Vanished Lagoa Santa: rodent species loss in the last two centuries

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The extensive work developed by Peter Lund and other naturalists in the nineteenth century in Lagoa Santa Karst has generated a large volume of data on the extinct and extant local fauna. Despite these classic pioneer works, little work has been done about the fauna currently present in the region. Therefore, this study analyzes the richness and diversity of the modern fauna of small rodents of the Lagoa Santa region and compares the results with the historical data of Lund and Winge. We collected owl pellets from calcareous caves in Lagoa Santa, Cordisburgo and Sete Lagoas. These pellets were divided in two categories for comparison: “superficial” (collected on the surface of the cave floor) and “stratified” (collected in small excavations in the cave floor). We identified a total of 18 rodent species: 13 Cricetidae, 3 Echimyidae and 2 Muridae. Richness considering the minimum number of individuals (MNI) was greater in “stratified” samples than in “superficial” samples, but the two sets of samples did not differ when considering rarefaction. According to the Shannon-Wiener and Pielou indices, the “stratified” samples were more diverse and with less species dominance. Nine species mentioned or described by Lund and Winge in the nineteenth century as inhabiting this region were absent in our samples. The proportion of small mammals in owl pellets in the modern samples was different from historical data, with predominance of Calomys spp. instead of Necromys lasiurus, as recorded by Lund using similar methods. It is likely that human activities in the region over these 180 years have influenced the fauna of Lagoa Santa, triggering local or regional extinctions.


Lagoa Santa devastada: perda das espécies de roedores nos últimos dois séculos. O extenso trabalho desenvolvido por Peter Lund e outros naturalistas no século XIX no Carste de Lagoa Santa gerou um enorme volume de dados sobre a fauna local extinta e existente. Apesar destes trabalhos pioneiros clássicos, pouco se sabe sobre a fauna atual na região. Portanto, este estudo analisa a riqueza e diversidade da fauna moderna de pequenos roedores da região de Lagoa Santa e compara os resultados com os dados históricos obtidos por Lund e Winge (1836). Para isso, foram coletadas pelotas de coruja em cavernas calcáreas em Lagoa Santa, Cordisburgo e Sete Lagoas. As amostras foram divididas em duas categorias: “superficial” (coletadas na superfície do chão das cavernas) e “estratificada” (coletadas em pequenas escavações do chão das cavernas). Um total de 18 espécies de roedores foram identificados: 13 Cricetidae, 3 Echimyidae e 2 Muridae. A riqueza foi maior nas amostras “estratificadas” quando comparadas no mesmo MNI com amostras “superficiais”, mas não diferiram na análise de rarefação. De acordo com os índices Shannon-Wiener e Pielou, a “estratificada” foi considerada mais diversificada e com menor predominância de espécies. Nove espécies mencionadas ou descritas por Lund e Winge no século XIX como habitando a região foram ausentes em nossas amostras. A proporção de pequenos mamíferos nas amostras modernas foi diferente dos dados históricos, com predominância de Calomys spp. em vez de Necromys lasiurus, conforme registrado por Lund por métodos similares. É provável que as atividades humanas na região ao longo desses 180 anos tenham influenciado a fauna de Lagoa Santa, provocando extinções locais ou regionais.

Distribución geográfica de Calomys musculinus (Rodentia, Sigmodontinae) en Patagonia

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El objetivo de este trabajo es documentar —sobre la base de información tanto publicada como inédita— la distribución geográfica del sigmodontino Calomys musculinus en Patagonia. Se compilaron 165 localidades de ocurrencia de las cuales 104 son novedosas. La especie se distribuye ampliamente en Patagonia. Su rango geográfico coincide, en el nordeste, con la Provincia Fitogeográfica del Monte; hacia el sur y oeste se asocia con ambientes de la franja costera y los principales valles fluviales, respectivamente. En los últimos cientos de años las poblaciones de C. musculinus han experimentado incrementos locales dramáticos, cuya vinculación con el establecimiento de oasis agrícolas resulta plausible.


Geographic distribution of Calomys musculinus (Rodentia, Sigmodontinae) in Patagonia. The aim of this paper is to document—based on both published and unpublished data—the geographical distribution of Calomys musculinus in Patagonia. We compiled 165 recording localities of which 104 are new. The species is widely distributed in Patagonia. Its geographic range coincides in northeastern Patagonia with the Monte Phytogeographical Province; to the South and West it is associated with coastal environments and major river valleys, respectively. In the last hundred years the populations of C. musculinus have experienced local dramatic increases, which are plausibly related to the establishment of agricultural oasis.

Mamíferos del arroyo Perucho Verna, Entre Ríos, Argentina

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En este trabajo se listan los mamíferos del arroyo Perucho Verna, provincia de Entre Ríos, Argentina. El área de estudio está localizada en el centro-este de Entre Ríos; fitogeográficamente, la región está incluida en la Provincia Pampeana, con relictos empobrecidos de la colindante Provincia del Espinal e influenciada por la Provincia
Paranaense a través de la selva en galería de los arroyos. Se llevaron a cabo ocho trabajos de campo (incluyendo trampeos, análisis de egagrópilas, transectas de observación,
evidencias indirectas, entrevistas y colección de especies vegetales). Se detectaron siete asociaciones vegetales: campo de cultivo, pastizal, arbustal, monte xerófilo, selva en
galería y selva mixta. En estas asociaciones se encontraron 33 especies de mamíferos (28 nativas y 5 exóticas) agrupadas en las familias Cricetidae (6 spp.), Didelphidae (3 spp.),
Mephitidae (1 sp.), Mustelidae (2 spp.), Molossidae (3 spp.), Vespertilionidae (2 spp.), Canidae (2 spp.), Muridae (2 spp.), Felidae (1 sp.), Dasypodidae (1 sp.), Phyllostomidae
(1 sp.), Hydrochoeridae (1 sp.), Octodontidae (1 sp.), Procyonidae (1 sp.), Caviidae (1 sp.), Chinchillidae (1 sp.), Myocastoridae (1 sp.), Leporidae (1 sp.) and Cervidae (1 sp.). Considerando que la mayor parte de la provincia de Entre Ríos se ha convertido en campos de cultivo y ganaderos, es importante remarcar el rol ocupado por los ambientes del arroyo Perucho Verna, como así también de los cientos de pequeños cauces que atraviesan la provincia, en la conservación de los ensambles de mamíferos, ya que es en estos arroyos donde aún se conservan —aunque pauperizados— muchos de los ambientes y ensambles de mamíferos originales.


Mammals of the Arroyo Perucho Verna, Entre Ríos, Argentina. The study area is located in the middle-east of Entre Ríos; fitogeographically, the region is included in the Pampean Province, with relicts of the nearest Espinal Province and influenced by the Paranaese Province through the gallery forest of the streams. Eight field works were
carried out (including trapping, owl pellet analysis, observation transects, indirect evidences, interviews and collection of vegetal species). Seven vegetal associations were
detected: crop field, pasture, shrubland, xerophilic forest, gallery forest and exotic forest. In these associations there were found 33 mammal species (28 natives and 5 exotics)
grouped in the families Cricetidae (6 spp.), Didelphidae (3 spp.), Mephitidae (1 sp.), Mustelidae (2 spp.), Molossidae (3 spp.), Vespertilionidae (2 spp.), Canidae (2 spp.), Muridae (2 spp.), Felidae (1 sp.), Dasypodidae (1 sp.), Phyllostomidae (1 sp.), Hydrochoeridae (1 sp.), Octodontidae (1 sp.), Procyonidae (1 sp.), Caviidae (1 sp.), Chinchillidae (1 sp.), Myocastoridae (1 sp.), Leporidae (1 sp.) and Cervidae (1 sp.). Considering that the major part of Entre Ríos province has became crop and livestock fields, it is important to remark the role assumed by the environments of Perucho Verna stream, and likewise the hundred of small rivers that cross the province, in the preservation of mammal assemblages, since it is in these streams where still remain—though very poor—many of the original environments and mammal assemblages.

Nuevas localidades para marsupiales patagónicos (Didelphimorphia y Microbiotheria) en el noroeste de la provincia del Chubut, Argentina

Se documentan 16 nuevas localidades para tres especies de marsupiales patagónicos en el noroeste de la provincia del Chubut. Los registros corresponden a restos esqueletarios y dentarios aislados provenientes de egagrópilas de dos especies de aves Strigiformes. Se amplía la distribución de Lestodelphys halli y Thylamys sp. hacia el oeste del Chubut y se registra la localidad más austral conocida para Dromiciops gliroides en Argentina. Los hallazgos corroboran la importancia del análisis de egagrópilas en la detección de micromamíferos poco conocidos, especialmente en áreas escasamente prospectadas.


New localities for Patagonian Marsupials (Didelphimorphia and Microbiotheria) in northwestern Chubut Province, Argentina. Sixteen new localities for three species of Patagonian marsupials in northwestern Chubut are presented. Specimens were found in owl pellets from two Strigiform species. These new localities add information to the distribution patterns of poorly known species in Patagonia. The known distribution of Lestodelphys halli and Thylamys sp. is expanded towards the west of Chubut Province; the southernmost record of Dromiciops gliroides in Argentina is presented. This work corroborates the importance of analysing owl pellets in detecting the presence of poorly known species in scarcely studied areas.