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Brand L.,Loma Linda University | Urbina M.,Museo de Historia Natural | Chadwick A.,Southwestern Adventist University | DeVries T.J.,University of Washington | Esperante R.,Geoscience Research Institute
Journal of South American Earth Sciences

The Miocene/Pliocene Pisco Formation of Peru contains a rich marine vertebrate fossil record, providing a unique opportunity for the study of paleoecology and evolution, along with the sedimentological context of the fossils. The lack of a high-resolution stratigraphic framework has hampered such study. In this paper we develop the needed stratigraphy for the areas in the Pisco Formation where most of the vertebrate paleontological research is occurring. In the Ica Valley and in the vicinity of Lomas, series of lithologically or paleontologically unique marker beds were identified. These were walked out and documented with GPS technology. Measured sections connecting these marker beds provide a stratigraphic framework for the areas studied. GPS locations, maps of the marker beds on aerial photographs, and outcrop photographs allow field determination of the stratigraphic positions of study areas. © 2011 Elsevier Ltd. Source

Acosta-Hospitaleche C.,Museo de La Plata | Altamirano-Sierra A.,Museo de Historia Natural | Stucchi M.,Asociacion Para la Investigacion y Conservacion de la Biodiversidad AICB
Revista Mexicana de Ciencias Geologicas

The morphological variation presents in the penguin tarsometatarsi from Pisco Formation (Miocene-Pliocene) from Peru assigned to Spheniscus Brisson, 1760 is analyzed. Metrics and geometric techniques to quantify the diversity present in each of the nine sites localities at the south-central coast were applied. A comparative description of Spheniscus and its Miocene morphologically closest genus Palaeospheniscus Moreno and Mercerat, 1891 is also provided. They together constitute the penguin avifauna of the Miocene of Peru. The results allow us to recognize that the intra-specific diversity is at the same level of variation than the inter-specific one. At least five species of Spheniscus are hereby recognized: Spheniscus urbinai Stucchi 2002, S. megaramphus Stucchi, Urbina and Giraldo 2003, S.muizoni Göhlich 2007 and two innominated species. Each one of these species transgresses the boundaries between the localities, being represented in more than one locality. It was not possible to distinguish S. chilensis Emslie and Guerra Correa, 2003 from its tarsometatarso. The presence of six species in this unit could be related to the establishment of cold water and the advent of favorable conditions for diversification. Source

Piacentini L.N.,Museo Argentino de Ciencias Naturales Bernardino Rivadavia | Ramirez M.J.,Museo Argentino de Ciencias Naturales Bernardino Rivadavia | Silva D.,Museo de Historia Natural
Invertebrate Systematics

A new genus of the spider family Zoropsidae, Cauquenia, gen. nov., is proposed for Cauquenia maule, sp. nov., from the Maule region in central Chile. The familial placement is tested through the inclusion of Cauquenia in the latest major published morphological analyses of the superfamily Lycosoidea, and the subfamily placement of the South American zoropsid genus Itatiaya Mello-Leitão is also tested including them in the Raven and Stumkat (2005) analysis. Cauquenia and Itatiaya are closely related to the African genera Griswoldia Dippenaar-Schoeman & Jocqué and Phanotea Simon, with which it shares a cup-shaped median apophysis on the male pedipalp and tooth-like projections on the lateral lobes of the epigyne in females. The patterns of evolution of the cribellum and the male tibial crack in Lycosoidea are explored; the cribellum shows up as primitively present, with three losses and four independent acquisitions, and the male tibial crack is lost twice. An asymmetric cost in cribellum gain:loss of 6:1 produces a primitive cribellum with 12 losses. © 2013 CSIRO. Source

Phylogenetic relationships of Orthalicoidea, a highly diverse and dominant element in the Neotropics, were studied using nuclear and mitochondrial DNA sequences (ITS2/28S, CO1, H3). Specimens of various locations from the Southern Hemisphere (South America, Africa, Australia, New Zealand, Solomon Islands) were analysed (74 taxa, representing 30 genera). Our results support previously presented hypotheses, but also give surprises in terms of unexpected topologies. Phylogenetic trees were estimated using maximum likelihood and Bayesian inference, and compared with traditional classifications. Phylogenetic estimations using three loci gave a strong support for monophyly of Orthalicoidea, as well as for some clades within this group (Bulimulidae, Bothriembryontidae, Orthalicidae, Amphibulimulidae), but not for others (Odontostomidae and Megaspiridae). In the resulting revision of the classification scheme of the Orthalicoidea, the tribe Simpulopsini is raised to family rank. One new subfamily is recognized, the Bostrycinae. The family Bulimulidae Tryon 1867 is retained under ICZN Art. 35.5, despite the senior synonymy of Peltellinae Gray 1855. Our analysis supports an origin of the Orthalicoidea in South America, with subsequent radiations into other parts of the Neotropics and the Southern Hemisphere. The hypothesis that the distribution on the southern continents may be explained by vicariance due to break-up of Gondwana is only partially supported by divergence time analysis using fossil calibrations. Ancestral area reconstruction suggests various independent dispersals out of South America into Central America and the West Indies, and possibly two independent dispersals to explain the remaining relations between groups of taxa on the southern continents. Divergence time analysis further shows that the major diversification of extant taxa within the superfamily may have started around the Cretaceous-Paleogene boundary. © E. Schweizerbart'sche Verlagsbuchhandlung (Nägele u. Obermiller), 2012. Source

Alvarado M.,University of Kansas | Figueroa L.,Museo de Historia Natural
Revista Peruana de Biologia

Four species of the parasitoid wasp genus Anomalon Panzer are recorded for the first time in Peru - Anomalon cotoi Gauld & Bradshaw, 1997, Anomalon duniae Gauld & Bradshaw, 1997, Anomalon fuscipes (Cameron, 1886), and Anomalon sinuatum (Morley, 1912). © Los autores. Source

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