Mammalian Carnivore Coprolites from the Sopas Formation (Upper Pleistocene,Lujanian Stage), Uruguay

Continental tetrapod coprolites from Uruguay are described for the first time. These remains come from the Piedra Pintada locality (Artigas Department), northern Uruguay, where the Sopas Formation crops out (Upper Pleistocene, Lujanian Stage). It was possible to identify several attributes indicative of a coprolitic origin, such as anisopolar shape, extrusion marks, pointed ends, sutures, gas bubbles, and inclusions. These specimens are assigned to carnivorous mammals, probably large felids, based on morphological attributes and inclusions of rodent bones and teeth.     

Potential effects of physiological plastic responses to salinity on population networks of the estuarine crab <Emphasis Type="Italic">Chasmagnathus granulata</Emphasis>

Chasmagnathus granulata is a South American crab occurring in estuarine salt marshes of the Brazilian, Uruguayan and Argentine coasts. Life history is characterized by an export strategy of its larval stages. I reviewed information on experimental manipulation of salinity during embryonic and larval development (pre- and posthatching salinities), and on habitat characteristics of C. granulata in order to determine potential effects of larval response to salinity in the field and to suggest consequences for the population structure. Local populations are spread over coastal areas with different physical characteristics. Benthic phases occupy estuaries characterized by different patterns of salinity variation, and release larvae to coastal waters characterized by strong salinity gradients. The zoea 1 of C. granulata showed a strong acclimatory response to low salinity. This response operated only during the first weeks of development (during zoeae 1 and 2) since subsequent larval survival at low posthatching salinities was consistently low. Larvae developing at low salinity frequently followed a developmental pathway with five instead of four zoeal stages. The ability to acclimate and the variability in larval development (i.e. the existence of alternative developmental pathways) could be interpreted as a strategy to buffer environmental variability at spatial scales of local or population networks. Early survivorship and production of larvae may be relatively high across a rather wide range of variability in salinity (5–32‰). Plastic responses to low salinity would therefore contribute to maintain a certain degree of population connectivity and persistence regardless of habitat heterogeneity. Electronic Publication     

Genetic characterisation of the intermediate hosts of schistosomiasis in its southern distribution limit in South America

ABSTRACT

Schistosomiasis is a tropical disease caused by the digenean parasite Schistosoma mansoni. In South America it is transmitted to humans via freshwater snails of the genus Biomphalaria. In a global warming scenario, disease range expansions to subtropical countries are possible. For the first time, the distributions and genetic identification of Biomphalaria specimens in border regions of Uruguay are reported. The inclusion of Uruguayan samples allows a better understanding of the relationships between and within taxa of Biomphalaria. Samples were collected between 2015 and 2016 using hand nets. Initially, they were classified morphologically. They were then classified genetically by analysing a fragment of the cytochrome c oxidase subunit I gene. Phylogenetic analysis revealed the presence of B. peregrina and B. occidentalis. Species belonging to the B. tenagophila complex were also recognised. Individuals initially identified from their external morphology as B. tenagophila tenagophila showed inconsistencies with the analysis of COI sequences that assigned them to B. occidentalis. Since the presence of schistosomiasis in Uruguay is likely to occur in the next few years, an exhaustive population survey of Biomphalaria taxa should be urgently developed to identify the presence of S. mansoni and the places most susceptible to be colonised by these snails.     

Phylogenetic relationships of species of Crenicichla (Teleostei: Cichlidae) from southern South America based on the mitochondrial cytochrome b gene

Phylogenetic analysis using Bayesian inference, likelihood and parsimony methods was conducted on 60 complete mitochondrial cytochrome b sequences from 21 species of Crenicichla, including all species known from Uruguay (Crenicichla celidochilus, Crenicichla lepidota Crenicichla minuano, Crenicichla missioneira, Crenicichla punctata, Crenicichla scottii, Crenicichla vittata), Crenicichla compressiceps, Crenicichla empheres, Crenicichla geayi, Crenicichla iguassuensis, Crenicichla macrophthalma, Crenicichla menezesi, Crenicichla notophthalmus, Crenicichla regani, Crenicichla cf. regani, Crenicichla semifasciata, Crenicichla sveni, Crenicichla tendybaguassu, two unidentified species, and also two species of Teleocichla. Bayesian analysis resulted in a trichotomy with three major groups: (1) The C. missioneira species group (C. celidochilus, C. empheres, C. minuano, C. missioneira, C. tendybaguassu, and an undescribed species analyzed); (2) a group of southern species (C. iguassuensis, C. punctata, C. scottii, C. vittata); and (3) a rather heterogeneous group comprising the type species C. macrophthalma, members of the Crenicichla reticulata species group (C. geayi, C. semifasciata), members of the Crenicichla wallacii species group (C. compressiceps, C. notophthalmus, C. regani, C. cf. regani), members of the Crenicichla saxatilis species group (C. lepidota, C. menezesi, C. sveni, C. sp.), and two species of Teleocichla. Parsimony jackknifing resulted in a quadritomy with: (1) C. macrophthalma, (2) Teleocichla, (3) the saxatilis + wallacii group species, and (4) the rest, which include C. geayi and C. semifasciata as sister group to a dichotomy with the C. missioneira group and the remaining southern species. The sequence variation within the C. missioneira group is remarkably minor despite considerable morphological differences, supporting the conclusion that it forms an endemic species flock in the Uruguay River basin. Previously proposed species groups within the speciose genus Crenicichla (more than 90 species known) are partly corroborated. However, C. celidochilus was not previously associated with the C. missioneira species group, and C. vittata has not previously been associated with C. scottii, C. iguassuensis, or C. punctata. Crenicichla lepidota, C. sveni, C. menezesi and C. sp. represent the C. saxatilis group. Species of small size, representing the C. wallacii species group and Teleocichla are characterized by very long branches, and the position of Teleocichla differed considerably between the Bayesian and parsimony trees. This finding does not invalidate Teleocichla but rather suggests that the several monophyletic major clades within Crenicichla may need nominal recognition. A putative hybrid specimen with a morphology combining components from C. vittata and C. scottii, but with a cytochrome b sequence from C. scottii was found in a sample from the Rio Quaraí/Cuareim. Another putative hybrid specimen with a unique morphology but a cytochrome b sequence agreeing with C. scottii was found in a sample from Maldonado, but no other Crenicichla species than C. scottii is known from that locality.     

Food habits of the Broad‐snouted Caiman (Caiman latirostris: Crocodylia,Alligatoridae) in northwestern Uruguay

The food habits of the Broad‐snouted Caiman (Caiman latirostris) were studied in northwestern Uruguay. The most common prey were insects, the shrimp Pseudopalaemon bouvieri, the snail Pomacea canaliculata, fish and birds. Spiders, crabs, amphibians, snakes, turtles and mammals were consumed less frequently. Arthropods were the most frequent prey for juvenile caiman. Fish and snails were consumed by all size classes. The proportion of stomach contents with invertebrates decreased with increasing caiman size, and that with vertebrates was greater in the diet of larger caiman. Diet composition and ontogenetic shift are similar to that of other crocodilians considered as opportunistic generalist predators.

Se estudiaron los hábitos alimenticios del Yacaré (Caiman latirostris) en el noroeste de Uruguay. Las presas más comunes fueron insectos, el camarón Pseudopalaemon bouvieri, el caracol Pomacea canaliculata, peces y aves. Arañas, cangrejos, anfibios, serpientes, tortugas y mamíferos fueron consumidos menos frecuentemente. Los artrópodos fueron las presas más frecuentes de juveniles. Peces y aves fueron consumidos por todos los tamaños. La proporción de contenidos estomacales con invertebrados disminuyó al aumentar el tamaño de los caimanes, y la de vertebrados fue mayor en los individuos de mayor tamaño. La composición y cambio ontogenético en la dieta resultan similares a los de crocodilianos considerados predadores generalistas oportunistas.     

The impact of the International Atomic Energy Agency (IAEA) program on radiation and tissue banking in Uruguay: development of tissues quality control and quality management system in the National Multi-Tissue Bank of Uruguay

BNOT was created and regulated in 1977 and started its operation in 1978 according to the Decree No. 86/1977. By the Decree 248/005 is transformed in the National Institute of Donation and Transplantation of Cells, Tissues and Organs (Instituto Nacional de Donación y Trasplante de Células, Tejidos y órganos—INDT). The organisation has been operating within the State University Medical School and the Public Health Secretary and it is the governmental organisation responsible for the regulation, policy and management of donation and transplantation in Uruguay. By the Decree 160/2006 is responsible for human cells and tissues regulation too. The participation of the INDT in the IAEA program facilitated the introduction of the radiation sterilisation technique for the first time in the country. The radiation sterilisation of tissues processed by INDT (ex BNOT), was initially carried out in the 60 Cobalt Industrial Plant in the National Atomic Energy Commission of Argentina and now is carried out in INDT, using a Gamma Cell 220 Excel, which was provided by the IAEA through the national project URU/7/005. The results of the implementation of tissues, quality control and quality management system, are showed.     

The evolution of the Uruguayan population

Uruguay is usually considered an immigrants' country that, unlike other South American countries, has no native population and only a slight African contribution. The perception of its identity frequently refers to this characteristic: there are no regional differences and population variability is minimal. The object of this paper is to analyze the processes that shaped the present population and the regional diversity in their historical context. For this purpose parish and civil archives of three Departments were reviewed for the period 1840–1990: Cerro Largo and Tacuarembo, in the Northeast and Montevideo, in the south. The origin of the population, individual migration distance, consanguinity and marriage age were taken into account. With the exception of age, differences were found between the capital, Montevideo, and the Northeast for the selected variables during most of the period analyzed. On the basis of these results, the importance of Montevideo as the point of entry of both immigrants and slaves, the regional homogeneity and the concept of national identity are discussed.