, C. olivaceovaginatus, and C. subcosmoxanthus, are described here as new. We were able to identify two remaining taxa, but we do not have sufficient morphological data to allow for a formal description. All of the species in C. section Thaumasti form ectomycorrhizal associations with Nothofagaceae. They have been documented from South America and New Zealand. The Patagonian species are considered endemic to the region. A key to the described species is provided.

Invasive species and postglacial colonization: their effects on the genetic diversity of a Patagonian fish.

The present distribution of Patagonian species is the result of a complex history involving Quaternary refugial populations, Holocene range expansions and demographic changes occurring during the Anthropocene. Invasive salmonids were introduced in Patagonia during the last century, occupying most rivers and lakes, preying on and competing with native species, including the fish Galaxias platei. Here, we used G. platei as a case study to understand how long-term (i.e. population differentiation during the Holocene) and short-term historical processes (salmonid introductions) affect genetic diversity. Using a suite of microsatellite markers, we found that the number of alleles is negatively correlated with the presence of salmonids (short-term processes), with G. platei populations from lakes with salmonids exhibiting significantly lower genetic diversity than populations from lakes without salmonids. Simulations (100 years backwards) showed that this difference in genetic diversity can be explained by a 99% reduction in population size. Allelic richness and observed heterozygosities were also negatively correlated with the presence of salmonids, but also positively correlated with long-term processes linked to Quaternary glaciations. Our results show how different genetic parameters can help identify processes taking place at different scales and their importance in terms of conservation.

Typification of names and nomenclatural notes on the South Andean and Patagonian species of Polygala Linnaeus (Polygalaceae)

As part of an ongoing revision of the genus Polygala, several names of the South Andean and Patagonian species in need of nomenclatural and taxonomic study were identified. 13 lectotypes have been designated for accepted names, synonyms and a dubious taxon.

Reproductive Biology of the Critically Endangered Valcheta Frog,Pleurodema somuncurense(Anura: Leptodactylidae), from Patagonia, Argentina

Fil: Velasco, Melina Alicia. Consejo Nacional de Investigaciones Cientificas y Tecnicas; Argentina. Universidad Nacional de la Plata. Facultad de Ciencias Naturales y Museo. Division Zoologia de Vertebrados. Seccion Herpetologia; Argentina

Seed germination of five Prosopis shrub species (Fabaceae-Mimosoideae) from the Monte and Patagonia phytogeographic provinces of Argentina

The Patagonian species of the genus Prosopis exhibit distinctive features such as their shrub growth pattern. However, morphological or physiological differences among them have been poorly studied (e.g., germination). Considering this lack of information, we studied five Prosopis species from two different phytogeographic provinces: Monte and Patagonia. Particularly, we focused on the southern area of the Monte province and the Payunia District of the Patagonian province. We evaluated the effects of pre-germination treatments such as acid scarification using two different exposure times on these Prosopis species. The effectiveness of the treatments was related to the phytogeographic origin of the shrubs. The endemic species of Payunia District (Patagonia phytogeographic province) required longer times of acid scarification than those from the southern area of the Monte. In general, acid scarification resulted in high and homogeneous germination percentages. Our results provide useful information that contributes to improve the protocols necessary for the production of a high number of seedlings, which is required for successful restoration projects.

New Anatomical Data on Pyrotherium (Pyrotheriidae) from the Late Oligocene of Mendoza, Argentina

Fil: Cerdeno Serrano, Maria Esperanza. Consejo Nacional de Investigaciones Cientificas y Tecnicas. Centro Cientifico Tecnologico Conicet - Mendoza. Instituto Argentino de Nivologia, Glaciologia y Ciencias Ambientales. Provincia de Mendoza. Instituto Argentino de Nivologia, Glaciologia y Ciencias Ambientales. Universidad Nacional de Cuyo. Instituto Argentino de Nivologia, Glaciologia y Ciencias Ambientales; Argentina

Status of the names of some hydroid species (Cnidaria, Hydrozoa), described from the Atlantic coast of Patagonia.

Thirty new species of benthic leptothecate hydroids were described and named from Patagonia in a 1991 PhD dissertation by Mohamed El Beshbeeshy. Although constituting nomina nuda under provisions of the International Code of Zoological Nomenclature (ICZN), the names of some species were used in several scientific publications between 1991 and 2011. In 2011, the dissertation of El Beshbeeshy was published in accordance with Article 8 of the ICZN. Several species-group names appearing in that work nevertheless fail to fully comply with certain articles of the code. The goal of this contribution is to review the nomenclatural availability of the names of those 30 new taxa, and to clearly establish the current status of El Beshbeeshy's material. Two of them were made available in 1999 as part of studies other than those of El Beshbeeshy, and correct authorship and date is here noted. Twenty-one of the nomina nuda were made available in a work published by El Beshbeeshy in 2011, although some constitute junior synonyms. Six of the new species-group names appearing in both the 1991 and 2011 works, established following a literature review of Patagonian species, were proposed without re-description, or designation of name-bearing types, or locations of such types. Most of them do not meet criteria of availability and remain nomina nuda. The status of each is discussed to avoid additional nomenclatural errors and continued taxonomic confusion.

Reassessment of Neovenericor Rossi de García, Levy & Franchi, 1980 (Bivalvia: Carditidae) using a geometric morphometric approach, and revision of planicostate carditids from Argentina

Pérez, D.E., Alvarez, M.J. & Santelli, M.B., July 2016. Reassessment of Neovenericor Rossi de García, Levy & Franchi, 1980 (Bivalvia: Carditidae) using a geometric morphometric approach, and revision of planicostate carditids from Argentina. Alcheringa 41, xxx–xxx. ISSN0311-5518.Various systematic approaches have been applied to the Neogene planicostate carditids of Patagonia. Some authors have included these species within Venericor (known from the Eocene of North America and Europe) or in Megacardita (recorded from the Miocene of Europe). By contrast, Rossi de García et al. erected the endemic Neovenericor in 1980 for Patagonian species. The three proposed genera have variable outlines and similar hinge teeth configuration. Two geometric morphometric analyses were performed, which included the type species of the following taxa: M. jouanneti (middle Miocene, Mediterranean Basin), V. planicosta (middle Eocene, Paris Basin) and N. austroplata (early Miocene, Chenque Formation, Chubut Province). In the first approach, an Elliptic Fourier Analysis was used to test the general variability of outlines. In the second, a landmark-based method was employed to analyse the hinge configuration, followed by a Discriminant Function Analysis. The outline analysis discriminated Megacardita from the other two taxa based on its more elongate and rectangular shells. The Landmark Analysis distinguished the three taxa based on both, left and right hinges. The Discriminant Function Analysis showed significant values for this differentiation. Neovenericor has a higher hinge plate, broader and less posteriorly inclined teeth, and a less sinuous ventral edge than Megacardita; and it has larger and more posteriorly inclined teeth than Venericor. Other morphological characters of the genus include an intermediate number of radial ribs that do not dissipate ventrally, and wide and deep intercostal spaces. Thus, Neovenericor is clearly a distinct taxon. All Argentinian planicostate carditids were revised and included in this genus because they embrace its diagnostic features.Damián E. Pérez [trophon@gmail.com], Maximiliano J. Alvarez [maxialvarez82@gmail.com] and M. Belén Santelli [mbsantelli@gmail.com], Museo Argentino de Ciencias Naturales Bernardino Rivadavia, División Paleoinvertebrados, Av. Ángel Gallardo 470 (C1405DJR), Buenos Aires, Argentina.