So-called 'kentriodontids' are extinct dolphin-like odontocetes known from the Early to Late Miocene worldwide. Although recent studies have proposed that they were monophyletic, their taxonomic ...relationships still remain controversial. Such a controversy exists partly because of the predominance of primitive morphologies in this taxon, but the fact is that quite a few 'kentriodontids' are known only from fragmentary skulls and/or isolated periotics. A new 'kentriodontid' Platysvercus ugonis gen. et sp. nov. is described based on a nearly complete skull from the upper Lower Miocene Sugota Formation, Akita Prefecture, northern Japan. Based on the phylogenetic analysis of P. ugonis described here, the monophyly of the 'kentriodontids' is confirmed, and it is recognized as the superfamily Kentriodontoidea. This new superfamily is subdivided into two families as new ranks: Kentriodontidae and Lophocetidae. Based on the paleobiogeographic analysis of the Kentriodontoidea, their common ancestor emerged in the North Pacific Ocean and spread over the Northern Hemisphere. Initial diversification of the Kentriodontidae in the North Pacific Ocean and the Lophocetidae in the North Atlantic Ocean was recognized as a vicariance event. The diversification and extinction of the Kentriodontoidea could have been synchronously influenced by climate events during the Middle Miocene.
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DOBA, IZUM, KILJ, NUK, PILJ, PNG, SAZU, SIK, UILJ, UKNU, UL, UM, UPUK
The Neotropical avian genus Thraupis (Passeriformes, Thraupidae) currently comprises seven species that are widespread and abundant throughout their ranges. However, no phylogenetic hypothesis with ...comprehensive intraspecific sampling is available for the group and, therefore, currently accepted species limits remain untested. We obtained sequence data for two mitochondrial (ND2, cyt-b) and three non-coding nuclear (TGFB2, MUSK, and betaF5) markers from 118 vouchered museum specimens. We conducted population structure and coalescent-based species-tree analyses using a molecular clock calibration. We integrated these results with morphometric and coloration analyses of 1,003 museum specimens to assess species limits within Thraupis. Our results confirm that Thraupis is a monophyletic group and support its origin in the late Miocene and subsequent diversification during the Pleistocene. However, we found conflicts with previous phylogenies. We recovered Thraupis glaucocolpa to be sister to all other species in the genus, and T. cyanoptera to the remaining five species. Our phylogenetic trees and population structure analyses uncovered phylogeographic structure within Thraupis episcopus that is congruent with geographic patterns of phenotypic variation and distributions of some named taxa. The first genetic and phenotypic cluster in T. episcopus occurs east of the Andes and is diagnosed by the white patch on the lesser and median wing coverts, whereas the second group has a blue patch on the wing and distributes to the west of Colombia's eastern Andes. Finally, we present evidence of hybridization and ongoing gene flow between several taxa at different taxonomic levels and discuss its taxonomic implications.
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DOBA, IZUM, KILJ, NUK, PILJ, PNG, SAZU, SIK, UILJ, UKNU, UL, UM, UPUK
To solve the taxonomic affiliation of Bulbophyllum physometrum, the only known species of the Bulbophyllym sect. Physometra (Orchidaceae, Epidendroideae), we conducted phylogenetic analyses based on ...nuclear markers, i.e., ITS and the low-copy gene Xdh, and the plastid region matK. We used Asian Bulbophyllum taxa, with a special focus on species from the sections Lemniscata and Blepharistes, i.e., the only Asian sections of this genus with bifoliate pseudobulbs, as in B. physometrum. Unexpectedly, the results of molecular phylogenetic analyses showed that B. physometrum is most probably more related to the representatives of the sections Hirtula and Sestochilos than Blepharistes or Lemniscata.
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IZUM, KILJ, NUK, PILJ, PNG, SAZU, UL, UM, UPUK
Human T-lymphotropic virus 1 (HTLV-1) was discovered in 1980 as the first human retrovirus. As zoonosis, HTLV-1 derives from jumps to humans from simian T-lymphotropic virus naturally infecting ...monkeys in Central and Western Sub-Saharan Africa for thousands of years. Molecular clock study estimates an ancestor for all human HTLV-1s around 30,000-40,000 years ago. As expected, Africa accounts for the largest number of HTLV-1 infections worldwide. However, Latin America is the second region endemic for HTLV-1 globally. As shown in figure 1, four areas of high HTLV-1 prevalence can be recognized, namely, at the Caribbean basin, Brazil, Peru, and along the Andes mountains. Phylogenetic studies have examined viral sequences from isolates in all these regions, including the exam of older mummies. Based on these data, a reconstruction of the earliest introduction and dissemination of HTLV-1 in America can be postulated.
For several years, there have been continuous reports of black flies in Mississippi with evidence of transmission of Leucocytozoon spp. This study was conducted to determine the presence and ...diversity of Leucocytozoon spp. in black flies captured throughout Mississippi. Thirty-three collections, consisting of 346 specimens, were made during the 2-yr period (2015-2016) at 10 locations around the state. In addition to these systematic biweekly collections, 46 specimens were taken in 10 collections at four additional sites from 2009 to 2014, as well as 388 specimens taken in 14 collections during a severe black fly outbreak during March and April of 2018. Out of 186 pooled samples, 21 samples were positive for haemosporidian DNA. Eighteen of those samples were identified as Leucocytozoon spp. A phylogenetic tree was constructed using the novel sequences along with existing sequences from the MalAvi database. Results showed several of the sequences constructed in this study had high divergence from the existing sequences from the database. Key words: black flies, Leucocytozoon, Simuliidae, leucocytozoonosis, Simulium
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