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1.
Mol Phylogenet Evol ; 194: 108022, 2024 May.
Artigo em Inglês | MEDLINE | ID: mdl-38325534

RESUMO

The world's largest butterfly genus Delias, commonly known as Jezebels, comprises ca. 251 species found throughout Asia, Australia, and Melanesia. Most species are endemic to islands in the Indo-Australian Archipelago or to New Guinea and nearby islands in Melanesia, and many species are restricted to montane habitats over 1200 m. We inferred an extensively sampled and well-supported molecular phylogeny of the group to better understand the spatial and temporal dimensions of its diversification. The remarkable diversity of Delias evolved in just ca. 15-16 Myr (crown age). The most recent common ancestor of a clade with most of the species dispersed out of New Guinea ca. 14 Mya, but at least six subsequently diverging lineages dispersed back to the island. Diversification was associated with frequent dispersal of lineages among the islands of the Indo-Australian Archipelago, and the divergence of sister taxa on a single landmass was rare and occurred only on the largest islands, most notably on New Guinea. We conclude that frequent inter-island dispersal during the Neogene-likely facilitated by frequent sea level change-sparked much diversification during that period. Many extant New Guinea lineages started diversifying 5 Mya, suggesting that orogeny facilitated their diversification. Our results largely agree with the most recently proposed species group classification system, and we use our large taxon sample to extend this system to all described species. Finally, we summarize recent insights to speculate how wing pattern evolution, mimicry, and sexual selection might also contribute to these butterflies' rapid speciation and diversification.


Assuntos
Borboletas , Animais , Filogenia , Borboletas/genética , Nova Guiné , Austrália , Ecossistema
2.
Pediatrics ; 143(6)2019 06.
Artigo em Inglês | MEDLINE | ID: mdl-31101703

RESUMO

BACKGROUND: Early HIV testing is needed for treatment success in young infants, but universal testing is expensive. In this study, we examined the feasibility of early infant HIV risk scores for targeted polymerase chain reaction (PCR) testing and early HIV diagnosis. METHODS: A cross-sectional cohort of newborns exposed to HIV was enrolled and PCR tested within 72 hours. We quantified associations between HIV infection and clinical and laboratory maternal-infant parameters by logistic regression models and determined sensitivity and specificity for derived risk scores. RESULTS: From August 2014 to December 2016, 1759 participants were enrolled. Mothers without antenatal care (5.7% [97 of 1688]) were more likely to deliver newborns who are PCR-positive (P = .0005). A total of 1 in 5 mothers (217 of 990; 21.9%) had HIV viral load (VL) >1000 copies per µL. A total of 432 of 1655 (26.1%) infants were preterm. Low birth weight was documented in 398 of 1598 (24.55%) and 13 of 31 (40.63%) newborns who are PCR-negative and -positive, respectively (P = .0329). A total of 204 of 1689 (12.08%) were growth restricted or small for gestational age, and 6 of 37 (16.22%) were PCR-positive. Symptomatic newborns frequently tested positive (P = .0042). The HIV PCR positivity rate was 2.2% (37 of 1703). Two-risk (combined 3-drug antiretroviral therapy [cART] duration, VL), 3-risk (cART duration, VL, symptomatic newborn), and 4-risk (cART duration, VL, symptomatic, small for gestational age newborn) models for HIV acquisition had predictive probability of 0.28, 0.498, and 0.57, respectively; this could guide targeted birth testing. However, using the 3- and 4-risk scores (probability 0.02 and 0.04), 20% and 24% will be missed compared with universal testing. CONCLUSIONS: Targeted newborn testing requires access to maternal VL. Even if risk models include parameters such as maternal cART history, birth weight, weeks' gestation, and symptoms, 1 in 5 newborns who are infected will not be targeted. At present, we support universal PCR testing at birth within the South African prevention of mother-to-child transmission of HIV context.


Assuntos
Infecções por HIV/diagnóstico , Infecções por HIV/genética , Transmissão Vertical de Doenças Infecciosas , Triagem Neonatal/métodos , Complicações Infecciosas na Gravidez/diagnóstico , Complicações Infecciosas na Gravidez/genética , Adulto , Estudos de Coortes , Estudos Transversais , Diagnóstico Precoce , Feminino , Infecções por HIV/epidemiologia , Humanos , Recém-Nascido , Gravidez , Complicações Infecciosas na Gravidez/epidemiologia , Reação em Cadeia da Polimerase em Tempo Real/métodos , Fatores de Risco , África do Sul/epidemiologia , Carga Viral/genética , Carga Viral/métodos
3.
Zookeys ; (774): 1-15, 2018.
Artigo em Inglês | MEDLINE | ID: mdl-30034260

RESUMO

The most distinctive species of Polyura, P. inopinatus, described from a single specimen said to be from North Sulawesi, Indonesia, has been a great mystery since it was first described by Röber, in 1940. The holotype, originally illustrated in monochrome in the journal Deutsche Entomologische Zeitschrift, Iris, was lost very soon after it was described, almost certainly destroyed during allied bombing of Dresden in the 1940s. No other specimen was known for almost eight decades. We suggest that the type locality (Sulawesi) is incorrect and that the holotype was more likely to have been collected in the Baining Mountains, East New Britain Province, Papua New Guinea. We report the recent discovery of several male P. inopinatus from West New Britain Province, and describe and illustrate specimens. A neotype is designated.

4.
Mol Phylogenet Evol ; 123: 50-58, 2018 06.
Artigo em Inglês | MEDLINE | ID: mdl-29428509

RESUMO

Hypolimnas butterflies (Nymphalidae), commonly known as eggflies, are a popular model system for studying a wide range of ecological questions including mimicry, polymorphism, wing pattern evolution, and Wolbachia-host interactions. The lack of a time-calibrated phylogeny for this group has precluded understanding its evolutionary history. We reconstruct a species-level phylogeny using a nine gene dataset and estimate species divergence times. Based on the resulting tree, we investigate the taxon's historical biogeography, examine the evolution of host plant preferences, and test the hypothesis that the endosymbiotic bacterium Wolbachia mediates gene transfer between species. Our analyses indicate that the species are grouped within three strongly supported, deeply divergent clades. However, relationships among these three clades are uncertain. In addition, many Hypolimnas species are not monophyletic or monophyletic with weak support, suggesting widespread incomplete lineage sorting and/or introgression. Biogeographic analysis strongly indicates that the genus diverged from its ancestor in Africa and subsequently dispersed to Asia; the strength of this result is not affected by topological uncertainties. While the larvae of African species feed almost exclusively on Urticaceae, larvae of species found further east often feed on several additional families. Interestingly, we found an identical mitochondrial haplotype in two Hypolimnas species, H. bolina and H. alimena, and a strong association between this mitotype and the Wolbachia strain wBol1a. Future investigations should explore the plausibility of Wolbachia-mediated introgression between species.


Assuntos
Evolução Biológica , Borboletas/genética , Borboletas/microbiologia , Wolbachia/fisiologia , África , Animais , Sequência de Bases , Teorema de Bayes , Biodiversidade , DNA Mitocondrial/genética , Haplótipos/genética , Larva/fisiologia , Funções Verossimilhança , Mitocôndrias/genética , Filogenia , Filogeografia , Análise de Sequência de DNA
5.
Zookeys ; (571): 113-31, 2016.
Artigo em Inglês | MEDLINE | ID: mdl-27110161

RESUMO

Jamides vasilia sp. n., from montane West New Britain Province, Papua New Guinea, is described and illustrated. The new species is strongly divergent from other known Jamides Hübner, 1819 in possessing a high antenna-forewing length ratio, long androconia on the hindwing upperside and a strongly convex forewing inner margin in the male. It is compared by external structures, male genitalia and mtDNA sequence data to putative related species in the cyta group of Jamides. Notes on various Jamides taxa from the Bismarck Archipelago are also provided, with Jamides pseudosias (Rothschild, 1915) and Jamides reverdini (Fruhstorfer, 1915) recorded from New Britain for the first time.

6.
Mol Phylogenet Evol ; 91: 194-209, 2015 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-26021440

RESUMO

The charismatic tropical Polyura Nawab butterflies are distributed across twelve biodiversity hotspots in the Indomalayan/Australasian archipelago. In this study, we tested an array of species delimitation methods and compared the results to existing morphology-based taxonomy. We sequenced two mitochondrial and two nuclear gene fragments to reconstruct phylogenetic relationships within Polyura using both Bayesian inference and maximum likelihood. Based on this phylogenetic framework, we used the recently introduced bGMYC, BPP and PTP methods to investigate species boundaries. Based on our results, we describe two new species Polyura paulettae Toussaint sp. n. and Polyura smilesi Toussaint sp. n., propose one synonym, and five populations are raised to species status. Most of the newly recognized species are single-island endemics likely resulting from the recent highly complex geological history of the Indomalayan-Australasian archipelago. Surprisingly, we also find two newly recognized species in the Indomalayan region where additional biotic or abiotic factors have fostered speciation. Species delimitation methods were largely congruent and succeeded to cross-validate most extant morphological species. PTP and BPP seem to yield more consistent and robust estimations of species boundaries with respect to morphological characters while bGMYC delivered contrasting results depending on the different gene trees considered. Our findings demonstrate the efficiency of comparative approaches using molecular species delimitation methods on empirical data. They also pave the way for the investigation of less well-known groups to unveil patterns of species richness and catalogue Earth's concealed, therefore unappreciated diversity.


Assuntos
Borboletas/classificação , Animais , Teorema de Bayes , Biodiversidade , Borboletas/anatomia & histologia , Borboletas/genética , Filogenia , Análise de Sequência de DNA
7.
Zootaxa ; 3926(1): 147-50, 2015 Mar 04.
Artigo em Inglês | MEDLINE | ID: mdl-25781776

RESUMO

For 30 years the highly distinctive Schneider's Surprise butterfly, Tiradelphe schneideri Ackery & Vane-Wright, 1984, has been known only from the two original type specimens, both female. Here we describe and illustrate the previously unknown male of this Guadalcanal endemic member of the Danaina-the subtribe of Nymphalidae: Danainae to which Tiradelphe has always been assigned. Unexpectedly, male T. schneideri completely lack alar androconia, and are thus  unlike all other species of Danaina and its sister group, the Amaurina. The new information will permit a reassessment of the phylogenetic relationships of Tiradelphe. This enigmatic genus may well be more isolated than previously supposed, with implications not only for our understanding of pheromone communication in these insects, but also the evolution and biogeography of the tribe Danaini in the Indo-Pacific.


Assuntos
Borboletas/classificação , Estruturas Animais/anatomia & histologia , Estruturas Animais/crescimento & desenvolvimento , Animais , Evolução Biológica , Tamanho Corporal , Borboletas/anatomia & histologia , Borboletas/crescimento & desenvolvimento , Ecossistema , Feminino , Masculino , Tamanho do Órgão , Especificidade da Espécie
8.
Zookeys ; (395): 33-55, 2014.
Artigo em Inglês | MEDLINE | ID: mdl-24715788

RESUMO

Six new species of the large lycaenid genus Philiris Röber, 1891 (Philiris petriei sp. n., Philiris bubalisatina sp. n., Philiris baiteta sp. n., Philiris radicala sp. n., Philiris hindenburgensis sp. n. and Philiris parsonsi sp. n.), from Papua New Guinea, are described and illustrated, as are the early stages of the former taxon, with Litsea sp. near callophyllantha K. Schum (Lauraceae) recorded as the larval food plant. The holotypes of all but the latter are deposited in the ANIC, with that of P. parsonsi located in the BMNH. The external facies and male genitalia of all new species are compared in detail to putative known related species, and the types of these, in nearly all cases, are also illustrated.

9.
BMC Evol Biol ; 10: 172, 2010 Jun 10.
Artigo em Inglês | MEDLINE | ID: mdl-20537168

RESUMO

BACKGROUND: Butterflies of the subtribe Mycalesina (Nymphalidae: Satyrinae) are important model organisms in ecology and evolution. This group has radiated spectacularly in the Old World tropics and presents an exciting opportunity to better understand processes of invertebrate rapid radiations. However, the generic-level taxonomy of the subtribe has been in a constant state of flux, and relationships among genera are unknown. There are six currently recognized genera in the group. Mycalesis, Lohora and Nirvanopsis are found in the Oriental region, the first of which is the most speciose genus among mycalesines, and extends into the Australasian region. Hallelesis and Bicyclus are found in mainland Africa, while Heteropsis is primarily Madagascan, with a few species in Africa. We infer the phylogeny of the group with data from three genes (total of 3139 bp) and use these data to reconstruct events in the biogeographic history of the group. RESULTS: The results indicate that the group Mycalesina radiated rapidly around the Oligocene-Miocene boundary. Basal relationships are unresolved, but we recover six well-supported clades. Some species of Mycalesis are nested within a primarily Madagascan clade of Heteropsis, while Nirvanopsis is nested within Lohora. The phylogeny suggests that the group had its origin either in Asia or Africa, and diversified through dispersals between the two regions, during the late Oligocene and early Miocene. The current dataset tentatively suggests that the Madagascan fauna comprises two independent radiations. The Australasian radiation shares a common ancestor derived from Asia. We discuss factors that are likely to have played a key role in the diversification of the group. CONCLUSIONS: We propose a significantly revised classification scheme for Mycalesina. We conclude that the group originated and radiated from an ancestor that was found either in Asia or Africa, with dispersals between the two regions and to Australasia. Our phylogeny paves the way for further comparative studies on this group that will help us understand the processes underlying diversification in rapid radiations of invertebrates.


Assuntos
Borboletas/classificação , Evolução Molecular , Especiação Genética , Filogenia , África , Animais , Australásia , Teorema de Bayes , Borboletas/genética , Genes de Insetos , Geografia , Funções Verossimilhança , Madagáscar , Análise de Sequência de DNA
10.
Mol Phylogenet Evol ; 54(2): 386-94, 2010 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-19686856

RESUMO

We report a rapid radiation of a group of butterflies within the family Nymphalidae and examine some aspects of popular analytical methods in dealing with rapid radiations. We attempted to infer the phylogeny of butterflies belonging to the subtribe Coenonymphina sensu lato using five genes (4398bp) with Maximum Parsimony, Maximum Likelihood and Bayesian analyses. Initial analyses suggested that the group has undergone rapid speciation within Australasia. We further analyzed the dataset with different outgroup combinations the choice of which had a profound effect on relationships within the ingroup. Modelling methods recovered Coenonymphina as a monophyletic group to the exclusion of Zipaetis and Orsotriaena, irrespective of outgroup combination. Maximum Parsimony occasionally returned a polyphyletic Coenonymphina, with Argyronympha grouping with outgroups, but this was strongly dependent on the outgroups used. We analyzed the ingroup without any outgroups and found that the relationships inferred among taxa were different from those inferred when either of the outgroup combinations was used, and this was true for all methods. We also tested whether a hard polytomy is a better hypothesis to explain our dataset, but could not find conclusive evidence. We therefore conclude that the major lineages within Coenonymphina form a near-hard polytomy with regard to each other. The study highlights the importance of testing different outgroups rather than using results from a single outgroup combination of a few taxa, particularly in difficult cases where basal nodes appear to receive low support. We provide a revised classification of Coenonymphina; Zipaetis and Orsotriaena are transferred to the tribe Eritina.


Assuntos
Borboletas/genética , Evolução Molecular , Especiação Genética , Filogenia , Animais , Australásia , Teorema de Bayes , Borboletas/classificação , Genes de Insetos , Funções Verossimilhança , Modelos Genéticos , Análise de Sequência de DNA
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