Abstract:

1. The coexistence of shrubs and grasses has intrigued ecologists for the past century, and the conundrum of shrub-grass coexistence is at the core of debates on the functioning of semi-arid ecosystems. Here, we explored how the interplay of root competition and facilitation between life-forms at different life stages and demographic bottlenecks controls the long-term coexistence of multiple shrub and grass species in semi-arid Patagonian steppes. 2. We used the spatially explicit and individual-based simulation model DINVEG that integrates the abundant information on the semi-arid Patagonian grass-shrub steppes to test six competing hypotheses on the mechanisms that govern the coexistence and relative abundances of several grass and shrub species. The structurally realistic model allows for a direct comparison of model outputs with a wide range of previously collected field data. 3. We formulate three competing hypotheses on vertical root overlap between grasses and shrubs (no overlap, partial overlap, full overlap) that were crosses with two hypotheses on asymmetric shrub-grass facilitation (with and without). Each of the six variants of DINVEG were tested in their ability to generate dynamics in accordance with detailed field data, and we performed global sensitivity analyses to reveal demographic bottlenecks and controls. 4. The hypothesis combining partial vertical root overlap with no facilitation was the most likely hypothesis given the data. It created demographic bottlenecks in recruitment and emergence that controlled grass and shrub abundances, respectively, and only this hypothesis generated a situation where grasses controlled shrub abundances (by limiting shrub recruitment), but where grass abundance was only weakly controlled by shrubs. Internal water dynamics generated reduced competition of shrubs to neighboured grasses that was sufficient to produce the observed ring of grasses around shrubs, and most of the parameterizations that approximated the observed species-specific abundances were able to reproduce the observed equilibrated spatial patterns of the mature community. 5. Synthesis. We found a complex network of mechanisms that controlled growth-form coexistence and relative abundances in the Patagonian grass-shrub steppe where both, demographic bottlenecks and species interactions across life-forms, species and life stages were important. Our study points to alternative mechanisms of shrub-grass coexistence that may play an important role in dry grasslands and steppes where fire and herbivory are not key drivers and provide an avenue to detect them.

Author affiliation: Cipriotti, Pablo Ariel. Consejo Nacional de Investigaciones Científicas y Técnicas. Oficina de Coordinación Administrativa Parque Centenario. Instituto de Investigaciones Fisiológicas y Ecológicas Vinculadas a la Agricultura; Argentina. Universidad de Buenos Aires. Facultad de Agronomía. Departamento de Métodos Cuantitativos y Sistemas de Información; Argentina

Author affiliation: Aguiar, Martin Roberto. Consejo Nacional de Investigaciones Científicas y Técnicas. Oficina de Coordinación Administrativa Parque Centenario. Instituto de Investigaciones Fisiológicas y Ecológicas Vinculadas a la Agricultura; Argentina. Universidad de Buenos Aires. Facultad de Agronomia. Departamento de Recursos Naturales y Ambiente. Catedra de Ecologia; Argentina

Author affiliation: Wiegand, Thorsten. UFZ Helmholtz Centre for Environmental Research. Department of Ecological Modelling; Alemania

Author affiliation: Paruelo, José. Consejo Nacional de Investigaciones Científicas y Técnicas. Oficina de Coordinación Administrativa Parque Centenario. Instituto de Investigaciones Fisiológicas y Ecológicas Vinculadas a la Agricultura; Argentina. Universidad de Buenos Aires. Facultad de Agronomía. Departamento de Métodos Cuantitativos y Sistemas de Información; Argentina

Abstract:

Question: For a desert where winter is the driest, harshest season we asked: does the effect of dominant shrubs (Bulnesia retama) on annual species depend on (1) the functional traits of the latter, (2) the season of the year, or (3) the activity of livestock? Location: A low-density goat farm in central-northern Monte Desert, Argentina. Methods: We estimated the effect of shrubs using a log response ratio based on annual species population sizes underneath shrub canopies and in open spaces. We collected density data of annual species in 18 visits between Aug 2010 and Apr 2013 in permanent 50-cm square areas laid out according to a split-plot design, in which the activity of livestock (fenced and unfenced; plots were 10-m squares) was the main factor, and microsite type (shrub and open) was the subordinate factor, with 20 replicates for each combination. We also gathered data on eight functional traits (characterizing whole plants, leaves, roots and seeds) from annual plants collected in the study site following standardized protocols. Results: Annual species with acquisitive attributes (high specific leaf area, intermediate-to-low leaf dry matter content, large leaves and high specific root volume) were more benefited by shrubs compared to species with the opposite, relatively conservative attributes. Facilitative influences of shrubs were pervasive during winter, while competitive influences increased in frequency during summer, when total plant density was higher. This pattern was not affected by livestock. Conclusions: The outcome of species interactions depended on the interplay between plant strategies and abiotic stress: facilitated species were mostly acquisitive, and shrub facilitation was more important during the harshest season (winter). Specific root volume, along with widely used functional traits (specific leaf area, leaf dry matter content, leaf size) delineated such strategies. This underlines the importance of considering below-ground traits when studying plant-plant interactions. Single traits achieved superior explanatory power of shrub effects than composite ones (i.e. principal component axes based on single traits), reinforcing the idea that single functional traits are themselves meaningful indicators of complex physiological trade-offs that ultimately affect community structure and dynamics. Whether functional traits determine species' abundance within a given community remains unresolved. We show that ecological strategies of desert annuals determined their abundance in relation to dominant shrubs: acquisitive species were facilitated, whereas conservative ones were repelled. Specific root volume, along with widely used functional traits (specific leaf area, leaf dry matter content, and leaf size) delineated such annual-plant strategies.

Author affiliation: Rolhauser, Andrés Guillermo. Consejo Nacional de Investigaciones Científicas y Técnicas. Oficina de Coordinación Administrativa Parque Centenario. Instituto de Investigaciones Fisiológicas y Ecológicas Vinculadas a la Agricultura. Universidad de Buenos Aires. Facultad de Agronomía. ; Argentina. Universidad Nacional de San Juan. Facultad de Ciencias Exactas, Físicas y Naturales. Departamento de Biología; Argentina

Author affiliation: Pucheta, Eduardo Raúl. Consejo Nacional de Investigaciones Científicas y Técnicas; Argentina. Universidad Nacional de San Juan. Facultad de Ciencias Exactas, Físicas y Naturales. Departamento de Biología; Argentina

Abstract:

In this review, we compiled published results on biological interactions at different spatial scales in the Monte desert of Argentina and identified gaps in current knowledge. We presented evidence of competitive and facilitative plant-plant conspecific and heterospecific interactions, and plant-soil-microbes interactions in relation to the abiotic environment at the fine patch-scale. We also showed evidence of animal-animal interactions and plant-animal interactions at the community scale through study cases involving both native and introduced herbivores. Moreover, we identified bottom-up and top-down forces governing the interactions between granivores (birds, ants, and small mammals) and seed availability/production at the community scale. At the landscape scale, we discussed feedbacks between domestic grazers and the spatial patterns of resources and their interrelationships with processes occurring at other scales. We concluded that research has steadily increased during the last 6 years but knowledge on biological interactions in the Monte desert is still scarce, particularly at a landscape scale.

Author affiliation: Bertiller, Monica Beatriz. Consejo Nacional de Investigaciones Científicas y Técnicas. Centro Científico Tecnológico Conicet - Centro Nacional Patagónico; Argentina. Universidad Nacional de la Patagonia "San Juan Bosco"; Argentina

Author affiliation: Marone, Luis. Consejo Nacional de Investigaciones Científicas y Técnicas. Centro Científico Tecnológico Conicet - Mendoza. Instituto Argentino de Investigaciones de las Zonas Áridas. Provincia de Mendoza. Instituto Argentino de Investigaciones de las Zonas Áridas. Universidad Nacional de Cuyo. Instituto Argentino de Investigaciones de las Zonas Áridas; Argentina. Universidad Catolica de Chile. Center For Advanced Studies In Ecology And Biodiversity; Chile

Author affiliation: Baldi, Ricardo. Consejo Nacional de Investigaciones Científicas y Técnicas. Centro Científico Tecnológico Conicet - Centro Nacional Patagónico; Argentina. Wildlife Conservation Society; Estados Unidos

Author affiliation: Ares, Jorge Oscar. Consejo Nacional de Investigaciones Científicas y Técnicas. Centro Científico Tecnológico Conicet - Centro Nacional Patagónico; Argentina. Wildlife Conservation Society; Estados Unidos

Abstract:

The role of natural enemy diversity in biological pest control has been debated in many studies, and understanding how interactions amongst predators and parasitoids affect herbivore populations is crucial for pest management. In this study, we assessed the individual and combined use of two species of natural enemies, the parasitoid Aphidius ervi Haliday, and the predatory brown lacewing Micromus variegatus (Fabricius), on their shared prey, the foxglove aphid, Aulacorthum solani (Kaltenbach), on sweet pepper. We hypothesized that the presence of intraguild predation (IGP) and predator facilitation (through induced aphid dropping behaviour) might have both negative and positive effects on aphid control, respectively. Our greenhouse trial showed that overall, the greatest suppression of aphids occurred in the treatment with both the parasitoid and the lacewing. While the combination of lacewings and parasitoids significantly increased aphid control compared to the use of parasitoids alone, the effect was not significantly different to the treatment with only predators, although there was a clear trend of enhanced suppression. Thus, the combined effects of both species of natural enemies were between additive and non-additive, suggesting that the combination is neither positive nor negative for aphid control. High levels of IGP, as proven in the laboratory, were probably compensated for by the strong aphid suppression provided by the lacewings, whether or not supplemented with some level of predator facilitation. For aphid management over a longer time scale, it might still be useful to combine lacewings and parasitoids to ensure stable and resilient aphid control.

Author affiliation: Rocca, Margarita. Consejo Nacional de Investigaciones Científicas y Técnicas. Centro Científico Tecnológico Conicet - La Plata. Centro de Estudios Parasitológicos y de Vectores. Universidad Nacional de La Plata. Facultad de Ciencias Naturales y Museo. Centro de Estudios Parasitológicos y de Vectores; Argentina

Author affiliation: Messelink, Gerben J.. University of Agriculture Wageningen; Países Bajos

Abstract:

El género <i>Baccharis</i> presenta una amplia distribución en regiones áridas del noroeste argentino. Una de las especies arbustivas de este género, <i>Baccharis boliviensis</i>, se asocia con diversas plantas en las comunidades vegetales del Parque Nacional Los Cardones en la Provincia de Salta. Estudios realizados sobre la distribución espacial del cardón <i>Trichocereus pasacana</i> con relación al espacio disponible mostraron que, a pesar de que sus semillas son abundantes bajo la copa de <i>Baccharis boliviensis</i>, no se observan plantas creciendo en asociación, a pesar del requerimiento de plantas nodrizas para un establecimiento exitoso del cardón. Extractos acuosos del follaje de <i>Baccharis boliviensis</i>, repartidos en hexano, cloroformo y acetato de etilo, inhibieron la germinación de Trichocereus pasacana</i>. El cloroformo fue el solvente más efectivo para la extracción de los compuestos fitotóxicos. De algunas fracciones de la cromatografía en columna del extracto clorofórmico se aislaron tres flavonoides cuyas estructuras fueron determinadas por métodos espectroscópicos y TLC sobre gel de sílice. Los resultados de los bioensayos mostraron que la germinación de Trichocereus pasacana presentó una respuesta diferencial a los distintos compuestos presentes en las fracciones aisladas del extracto clorofórmico. El efecto inhibidor sólo se presentó en el extracto clorofórmico, lo que sugiere la existencia de un efecto sinérgico o aditivo de los compuestos fitotóxicos.

The genus <i>Baccharis</i> has a wide distribution in the arid regions of Northwestern Argentina. One species of this genus, <i>Baccharis boliviensis</i>, growths in association with other plant species at Los Cardones National Park, Salta Province. Studies carried out on the spatial distribution of the cacti <i>Trichocereus pasacana</i> in relation to available space show that although cacti seeds are abundant beneath <i>Baccharis boliviensis</i> canopy, no adult plants are found growing in association with this species, in spite of the requirement of a nurse plant for a successful cacti establishment. Aqueous extracts from <i>Baccharis boliviensis</i> foliage extracted with hexane, chloroform and ethyl acetate inhibited <i>Trichocereus pasacana</i> germination. Chloroform was the most effective solvent for extracting the phytotoxic compounds. From this extract we isolated three flavonoids whose structures were determined by spectroscopic methods and TLC in silica gel. The germination bioassay showed that <i>Trichocereus pasacana</i> had a differential response to the compounds from the tested extracts. The inhibitory effect was only detected in the chloroformic extract, which suggests a synergistic effect.

Abstract:

Interactions among plants have been hypothesized to be context dependent, shifting between facilitative and competitive in response to variation in physical and biological stresses. This hypothesis has been supported by studies of the importance of positive and negative interactions along abiotic stress gradients (e.g., salinity, desiccation), but few studies have tested how variation in biotic stresses can mediate the nature and strength of plant interactions. We examined the hypothesis that herbivory regulates the strength of competitive and facilitative interactions during succession in Argentinean marshes dominated by Spartina densiflora and Sarcocornia perennis. Spartina densiflora is preferred by the dominant herbivore in the system, the crab Chasmagnathus granulatus. We experimentally manipulated crab herbivory, plant structure, and shade, and we found that, when herbivory was low in the spring and summer, competitive interactions between plants were dominant, but in the fall, when herbivory was highest, facilitative interactions dominated, and Spartina densiflora survival was completely dependent upon association with Sarcocornia perennis. Moreover, experimental removal of Sarcocornia perennis across recently disturbed tidal flats revealed that, while Sarcocornia perennis positively affected small Spartina densiflora patches by decreasing herbivory, as patch size increases and they can withstand the impact of herbivory, competitive interactions predominated and Spartina densiflora ultimately outcompeted Sarcocornia perennis. These results show that herbivory can mediate the balance between facilitative and competitive processes in vascular plant communities and that the strength of consumer regulation of interactions can vary seasonally and with patch size

Author affiliation: Alberti, Juan. Universidad Nacional de Mar del Plata. Facultad de Cs.exactas y Naturales. Departamento de Biología. Laboratorio de Ecología; Argentina. Consejo Nacional de Investigaciones Científicas y Técnicas; Argentina

Author affiliation: Escapa, Mauricio. Universidad Nacional de Mar del Plata. Facultad de Cs.exactas y Naturales. Departamento de Biología. Laboratorio de Ecología; Argentina. Consejo Nacional de Investigaciones Científicas y Técnicas; Argentina. Consejo Nacional de Investigaciones Científicas y Técnicas. Centro Científico Tecnológico Conicet - Bahía Blanca. Instituto Argentino de Oceanografía. Universidad Nacional del Sur. Instituto Argentino de Oceanografía; Argentina

Author affiliation: Iribarne, Oscar Osvaldo. Universidad Nacional de Mar del Plata. Facultad de Cs.exactas y Naturales. Departamento de Biología. Laboratorio de Ecología; Argentina. Consejo Nacional de Investigaciones Científicas y Técnicas; Argentina

Author affiliation: Silliman, Brian Red. University of Florida; Estados Unidos

Author affiliation: Bertness, Mark. University Brown; Estados Unidos

Abstract:

<i>Solanum commersonii</i> es una papa silvestre de notable valor en los programas de mejoramiento de los cultivares de consumo. En los pastizales, esta especie crece asociada a los pajonales de <i>Paspalum quadrifarium</i>, una gramínea manejada con pastoreo. Estamos interesados en saber a) si las plantas de <i>S. commersonii</i> son beneficiadas cuando crecen con las de <i>P. quadrifarium</i>, b) qué efectos produce la defoliación sobre el crecimiento, la reproducción y la supervivencia de las plantas y c) si los atributos vegetativos y reproductivos difieren según los sitios de muestreos. Las semillas de papa fueron colectadas en dos sitios de la Reserva Natural Paititi (Buenos Aires, Argentina), el más bajo y el más alto. Las plantas, una por maceta, fueron cultivadas en condiciones de invernáculo. Se analizaron los efectos de la defoliación, baja y alta intensidad, 50 y 75%, como reducción de la altura de las plantas antes del corte. En condiciones de campo las plantas de <i>S. commersonii</i> fueron cultivadas entre las plantas de un pajonal de <i>P. quadrifarium</i>. Las plantas control crecieron fuera del pajonal, sobre pastos cortos. La defoliación no causó mortalidad de plantas y éstas rebrotaron desde los estolones. La intensidad de la defoliación afectó la biomasa total, de tallos y de hojas. También afectó el área foliar verde y la altura de las plantas. Las plantas de la Cima desarrollaron más área foliar, mayor número de tallos y tubérculos que las plantas de la Colmena. La arquitectura de las plantas de <i>P. quadrifarium</i> generó condiciones ambientales benignas para el crecimiento de <i>S. commersonii</i>, Durante el invierno, la temperatura nocturna fue más baja (heladas) en las condiciones control que en el pajonal. La biomasa aérea muerta de las plantas de papas control fue 67%; en cambio, en las que crecieron en el pajonal fue 13%. El 100% de las plantas control y el 55% de las que crecieron en el pajonal desarrollaron tubérculos. Las bayas sólo fueron producidas en las plantas control, 1.56 y 0.56 g/planta en el sitio más alto y en el más bajo, respectivamente.

<i>Solanum commersonii</i> is a wild potato, valuable as a socioeconomic resource for a breeding program of feeding crops. In grasslands, this species grows associated to <i>Paspalum quadrifarium</i>, a forage grass managed under grazing conditions. We are interested in knowing in <i>S. commersonii</i> plants a) if they are benefitted growing together with <i>P. quadrifarium</i> plants, b) the effects of defoliation on growth, reproduction and survival, and c) if the vegetative and reproductive attributes of the plants differ with sampling site. Potato seeds were collected in two sampling sites of the Paititi Natural Reserve (Buenos Aires, Argentina), the lowest and highest. One potato plant per pot was cultivated. Under greenhouse conditions, it was analyzed the effect of two defoliation intensities, low and high, 50 and 75% plant height reduction compared to pre-defoliation, respectively. Under field conditions, <i>S. commersonii</i> plants were placed among <i>P. quadrifarium</i> tussocks.Control plants were placed outside of the tussocks, on short grass. Defoliation did not cause plant mortality and these regrew through sprouting from stolons. Stems, leaves and total biomass were significantly affected by defoliation intensity. Defoliation intensity also affected green leaves area and height per plant. Plants of the highest site developed more stems and tubers number and green leaves area than from the lowest site. <i>Paspalum quadrifarium</i> architecture generated thermal conditions that were more benign for <i>S. commesonii</i> plant growth. During winter, night temperature was lower (freezing) in control conditions than among tussocks. Shoot dead biomass of the control potato plants was 67% and 13% in the plants growing among <i>P. quadrifarium</i> tussocks. One hundred percent of control plants developed tubers, meanwhile those growing among tussocks only developed the 55%. Berries were only produced in control plants, 1.56 and 0.56 g/plant, in the highest and lowest sites, respectively.

Abstract:

Invasive species threaten native ecosystems worldwide. However, these species can interact positively with local communities, increasing their richness, or the abundance of some species. Many invasive species are capable of influencing the habitat itself, by ameliorating physical stress and facilitating the colonization and survival of other organisms. Barnacles are common engineer species that can change the physical structure of the environment, its complexity, and heterogeneity through their own structure. Balanus glandula is a native barnacle of the rocky shores of the west coast of North America. In Argentina, this invasive species not only colonizes rocky shores but it also has successfully colonized soft-bottom salt marshes, where hard substrata are a limiting resource. In these environments, barnacles form three-dimensional structures that increase the structural complexity of the invaded salt marshes. In this work, we compared the composition, density, richness, and diversity of the macroinvertebrate assemblages associated with habitats of different structural complexity in two Patagonian salt marshes where B. glandula is well established. Our results showed differences in the relative distribution and abundances of the invertebrate species between habitats of different complexities. Furthermore, the response of the communities to the changes in the structural complexity generated by B. glandula was different in the two marshes studied. This highlights the fact that B. glandula facilitates other invertebrates and affect community structure, mainly where the settlement substrata (Spartina vs. mussels) are not functionally similar to the barnacle. Thus, our work shows that the rocky shore B. glandula is currently a critical structuring component of the native invertebrate community of soft-bottom environments where this species was introduced along the coast of southern South America.

Author affiliation: Mendez, María Martha. Consejo Nacional de Investigaciones Científicas y Técnicas. Centro Científico Tecnológico Conicet - Centro Nacional Patagónico. Instituto de Biología de Organismos Marinos; Argentina

Author affiliation: Schwindt, Evangelina. Consejo Nacional de Investigaciones Científicas y Técnicas. Centro Científico Tecnológico Conicet - Centro Nacional Patagónico. Instituto de Biología de Organismos Marinos; Argentina

Author affiliation: Bortolus, Alejandro. Consejo Nacional de Investigaciones Científicas y Técnicas. Centro Científico Tecnológico Conicet - Centro Nacional Patagónico. Instituto Patagónico para el Estudio de los Ecosistemas Continentales; Argentina

Abstract:

Motor facilitation refersto the specific increment in corticospinal excitability (CSE)elicited by the observation of actions performed by others. To date,the precise nature of the mechanism at the basis of this phenomenonis unknown. One possibility is that motor facilitation is driven by apredictive process reminiscent of the role of forward models in motorcontrol. Alternatively, motor facilitation may result from a model-freemechanism by which the basic elements of the observed action aredirectly mapped onto their cortical representations. Our study wasdesigned to discern these alternatives. To this aim, we recorded thetime course of CSE for the first dorsal interosseous (FDI) and theabductor digiti minimi (ADM) during observation of three graspingactions in real time, two of which strongly diverged in kinematicsfrom their natural (invariant) form. Although artificially slow movementsused in most action observation studies might enhance theobserver?s discrimination performance, the use of videos in real timeis crucial to maintain the time course of CSE within the physiologicalrange of daily actions. CSE was measured at 4 time points within a240-ms window that best captured the kinematic divergence from theinvariant form. Our results show that CSE of the FDI, not the ADM,closely follows the functional role of the muscle despite the mismatchbetween the natural and the divergent kinematics. We propose thatmotor facilitation during observation of actions performed in real timereflects the model-free coding of perceived movement following adirect mapping mechanism.

Author affiliation: Gueugneau, Nicolas. Consejo Nacional de Investigaciones Científicas y Técnicas. Oficina de Coordinación Administrativa Houssay. Instituto de Fisiología y Biofísica Bernardo Houssay; Argentina

Author affiliation: Mc Cabe, Sofia Ines. Consejo Nacional de Investigaciones Científicas y Técnicas. Oficina de Coordinación Administrativa Houssay. Instituto de Fisiología y Biofísica Bernardo Houssay; Argentina

Author affiliation: Villalta, Jorge Ignacio. Consejo Nacional de Investigaciones Científicas y Técnicas. Oficina de Coordinación Administrativa Houssay. Instituto de Fisiología y Biofísica Bernardo Houssay; Argentina

Author affiliation: Grafton, Scott T.. University of California. Department of Psychology; Estados Unidos

Author affiliation: Della Maggiore, Valeria Monica. Consejo Nacional de Investigaciones Científicas y Técnicas. Oficina de Coordinación Administrativa Houssay. Instituto de Fisiología y Biofísica Bernardo Houssay; Argentina

Abstract:

In arid environments, direct facilitation (microhabitat amelioration) and indirect facilitation (‘associational resistance’ via protection from herbivory) among plants of different species may act simultaneously. Little is known about their relative effects. One way to disentangle the effects is by evaluating spatial associations. We examined the relative importance of these two mechanisms of facilitation in the semiarid Chaco vegetation of north-central Argentina, through an eight-way observational study in which we quantified the degree of spatial association between saplings of each of two key tree species, Schinopsis lorentzii (Anacardiaceae) and Aspidosperma quebracho-blanco (Apocynaceae), with shrub neighbours either possessing spines or without spines and in both an ungrazed site and a site with a long history of cattle grazing. We analysed data across 400 subparcels at each site with spatial analysis by distance indices. Saplings of both tree species showed positive spatial associations with spiny shrubs in the grazed site but not in the ungrazed site, and never with non-spiny shrubs. This result suggests that spiny shrubs may indeed provide associational resistance for saplings of key tree species in grazed habitats in these dry subtropical forests, that is, that indirect facilitation may predominate over direct facilitation. If confirmed by experimental studies, this result can have implications for the silvopastoral management of rapidly expanding ranches in the semiarid Chaco, where current practice includes the near elimination of native shrubs.

Author affiliation: Tálamo, Andrés. Consejo Nacional de Investigaciones Científicas y Técnicas. Centro Científico Tecnológico Salta. Instituto de Bio y Geociencias del Noroeste Argentino; Argentina

Author affiliation: Barchuk, Alicia. Universidad Nacional de Córdoba. Facultad de Ciencias Agropecuarias; Argentina

Author affiliation: Cardozo, Silvana. Universidad Nacional de Salta. Facultad de Ciencias Naturales; Argentina

Author affiliation: Trucco, Carlos. Universidad Nacional de Salta. Facultad de Ciencias Naturales; Argentina

Author affiliation: Maras, Gustavo. Universidad Nacional de Salta. Facultad de Ciencias Naturales; Argentina

Author affiliation: Trigo, Carolina Beatriz. Consejo Nacional de Investigaciones Científicas y Técnicas. Centro Científico Tecnológico Salta. Instituto de Bio y Geociencias del Noroeste Argentino; Argentina