A COLOURFUL NEW SPECIES OF MYZOMELA HONEYEATER FROM ROTE ISLAND IN EASTERN INDONESIA

The avifauna of Rote Island in the Lesser Sundas is not well studied and generally considered to be similar to that of adjacent Timor Island. However, some cases of bird endemism have recently been documented on this island. A population of Myzomela honeyeater is one such example. First observed in October 1990, it has been subsumed with Myzomela dammermani from Sumba Island given its superficially similar appearance. Based on extensive morphological inspection and bioacoustic analysis, we here describe this population as a new taxon to science. Apart from previously overlooked plumage distinctions, the new taxon bioacoustically differs from M. dammermani in the presence or absence of several unique call types and considerable differences across two parameters in shared call types. Considering the importance of bioacoustics in avian species delimitation, we propose that the new Rote Myzomela be considered a distinct species. Given continued habitat conversion across its small range, we propose the International Union for Conservation of Nature and Natural Resources (IUCN) threat status Vulnerable for the species

Gene flow during glacial habitat shifts facilitates character displacement in a Neotropical flycatcher radiation

Background: Pleistocene climatic fluctuations are known to be an engine of biotic diversification at higher latitudes, but their impact on highly diverse tropical areas such as the Andes remains less well-documented. Specifically, while periods of global cooling may have led to fragmentation and differentiation at colder latitudes, they may – at the same time – have led to connectivity among insular patches of montane tropical habitat with unknown consequences on diversification. In the present study we utilized ~5.5 kb of DNA sequence data from eight nuclear loci and one mitochondrial gene alongside diagnostic morphological and bioacoustic markers to test the effects of Pleistocene climatic fluctuations on diversification in a complex of Andean tyrant-flycatchers of the genus Elaenia. Results: Population genetic and phylogenetic approaches coupled with coalescent simulations demonstrated disparate levels of gene flow between the taxon chilensis and two parapatric Elaenia taxa predominantly during the last glacial period but not thereafter, possibly on account of downward shifts of montane forest habitat linking the populations of adjacent ridges. Additionally, morphological and bioacoustic analyses revealed a distinct pattern of character displacement in coloration and vocal traits between the two sympatric taxa albiceps and pallatangae, which were characterized by a lack of gene flow. Conclusion: Our study demonstrates that global periods of cooling are likely to have facilitated gene flow among Andean montane Elaenia flycatchers that are more isolated from one another during warm interglacial periods such as the present era. We also identify a hitherto overlooked case of plumage and vocal character displacement, underpinning the complexities of gene flow patterns caused by Pleistocene climate change across the Andes. Electronic supplementary material The online version of this article (doi:10.1186/s12862-017-1047-3) contains supplementary material, which is available to authorized users

Distance sampling data in unmarked input format

Distance sampling data in unmarked input forma

Information of distance sampling point transects

Geographical coordinates, environmental covariates at each distance sampling point transcet. Geographical coordinates are using WGS84 system

Locality and sex information for the genetic samples

Geographical coordinates are using WGS84 system

SNPs used in the study

7013 SNPs from 144 individuals (missing data, linkage disequilibrium filtered)

INTEGRATIVE TAXONOMY REVEALS CRYPTIC ROBIN LINEAGE IN THE GREATER SUNDA ISLANDS

Southeast Asian avifauna is under threat from both habitat loss and illegal poaching, yet the region’s rich biodiversity remains understudied. Here, we uncover cryptic species-level diversity in the Sunda Blue Robin (Myiomela diana), a songbird complex endemic to Javan (subspecies diana) and Sumatran (subspecies sumatrana) mountains. Taxonomic inquiry into these populations has previously been hampered by a lack of DNA material and the birds’ general scarcity, especially sumatrana which is only known from few localities. We demonstrate fundamental bioacoustic differences in courtship song paired with important distinctions in plumage saturation and tail length that combine to suggest species-level treatment for the two taxa. Treated separately, both taxa are independently threatened by illegal poaching and habitat loss, and demand conservation action. Our study highlights a case of underestimated avifaunal diversity that is in urgent need of revision in the face of imminent threats to species survival.  

Bioacoustic and multi-locus DNA data of Ninox owls support high incidence of extinction and recolonisation on small, low-lying islands across Wallacea

Known for their rich biodiversity and high level of endemism, the islands of Wallacea serve as natural laboratories for the study of spatio-temporal evolution and patterns of species diversification. Our study focuses on the owl genus Ninox, particularly the Southern Boobook (N. novaeseelandiae) and Moluccan Boobook (N. squamipila) complexes, which are widely distributed across Australasia. We conducted bioacoustic and multi-locus DNA analyses of 24 Ninox owl taxa to evaluate relationships and levels of divergence within the two complexes and ultimately assess the relationship between patterns of taxonomic differentiation and bioclimatic factors. We found that taxa that are vocally and/or genetically distinct from populations on the Australian mainland are found on islands that are significantly larger and higher in altitude than taxa that are vocally and/or genetically indistinct from populations on the Australian mainland. This pattern suggests that taxa occurring on small, low-lying Wallacean islands are likely to be recent colonisers that have dispersed from Australia. Overall, our observations demonstrate that the genus Ninox is likely to have colonised the Wallacean region multiple times as small, low-lying islands undergo frequent extinction, whereas populations on large and high-altitude islands are more resilient

The conservation value of admixed phenotypes in a critically endangered species complex

In today’s environmental crisis, conservationists are increasingly confronted with terminally endangered species whose last few surviving populations may be afected by allelic introgression from closely related species. Yet there is a worrying lack of evidence-based recommendations and solutions for this emerging problem. We analyzed genome-wide DNA markers and plumage variability in a critically endangered insular songbird, the Black-winged Myna (BWM, Acridotheres melanopterus). This species is highly threatened by the illegal wildlife trade, with its wild population numbering in the low hundreds, and its continued survival urgently depending on ex-situ breeding. Its three subspecies occur along a geographic gradient of melanism and are variably interpreted as three species. However, our integrative approach revealed that melanism poorly relects the pattern of limited genomic diferentiation across BWM subspecies. We also uncovered allelic introgression into the most melanistic subspecies, tertius, from the all-black congeneric Javan Myna (A. javanicus), which is native to the same islands. Based on our results, we recommend the establishment of three separate breeding programs to maintain subspeciic traits that may confer local adaptation, but with the option of occasional cross-breeding between insurance populations in order to boost genetic diversity and increase overall viability prospects of each breeding program. Our results underscore the importance of evidence-based integrative approaches when determining appropriate conservation units. Given the rapid increase of terminally endangered organisms in need of ex-situ conservation, this study provides an important blueprint for similar programs dealing with phenotypically variable species