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Abstract: The subfamily Cynopterinae comprises ca. 24 species of pteropodid bats (Family Pteropodidae) distributed exclusively in South and Southeast Asia. Although some studies have supported monophyly of the subfamily, molecular analyses have produced contradictory results and there has been little agreement on relationships of cynopterines to other megabat groups. However, no previous studies have included a complete sampling of cynopterine genera. Here we describe a phylogenetic analysis of Cynopterinae based on more than 6000bp from six different genes sampled in representatives of all 14 recognized genera. Our results support the monophyly of Cynopterinae but refute a close relationship of cynopterines with Nyctimeninae. Within Cynopterinae, our analyses consistently recovered two monophyletic clades, which we recommend be recognized formally as tribes: Cynopterini and Balionycterini. Biogeographic analyses indicate a Sundaland origin of the Cynopterinae and divergence date estimates suggest different timing of diversification of the two major cynopterine clades. [Copyright &y& Elsevier]

Abstract: Suprafamilial relationships among characiform fishes and implications for the taxonomy and biogeographic history of the Characiformes were investigated by parsimony analysis of four nuclear and two mitochondrial genes across 124 ingroup and 11 outgroup taxa. Simultaneous analysis of 3660 aligned base pairs from the mitochondrial 16S and cytochrome b genes and the nuclear recombination activating gene (RAG2), seven in absentia (sia), forkhead (fkh), and α-tropomyosin (trop) gene loci confirmed the non-monophyly of the African and Neotropical assemblages and corroborated many suprafamilial groups proposed previously on the basis of morphological features. The African distichodontids plus citharinids were strongly supported as a monophyletic Citharinoidei that is the sistergroup to all other characiforms, which form a monophyletic Characoidei composed of two large clades. The first represents an assemblage of both African and Neotropical taxa, wherein a monophyletic African Alestidae is sister to a smaller clade comprised of the Neotropical families Ctenolucidae, Lebiasinidae, and the African Hepsetidae, with that assemblage sister to a strictly Neotropical clade comprised of the Crenuchidae and Erythrinidae. The second clade within the Characoidei is strictly Neotropical and includes all other Characiformes grouped into two well supported major clades. The first, corresponding to a traditional definition of the Characidae, is congruent with some groupings previously supported by morphological evidence. The second clade comprises a monophyletic Anostomoidea that is sister to a clade formed by the families Hemiodontidae, Parodontidae, and Serrasalmidae, with that assemblage, in turn, the sistergroup of the Cynodontidae. Serrasalmidae, traditionally regarded as a subfamily of Characidae, was recovered as the sistergroup of (Anostomoidea (Parodontidae+Hemiodontidae)) and the family Cynodontidae was recovered with strong support as the sistergroup to this assemblage. Our results reveal three instances of trans-continental sistergroup relationships and, in light of the fossil evidence, suggest that marine dispersal cannot be ruled out a priori and that a simple model of vicariance does not readily explain the biogeographic history of the characiform fishes. [Copyright &y& Elsevier]

Abstract: We present a revised molecular phylogeny of the Drosophila repleta group including 62 repleta group taxa and nine outgroup species based on four mitochondrial and six nuclear DNA sequence fragments. With ca. 100 species endemic to the New World, the repleta species group represents one of the major species radiations in the genus Drosophila. Most repleta group species are associated with cacti in arid or semiarid regions. Contrary to previous results, maximum likelihood and Bayesian phylogenies of the 10-gene dataset strongly support the monophyly of the repleta group. Several previously described subdivisions in the group were also recovered, despite poorly resolved relationships between these clades. Divergence time estimates suggested that the repleta group split from its sister group about 21millionyears ago (Mya), although diversification of the crown group began ca. 16Mya. Character mapping of patterns of host plant use showed that flat leaf Opuntia use is common throughout the phylogeny and that shifts in host use from Opuntia to the more chemically complex columnar cacti occurred several times independently during the history of this group. Although some species retained the use of Opuntia after acquiring the use of columnar cacti, there were multiple, phylogenetically independent instances of columnar cactus specialization with loss of Opuntia as a host. Concordant with our proposed timing of host use shifts, these dates are consistent with the suggested times when the Opuntioideae originated in South America. We discuss the generally accepted South American origin of the repleta group. [Copyright &y& Elsevier]

Abstract: The Hawaiian Drosophila offer a unique opportunity to examine evolutionary questions because of the known ages of the Hawaiian Islands and the large number of species endemic to this archipelago. One of the more well studied groups of Hawaiian Drosophila is the planitibia species group, a long-standing population genetic model system. Here we present a molecular phylogenetic hypothesis of all 17 taxa in the planitibia group based on nucleotide sequences from two mitochondrial (16S and COII) and four nuclear (Adh, Gpdh, Yp1, and Yp2) loci, accounting for over 4kb of sequence per taxon. We use these data to estimate major divergence times within this group. Our results suggest that the basal diversification within this group, calculated at 6.1±0.47 MY, predates the oldest high island of Kauai. The older diversifications in this group took place on Kauai, with subsequent colonization and speciation events occurring as new islands became available to Drosophila. Understanding of the phylogenetic relationships of this important group will place the existing population genetic work in a macroevolutionary context and stimulate additional work, particularly on those taxa endemic to the Maui Nui complex of islands. [Copyright &y& Elsevier]