Arremon

Abstract: The identification of mechanisms that have generated biodiversity is one of the major tasks in biogeography and evolutionary biology. Here, using a set of environmental variables and historical presence records, we assessed whether closely related allopatric lineages in the Arremon brunneinucha (Aves: Passerellidae) complex are either more ecologically similar or different throughout their distribution in Mesoamerica. Using PCA-env approximation, niche similarity tests, and comparative approaches, we analysed niche evolution in this species complex and the relative role of geographic and environmental factors on shaping lineage divergence. Our results suggest that most (95.24%) of the evolutionary lineages included in the A. brunneinucha complex have a null to low climatic niche overlap (Schoener’s D = 0.0–0.2), in addition, our data rejected the hypothesis of niche similarity among these lineages in 17 paired comparison cases (80.94%). We found that allopatric and nearly parapatric lineages both show evidence that their ecological niches have been maintained by sharp climatic gradients. These patterns suggest that divergence in these evolutionary lineages has been promoted due to different environmental conditions and evolutionary pressures, which in concert with geographical barriers to gene flow, have led to diversification in the A. brunneinucha complex throughout Mesoamerica.

Abstract: A total of 376 individuals of 35 bird species belonging to the families Cardinalidae, Emberizidae, Fringillidae, and Thraupidae were examined for chewing lice in Costa Rica in 2004, 2009 and 2010. A total of 128 birds of 19 species were parasitised with 17 species of Myrsidea. Descriptions and illustrations are given for four new species of Myrsidea. These new species and their type hosts are: Myrsidea bidentata ex Piranga bidentata (Cardinalidae), M. dolejskae ex Arremon brunneinucha (Emberizidae), M. roubalovae ex Ramphocelus sanguinolentus (Thraupidae), and M. rubica ex Habia rubica (Cardinalidae). Records of new host-louse associations are: Chlorospingus ophthalmicus (Emberizidae) and Euphonia hirundinacea (Fringillidae) for M. violaceae, Ramphocelus costaricensis (Thraupidae) for M. fusca, and Tangara dowii (Thraupidae) for M. bonariensis. Records of ten other louse species of the genus Myrsidea from birds belonging to these families are also presented and discussed.

Abstract: A new highland species of chestnut-capped Arremon brush-finch is described from the Sierra Madre del Sur of central Guerrero. This form, although indistinguishable in external phenotype from adjacent populations to the east in Oaxaca, is dramatically differentiated in mitochondrial DNA sequence characters, and quite unexpectedly is the sister lineage to the very distinct (phenotype and genotype), central-Mexican-endemic A. virenticeps. Nuclear sequence differentiation in the new lineage is more subtle than in mitochondrial DNA, but is on par with that in the well-marked A. virenticeps. The new species is thus distinct from its sister lineage in genotype and phenotype, and clearly distinct from all other forms in genotype; however, it has retained an ancestral external phenotype similar to other members of the broader A. brunneinucha complex.

Abstract: The following species are added to Colombia's bird checklist: Manx Shearwater Puffinus puffinus (observations), Black-headed Gull Chroicocephalus ridibundus (observations), Forster’s Tern Sterna forsteri (photographic record), Grey-backed Hawk Leucopternis occidentalis (observations), Rio Orinoco Spinetail Synallaxis beverlyae (newly described) and Yellow-cheeked Becard Pachyramphus xanthogenys (new record). First confirmed records for Colombia of White Tern Gygis alba (photograph), Point-tailed Palmcreeper Berlepschia rikeri (sonogram and photograph) and Lesser Wagtail-Tyrant Stigmatura napensis (sonogram) are published. A first sight record for Colombia of Blue-mantled Thornbill Chalcostigma stanleyi and photographs of the first specimen record of Ringbilled Gull Larus delawarensis are published. The following species are removed as no records were found: Ecuadorian Trogon Trogon mesurus and Olivaceous Siskin Carduelis olivacea. Various splits are recognised, resulting in changes of name for some species and the recognition of the following ‘new’ species for Colombia: Highland Motmot Momotus aequatorialis, Whooping Motmot Momotus subrufescens, Fulvous Antshrike Frederickena fulva, Choco Tyrannulet Zimmerius albigularis, Paramo Tapaculo Scytalopus opacus, Black-headed Brush-Finch Arremon atricapillus, Colombian Brush-Finch Arremon basilicus and Phelps’ Brush-Finch Arremon perijanus. San Andres Mockingbird Mimus magnirostris is removed due to recognition of a lump. Rationales for splits of Colombian Chachalaca Ortalis columbiana, Chestnut-mandibled Toucan Ramphastos swainsonii and Venezuelan Tyrannulet Zimmerius improbus are presented, including sonograms showing vocal support for the splits in the case of Ortalis and Zimmerius. Various species change category within the list, following a review of record documentation. Several amendments to genus and species names, English names and linear order are made. Following these changes, the Colombian checklist stands at 1,878 species, of which 1,802 have 'confirmed' records. Resumen Las siguientes especies se agregan al listado de aves de Colombia: Puffinus puffinus (basado en observaciones), Chroicocephalus ridibundus (observaciones), Sterna forsteri (registro fotografico), Leucopternis occidentalis (observaciones), Synallaxis beverlyae (recientement descrita) y Pachyramphus xanthogenys (observaciones). Registros “confirmados” para Colombia de Gygis alba (fotografia), Berlepschia rikeri (sonograma y fotografia) y Stigmatura napensis (sonograma), son presentados. Un primer registro para Chalcostigma stanleyi y fotografias del primer especimen de Larus delawarensis en Colombia tambien son presentados. Las siguientes especies fueron quitadas ya que no se encontraron registros de ellos en Colombia: Trogon mesurus y Carduelis olivacea. Varias separaciones son reconocidas, resultado en un cambio de nombre para algunas especies y el reconocimiento de las siguientes "nuevas" especies para Colombia: Momotus aequatorialis, Momotus subrufescens, Frederickena fulva, Zimmerius albigularis, Scytalopus opacus, Arremon atricapillus, Arremon basilicus y Arremon perijanus. Mimus magnirostris, se retira debido al reconocimiento de una fusion. Se incluyen detalles sobre la propuesta separacion de Ortalis columbiana, Ramphastos swainsonii y Zimmerius improbus. Se presentan un estudio de sonogramas en apoyo a las separaciones de Ortalis y Zimmerius. Varias especies cambian de categoria dentro del listado, tras una revision de bibliografia. Se efectuaron varias modificaciones en los nombres al nivel de genero y especie, en los nombres en ingles y en el orden linear. A raiz de estos cambios, el listado de especies en Colombia asciende a 1,878 de los cuales 1,802 cuetan con registros “confirmados”.