The substantial body of research on Holarctic ground squirrels amassed over the past century documents considerable variability in morphological, cytogenetic, ecological, and behavioral attributes in the genus Spermophilus F. Cuvier, 1825. Recent molecular phylogenetic studies suggest that the traditionally recognized genera Marmota Blumenbach, 1779 (marmots), Cynomys Rafinesque, 1817 (prairie dogs), and Ammospermophilus Merriam, 1892 (antelope ground squirrels) render Spermophilus paraphyletic, potentially suggesting that multiple generic-level lineages should be credited within Spermophilus. Herein, we recognize 8 genera formerly subsumed in Spermophilus, each of which is morphologically diagnosable, craniometrically distinctive, and recovered as a monophyletic clade in phylogenetic analyses utilizing the mitochondrial gene cytochrome b. Generic-level names are available for each of these ground squirrel assemblages, most of which are exclusively or predominantly North American in distribution (Notocitellus A.

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Comparative population genetics of ecological guilds can reveal generalities in patterns of differentiation bearing on hypotheses regarding the origin and maintenance of community diversity. Contradictory estimates of host specificity and beta diversity in tropical Lepidoptera (moths and butterflies) from New Guinea and the Americas have sparked debate on the role of host-associated divergence and geographic isolation in explaining latitudinal diversity gradients. We sampled haplotypes of mitochondrial cytochrome c oxidase I from 28 Lepidoptera species and 1,359 individuals across four host plant genera and eight sites in New Guinea to estimate population divergence in relation to host specificity and geography. Analyses of molecular variance and haplotype networks indicate varying patterns of genetic structure among ecologically similar sympatric species. One-quarter lacked evidence of isolation by distance or host-associated differentiation, whereas 21% exhibited both. Fourteen percent of the species exhibited host-associated differentiation without geographic isolation, 18% showed the opposite, and 21% were equivocal, insofar as analyses of molecular variance and haplotype networks yielded incongruent patterns. Variation in dietary breadth among community members suggests that speciation by specialization is an important, but not universal, mechanism for diversification of tropical Lepidoptera. Geographically widespread haplotypes challenge predictions of vicariance biogeography. Dispersal is important, and Lepidoptera communities appear to be highly dynamic according to the various phylogeographic histories of component species. Population genetic comparisons among herbivores of major tropical and temperate regions are needed to test predictions of ecological theory and evaluate global patterns of biodiversity. community ecology | DNA barcoding | phylogeography | plant-insect interactions | speciation

We present the first comprehensive taxonomic revision and review the biology of the olingos, the endemic Neotropical procyonid genus Bassaricyon, based on most specimens available in museums, and with data derived from anatomy, morphometrics, mitochondrial and nuclear DNA, field observations, and geographic range modeling. Species of Bassaricyon are primarily forest-living, arboreal, nocturnal, frugivorous, and solitary, and have one young at a time. We demonstrate that four olingo species can be recognized, including a Central American species (Bassaricyon gabbii), lowland species with eastern, cis-Andean (Bassaricyon alleni) and western, trans-Andean (Bassaricyon medius) distributions, and a species endemic to cloud forests in the Andes. The oldest evolutionary divergence in the genus is between this last species, endemic to the Andes of Colombia and Ecuador, and all other species, which occur in lower elevation habitats. Surprisingly, this Andean endemic species, which we call the Olinguito, has never been previously described; it represents a new species in the order Carnivora and is the smallest living member of the family Procyonidae. We report on the biology of this new species based on information from museum specimens, niche modeling, and fieldwork in western Ecuador, and describe four Olinguito subspecies based on morphological distinctions across different regions of the Northern Andes.

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Two new species of flying foxes (genus Pteropus) from the Samoan archipelago are described on the basis of modern museum specimens collected in the mid-19th century. A medium-sized species (P. allenorum, n. sp.) is introduced from the island of Upolu (Independent Samoa), based on a specimen collected in 1856 and deposited in the Academy of Natural Sciences of Philadelphia. It has not been collected again, and we regard it as almost certainly extinct. This species is smaller bodied and has much smaller teeth than both extant congeners recorded in the contemporary fauna of Samoa (Pteropus samoensis and P. tonganus). The closest relative of this new species may be Pteropus fundatus of northern Vanuatu. The disjunct historical distribution of these two smalltoothed flying foxes (in Vanuatu and Samoa) suggests that similar species may have been more extensively distributed in the remote Pacific in the recent past. Another species, a very large flying fox with large teeth (P. coxi, n. sp.), is described from two skulls collected in Samoa in 1839-1841 during the U.S. Exploring Expedition; it too has not been collected since. This robust species resembles Pteropus samoensis and Pteropus anetianus of Vanuatu in craniodental conformation but is larger than other Polynesian Pteropus, and in some features it is ecomorphologically convergent on the Pacific monkey-faced bats (the pteropodid genera Pteralopex and Mirimiri). On the basis of eyewitness reports from the early 1980s, it is possible that this species survived until recent decades, or is still extant. These two new Samoan species join Pteropus tokudae of Guam, P. pilosus of Palau, P. subniger of the Mascarenes, and P. brunneus of coastal north-eastern Australia as flying

Common raven (Corvus corax) populations in Mojave Desert regions of southern California and Nevada have increased dramatically over the past five decades. This growth has been attributed to increased human development in the region, as ravens have a commensal relationship with humans and feed extensively at landfills and on road-killed wildlife. Ravens, as a partially subsidized predator, also represent a problem for native desert wildlife, in particular threatened desert tortoises (Gopherus agassizii). However, it is unclear whether the more than 15-fold population increase is due to in situ population growth or to immigration from adjacent regions where ravens have been historically common.