Alejandro R. Giraudo

Categorización del estado de conservación de los anfibios de la República Argentina

Through the participation of nine specialists from different institutions from all over Argentina and after more than a decade from the first Red List of threatened herpetofauna proposed by Asociacion Herpetologica Argentina in 2000, we assessed the conservation status of the argentine Testudines taxa, adding the new taxonomic, biological and ecological knowledge progresses made since then as well as applying methodological changes in the former assessment. As a result from the 14 turtles taxa recognized as present in Argentina, nine were included in the actual Red List under some degree of risk (three Critically Endangered, three Endangered, three Vulnerable). From the remaining ones, three were classified as Insufficiently Known and two as Not Threatened. In the classification of the three marine turtles that are frequently found in argentine coasts we adopted the IUCN (2011) Red List criteria. In relation with the former categorization, we included a new species registered in Argentina (Phrynops geoffranus, Insufficiently Known), added two synonymies, increased from one to three the species within

Detecting areas of endemism with a taxonomically diverse data set: plants, mammals, reptiles, amphibians, birds, and insects from Argentina

The idea of an area of endemism implies that different groups of plants and animals should have largely coincident distributions. This paper analyses an area of 1152 000 km2, between parallels 21 and 32°S and meridians 70 and 53°W to examine whether a large and taxonomically diverse data set actually displays areas supported by different groups. The data set includes the distribution of 805 species of plants (45 families), mammals (25 families), reptiles (six families), amphibians (five families), birds (18 families), and insects (30 families), and is analysed with the optimality criterion (based on the notion of endemism) implemented in the program NDM/VNDM. Almost 50% of the areas obtained are supported by three or more major groups; areas supported by fewer major groups generally contain species from different genera, families, or orders.

Biología reproductiva de la serpiente semiacuática Liophis semiaureus (Serpentes, Colubridae) en el nordeste de Argentina

Las serpientes tienen una notable flexibilidad y diversidad en sus tacticas reproductivas, a pesar de ello, los estudios acerca de la biologia reproductiva de especies sudamericanas en zonas subtropicales-templadas son escasos. Se analizo la biologia reproductiva de Liophis semiaureus en el nordeste de Argentina, incluyendo la madurez y dimorfismo sexual, fecundidad y ciclo reproductivo. Las hembras maduras fueron significativamente mas largas, presentaron mayor peso corporal y alcanzaron la madurez sexual a una longitud mayor que los machos. Los machos tuvieron colas mas largas que las hembras. El ciclo reproductivo fue estacional con mayor actividad en los periodos templados del ano aunque previos a la epoca de inundaciones. Liophis semiaureus invirtio mas energia en la reproduccion que en el crecimiento, lo que posibilita que comiencen a reproducirse con tamanos mas pequenos con respecto a otras poblaciones, sin retrasar su reproduccion hasta alcanzar mayores tamanos. Esta puede ser una estrategia ventajosa en climas estacionales. Las caracteristicas reproductivas y de dimorfismo sexual en L. semiaureus se encontrarian influenciadas por aspectos filogeneticos, geograficos y ecologicos, lo que determina que la especie responda de manera general al patron reproductivo del grupo taxonomico pero con particularidades propias determinadas por los factores geograficos y los requerimientos ecologicos.

The genera Boiruna and Clelia (serpentes: pseudoboini) in Paraguay and Argentina

Snakes of the pseudoboine genera Clelia, which is probably polyphyletic, and Boiruna are distributed from southern Argentina, southern Brazil, and Uruguay northwards into central Mexico. Six members occur in Paraguay and Argentina: B. maculata, Clelia bicolor, C. clelia, C. plumbea, C. quimi, and C. rustica. Historically, there has been taxonomic confusion among the larger species (B. maculata, C. clelia, C. plumbea, and C. rustica) and between the small species (C. bicolor and C. quimi). All of the species except C. rustica have distinct ontogenetic color changes. Species can be distinguished on the bases of size, color, hemipenial spines, and loreal, supralabial, and ventral scale counts. Much of the morphological evolutionary differentiation in Boiruna and Clelia seems to have taken place in the snout region, as evidenced by the differing proportions of the scales of the loreal region. Boiruna maculata has the widest ecological amplitude. It is broadly distributed in most vegetation types north of the 38th parallel in central Argentina, being absent only from the deltaic sediments of Buenos Aires Province, Argentina and the broad valleys and rolling hills of eastern Paraguay. Clelia bicolor is most common in the Paraguay and Parana river valleys, with a few records from the Andean foothills in northern Argentina. Clelia clelia is distributed along the Rio Paraguay and the lower Parana, and is also found throughout much of eastern Paraguay. Clelia plumbea is apparently parapatric with C. clelia along the Rio Parana in southeastern Paraguay and Misiones Province, Argentina. The ranges of C. quimi to the east and C. bicolor in the west about in this same region without apparent overlap. There are no vouchered records of Clelia rustica from Paraguay. In Argentina, it is a species of temperate climates; north of the 30th parallel, it occurs in the Andean foothills and the wet forests of Misiones Province. Southwards, it is widely distributed to beyond the 40th parallel.

Temperate snake community in South America: is diet determined by phylogeny or ecology?

Communities are complex and dynamic systems that change with time. The first attempts to explain how they were structured involve contemporary phenomena like ecological interactions between species (e.g., competition and predation) and led to the competition-predation hypothesis. Recently, the deep history hypothesis has emerged, which suggests that profound differences in the evolutionary history of organisms resulted in a number of ecological features that remain largely on species that are part of existing communities. Nevertheless, both phylogenetic structure and ecological interactions can act together to determine the structure of a community. Because diet is one of the main niche axes, in this study we evaluated, for the first time, the impact of ecological and phylogenetic factors on the diet of Neotropical snakes from the subtropical-temperate region of South America. Additionally, we studied their relationship with morphological and environmental aspects to understand the natural history and ecology of this community. A canonical phylogenetical ordination analysis showed that phylogeny explained most of the variation in diet, whereas ecological characters explained very little of this variation. Furthermore, some snakes that shared the habitat showed some degree of diet convergence, in accordance with the competition-predation hypothesis, although phylogeny remained the major determinant in structuring this community. The clade with the greatest variability was the subfamily Dipsadinae, whose members had a very different type of diet, based on soft-bodied invertebrates. Our results are consistent with the deep history hypothesis, and we suggest that the community under study has a deep phylogenetic effect that explains most of the variation in the diet.

How do demographic and social factors influence parent‐offspring conflict? The case of wild black and gold howler monkeys (Alouatta caraya)

In this study, we examined the influence of demography and social context on mother‐offspring conflict in wild black and gold howler monkeys (Alouatta caraya) inhabiting two nearby sites in northern Argentina, one comprising continuous forest and one fragmented forest. These sites differed in population density (3.25 vs. 1.04 individuals/ha), degree of home range overlap between neighboring groups (70 vs. 31%), and rate of intergroup encounters (2 vs. 0.02‐1 encounters/day), though not in interbirth interval or rate of infant mortality. During a 27‐month study (September 2008 through November 2010), we observed 37 mother‐offspring dyads across the two sites. We found a very similar pattern of mother‐offspring conflict in both populations; specifically, the sites did not differ in any of the variables used to characterize the mother‐offspring relationship (the time spent in contact, the rate at which the mother makes and breaks contact, the rate at which the infant breaks contact, the rate of maternal rejection, and signs of infant distress) except one (the rate at which the infant makes contact). Although mother‐offspring conflict is a dynamic process that varies over time, our results suggest that the different demographic and social contexts found at the two study sites did not have a marked effect on quantitative aspects of the mother‐offspring relationship in these populations of black and gold howlers. Finally, this study suggests that the environmental variability (ecological, demographic, and social traits) leads to a set of strategies used both by infants and mothers with a main goal of conflict resolution, with mothers specifically aiming to cope with the tradeoff between current and future reproduction. Am. J. Primatol. 77:911–923, 2015.

Las especies amenazadas como hipótesis: problemas y sesgos en su categorización ejemplificados con las serpientes de la Argentina

Threatened species are those that have a high probability of extinction or are close to this situation to continue direct pressure on them or their habitats. From this definition we analyze problems and biases in the categories of threat of Argentine snakes, showing examples where taxonomic changes (Linnaean shortfall), gaps in knowledge about the distribution of species (Wallacean shortfall), or bio-ecological aspects (Haeckelean shortfall) generate biases in the allocation of its conservation status. We proposed that endangered species should be listed as hypothesis, by analyzing scientifically quantitative and / or qualitative information about its geographic distribution, size and population trend and bio-ecological characteristics that make them vulnerable against anthropogenic effects. As a result, will be reject or not its

Is xenodontine snake reproduction shaped by ancestry, more than by ecology?

Abstract One of the current challenges of evolutionary ecology is to understand the effects of phylogenetic history (PH) and/or ecological factors (EF) on the life‐history traits of the species. Here, the effects of environment and phylogeny are tested for the first time on the reproductive biology of South American xenodontine snakes. We studied 60% of the tribes of this endemic and most representative clade in a temperate region of South America. A comparative method (canonical phylogenetic ordination—CPO) was used to find the relative contributions of EF and PH upon life‐history aspects of snakes, comparing the reproductive mode, mean fecundity, reproductive potential, and frequency of nearly 1,000 specimens. CPO analysis showed that PH or ancestry explained most of the variation in reproduction, whereas EF explained little of this variation. The reproductive traits under study are suggested to have a strong phylogenetic signal in this clade, the ancestry playing a big role in reproduction. The EF also influenced the reproduction of South American xenodontines, although to a lesser extent. Our finding provides new evidence of how the evolutionary history is embodied in the traits of living species.

Descriptive bioregionalisation and conservation biogeography: what is the true bioregional representativeness of protected areas?

Abstract. Conservation biogeography involves the application of biogeographical principles and methods to conservation issues, including the design of protected areas. Bioregionalisation has been central in the implementation of main global conservation strategies, providing the basis for prioritising protected areas and evaluating their representativeness and effectiveness in conservation actions. Traditionally, experts established these bioregionalisations without repeatable methodologies and using only qualitative evidence, which has set constraints in their usefulness. We compared three descriptive bioregionalisations commonly used for conservation decision-making, with a regionalisation produced using quantitative methods (endemicity analysis), so as to assess biases and differences in the representativeness of the existing protected-area system of Argentina. Areas of endemism were detected using NDM/VNDM quantitative methodology on a database consisting of 19 250 distribution records of 116 taxa of snakes, and the results were compared with previous descriptive regionalisations. We recovered 9 quantitative bioregionalisation units (QBU) v. 6–8 descriptive bioregionalisation units (DBU) proposed by previous authors. From this comparison, the following was found: (1) we discovered three new QBU not considered by any previous DBU; (2) other three areas proposed by DBU are not supported by our endemicity analysis; (3) we detected differences comparing the representativeness of protected areas between descriptive v. quantitative bioregionalisations, leaving the first, some areas of conservation relevance largely unprotected. Moreover, DBU were characterised by a high degree of uncertainty and biases, such as the consideration of probably artificial units, the non-recognition of some natural units and mistakes in the representativeness of protected areas. We emphasise the importance of applying quantitative biogeographic methods to identify bioregionalisation units and its fundamental role in conservation biogeography so as to optimise protected-area efficiency and other territorial conservation strategies.

Distribution and natural history notes on Tachymenis chilensis chilensis (Schlegel, 1837) (Reptilia: Serpentes: Dipsadidae) in Argentina

We revisit the distribution and natural history data of Tachymenis chilensis chilensis (Schlegel, 1837) in Argentina based on compiled and novel records, extending its northern and southern distribution from the previously known localities in Argentina. We recorded two prey items in Argentinean populations: Rhinella rubropunctata , reported for the first time, and Liolaemus pictus . Tachymenis c. chilensis is mainly found in forested habitats, generally near wetlands with abundant populations of amphibians. The latitudinal range occupied by T. c. chilensis in Argentina is similar to that in Chile, but its northern distribution limit reaches the lowest latitudes in Chile. This is probably due to the higher humidity levels in the western slopes of the Andes and the barrier effect of the highest mountain ranges in this area.