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We describe three new species of forest robin in the genus Stiphrornis; two from West Africa and one from the Congo Basin. Each species represents a distinct phylogenetic lineage based on genetic analysis. In addition to genetic differentiation, each new species is diagnosable from other Stiphrornis lineages by morphology, and by plumage. One of the new species appears to be restricted to the Central and Brong-Ahafo Regions of Ghana, and another is restricted to Benin and the Central Region of Ghana. In Ghana, these two new species presumably come into contact with Stiphrornis erythrothorax (Western Region of Ghana and westward), and there is evidence that one of the new species has a distinguishably different song from erythrothorax. The distribution of the third new species is primarily on the south bank of the Congo River, near the city of Kisangani. Recognition of these species provides additional evidence that Afrotropical forests are harbouring substantial cryptic diversity, and that our knowledge o...

Sillem's Mountain Finch Leucosticte sillemi was described in 1992 on the basis of an adult and an immature specimen collected in western Tibet in September 1929, but its taxonomic validity and phyl ...

The conservation of endangered taxa often critically depends on accurate taxonomic designations. The status of the Gran Canaria population of the Blue Chaffinch Fringilla t. polatzeki has not been reevaluated since the early 1900s when this taxon was described as a subspecies and combined with the much more common Tenerife Blue Chaffinch F. t. teydea in a single species. We show that multiple diagnostic differences in plumage, songs, calls and morphometrics distinguish F. t. polatzeki from F. t. teydea. Preliminary playback experiments suggest that F. t. polatzeki is able to discriminate between songs of both taxa. Along with previously reported differences in mitochondrial DNA, these findings show that the blue chaffinches on Gran Canaria and Tenerife represent two highly distinctive species: F. polatzeki and F. teydea. Gran Canaria Blue Chaffinch is Europe’s rarest passerine species and should be classified as Critically Endangered. Its long-term survival in the wild currently depends on a very small (

The Lesser White-fronted Goose [Anser erythropus (Linnaeus, 1758)] is one of the most threatened Palearctic goose species, with the Fennoscandinavian subpopulation in particular having seen a drastic decline over the last century. In the 1990s, captive-bred Lesser White-fronted Geese were used successfully for reintroduction and restocking in Sweden and Finland. The discovery of Greater White-fronted Goose [Anser albifrons (Scopoli, 1769)] mtDNA haplotypes in some of these captive-bred birds ( Ruokonen et al. 2000 ) suggested that hybridisation had occurred during captive propagation and led to the discontinuation of the release of captive goslings. Here we report two hybrids of Lesser×Greater White-fronted Geese that were collected on their wintering grounds in England in 1936 and Holland in 1966. Birds from western Russia normally do not migrate south to Western Europe. Hence, these birds most likely originated from the Fennoscandinavian subpopulation and were collected prior to the commencement of the captive-breeding programmes. Both specimens show a heterogeneous set of morphological characters, some of which shared with the putative parent species and others being intermediate between the two White-fronted Goose species. A Canonical Discriminant Function analysis positions both specimens between the two putative parent species, making their hybrid status likely. We show, thus, that hybridisation between Greater and Lesser White-fronted Geese does occur naturally, albeit perhaps infrequently, and argue that the presence of Greater White-fronted Goose mtDNA haplotypes in Lesser White-fronted Goose may be the result of this naturally occurring hybridisation. Our data provide additional information on the debate whether the restocking programmes were halted for the right reasons and whether it is desirable to re-commence with the reintroduction programme.

This is the third update on the taxonomy of species and higher taxa on the Dutch List since Voous (1977). It summarizes decisions made by the Commissie Systematiek Nederlandse Avifauna (CSNA) between Jan 2004 and Dec 2008. Changes in this report fall into five categories: (1) the sequence within and among some groups is changed to reflect their phylogenetic relationships (flamingos and grebes, eagles, shanks, gulls, terns, swallows and tits); (2) 20 scientific names are changed due to generic revisions (Aquila pennata, A. fasciata, Chroicocephalus genei, C. philadelphia, C. ridibundus, Hydrocoloeus minutus, Onychoprion anaethetus, Sternula albifrons, Hydroprogne caspia, Megaceryle alcyon, Cecropis daurica, Geokichla sibirica, Cyanistes caeruleus, Lophophanes cristatus, Periparus ater, Poecile montanus, P. palustris, Pastor roseus, Agropsar sturninus, Melospiza melodia); (3) two scientific names replace others presently on the list due to the recognition of extralimital taxa as species (Turdus eunomus, T. atrogularis); (4) one species is added because of a split from a species already on the Dutch List (Sylvia subalpina); (5) two species become monotypic due to the recognition of an extralimital taxon as species (Tarsiger cyanurus, Oenanthe pleschanka).

Explanation of the spatial distribution patterns in species richness, and especially those of small-ranged species (endemics), bears relevance for studies on evolution and speciation, as well as for conservation management. We test a geometric constraint model, the mid-domain effect (MDE), as a possible explanation for spatial patterns of species richness in Palearctic songbirds (Passeriformes), with an emphasis on the patterns of small-ranged species. We calculated species richness based on digitised distribution maps of phylogenetic species of songbirds endemic to the Palearctic region. Data were plotted and analyzed over a one degree equal area map of the Palearctic Region, with a grid cell area of 4062 km². The emergent biogeographic patterns were analysed with WORLDMAP software. Comparison of the observed richness pattern among 2401 phylogenetic taxa of songbirds in the Palearctic Region with the predictions of a fully stochastic bi-dimensional MDE model revealed that this model has limited empirical support for overall species richness of Palearctic songbirds. Major hotspots were located south of the area where MDE predicted the highest species- richness, while some of the observed coldspots were in the centre of the Palearctic Region. Although small-ranged species are often found in areas with the highest species richness, MDE models have a very restricted explanatory power for the observed species-richness pattern in small-ranged species. Regions with a high number of small-ranged species (endemism hotspots) may contain a unique set of environmental conditions, unrelated to the shape or size of the domain, allowing a multitude of species to co-exist.

In the study of diversity patterns, the Mid-domain effect (MDE), which explains gradients in diversity solely on the basis of geometric constraints, has emerged as a null-model against which other hypotheses can be tested. The effectiveness, measured by its predictive power, of these MDE models appears to depend on the size of the study area and the range-sizes of the taxa considered. Here we test the predictive power of MDE on the species richness patterns of birds and assess its effectiveness for a variety of species range sizes. We digitised distribution maps of 889 species of songbird endemic to the Palearctic, and analysed the emergent biogeographic patterns with WORLDMAP software. MDE had a predictive power of 20% when all songbirds were included. Major hotspots were located south of the area where MDE predicted the highest species-richness, and some of the observed coldspots were in the centre of the Palearctic, contradicting the predictions of the MDE. MDE had little explanatory power (3-19%) for all but the largest range sizes, whereas MDE performed equal or better for the large-ranged species (20-34%) compared to the overall model. Overall MDE did not accurate explain species-richness patterns in Palearctic songbirds. Subsets of larger-range species did not always have a larger predictive power than smaller-range species or the overall model. Despite their low predictive power, MDE models can have a role to play in explaining biogeographic patterns but other variables need to be included in the model as well.

The incidence of hybridisation in birds differs greatly between orders and is expected to be low in or- ders comprising few species. The divers or loons (Gavi- iformes) are a species-poor group in which apparent hybridisation has been reported infrequently. Here we report on a hybrid diver stored in the collections of the Zoological Museum Amsterdam. The bird shows a heterogeneous set of characters, some shared with the putative parent species White-billed Diver Gavia adamsii and Great Northern Diver G. immer, others being intermediate between the two. A Canonical Discrimi- nant Function analysis positions the bird between these two putative parent species, making a hybrid status quite likely. We evaluate the evidence for hybridisation in the order Gaviiformes and conclude that hybridisa- tion has been suspected in four of the five species, though documentation is limited. If this high incidence could be confirmed, it would rank among the highest of any avian order, contradicting the assumption that incidence of hybridisation in small orders is relatively low.

Birds are known to be a group rich in pairs of closely related species that have parapatric or allopatric distributions with relatively narrow contact zones. Here we analyse the geographical distribution of these contact zones for parapatric species pairs of passerine birds of the Palaearctic region. Their contact zones are located mainly in southwestern, northern and central-southern Asia, and in northwestern Africa, with a hotspot in the Middle East. A mid-domain effect null model, where contact zone hotspots are a neutral correlate of continental geometry, had a low explanatory power of 3.8%; the observed distribution of contact zones was not sufficiently predicted. Hypotheses involving range contractions and secondary contact in areas of high topographic and habitat diversity may offer more convincing explanations and offer promising perspectives for future studies.

Background The granivorous house sparrow Passer domesticus is thought to have developed its commensal relationship with humans with the rise of agriculture in the Middle East some 10,000 years ago, and to have expanded with the spread of agriculture in Eurasia during the last few thousand years. One subspecies, P. d. bactrianus, residing in Central Asia, has apparently maintained the ancestral ecology, however. This subspecies is not associated with human settlements; it is migratory and lives in natural grass- and wetland habitats feeding on wild grass seeds. It is well documented that the agricultural revolution was associated with an increase in grain size and changes in seed structure in cultivated cereals, the preferred food source of commensal house sparrow. Accordingly, we hypothesize that correlated changes may have occurred in beak and skull morphology as adaptive responses to the change in diet. Here, we test this hypothesis by comparing the skull shapes of 101 house sparrows from Iran, belonging to five different subspecies, including the non-commensal P. d. bactrianus, using geometric morphometrics. Results The various commensal house sparrow subspecies share subtle but consistent skeletal features that differ significantly from those of the non-commensal P. d. bactrianus. Although there is a marked overall size allometry in the data set, the shape difference between the ecologically differentiated sparrows cannot be explained by differences in size alone. Relative to the size allometry commensal house sparrows exhibit a skull shape consistent with accelerated development (heterochrony), resulting in a more robust facial cranium and a larger, more pointed beak. Conclusion The difference in skull shape and robustness of the beak between commensal and non-commensal house sparrows is consistent with adaptations to process the larger and rachis encapsulated seeds of domesticated cereals among human associated populations.

The number of described species on the planet is about 1.9 million, with ca. 17,000 new species described annually, mostly from the tropics. However, taxonomy is usually described as a science in crisis, lacking manpower and funding, a politically acknowledged problem known as the Taxonomic Impediment. Using data from the Fauna Europaea database and the Zoological Record, we show that contrary to general belief, developed and heavily-studied parts of the world are important reservoirs of unknown species. In Europe, new species of multicellular terrestrial and freshwater animals are being discovered and named at an unprecedented rate: since the 1950s, more than 770 new species are on average described each year from Europe, which add to the 125,000 terrestrial and freshwater multicellular species already known in this region. There is no sign of having reached a plateau that would allow for the assessment of the magnitude of European biodiversity. More remarkably, over 60% of these new species are described by non-professional taxonomists. Amateurs are recognized as an essential part of the workforce in ecology and astronomy, but the magnitude of non-professional taxonomist contributions to alpha-taxonomy has not been fully realized until now. Our results stress the importance of developing a system that better supports and guides this formidable workforce, as we seek to overcome the Taxonomic Impediment and speed up the process of describing the planetary biodiversity before it is too late. doi:10.1371/journal.pone.0036881

A database was created of digitized equal area distribution maps of 3,036 phylogenetic species of Palearctic songbirds. Biogeographic patterns are reported for two data sets: (1) including all passeriform bird species reported as breeding within the boundaries of our study map, (2) passeriform species restricted in their distribution to our study region, thus excluding the partly extra-limital taxa. With respect to the data set excluding partly extra-limital taxa, the average range size is 238 grid cells (grid cell area: 4,062 km2). Analysis of the geographic distribution of species richness for the full data set showed several hotspot regions, mostly located in mountainous areas. The index of range-size rarity identified similar hotspot regions as that for species richness, albeit that the range-size rarity de-emphasized the central Siberian hotspot. Range-size rarity hotspots that are not evident on the measure of species richness concern a great number of islands. Much more prominent on the index of range-size rarity are the Atlas Mountains of northern Africa, the Jabal al Akhdar region in NE Libya, and the eastern border of the Mediterranean. Restricting the analysis of geographic variation to the 25% of the species with smallest ranges resulted in a greatly simplified pattern of hotspots.

The Indo-Pacific region has arguably been the most important area for the formulation of theories about biogeography and speciation, but modern studies of the tempo, mode and magnitude of diversification across this region are scarce. We study the biogeographic history and characterize levels of diversification in the wide-ranging passerine birdErythropitta erythrogasterusing molecular, phylogeographic and population genetics methods, as well as morphometric and plumage analyses. Our results suggest thatE. erythrogastercolonized the Indo-Pacific during the Pleistocene in an eastward direction following a stepping stone pathway, and that sea-level fluctuations during the Pleistocene may have promoted gene flow only locally. A molecular species delimitation test suggests that several allopatric island populations ofE. erythrogastermay be regarded as species. Most of these putative new species are further characterized by diagnostic differences in plumage. Our study reconfirms theE. erythrogastercomplex as a ‘great speciator’: it represents a complex of up to 17 allopatrically distributed, reciprocally monophyletic and/or morphologically diagnosable species that originated during the Pleistocene. Our results support the view that observed latitudinal gradients of genetic divergence among avian sister species may have been affected by incomplete knowledge of taxonomic limits in tropical bird species.