Buff-throated Woodcreeper
Encyclopedia
The Buff-throated Woodcreeper (Xiphorhynchus guttatus) is a resident passerine
bird
found in tropical South America
in the Guiana Shield and disjunctly
in the northern Atlantic Forest. It formerly included the Cocoa Woodcreeper
and the Lafresnaye's Woodcreeper
as subspecies
. Some authorities retain Lafresnaye's position as a subspecies of the Buff-throated Woodcreeper, but the resulting group is polyphyletic (see Systematics and evolution).
is, together with Lafresnaye's Woodcreeper, the largest member of the genus Xiphorhynchus
. The head, neck, mantle and chest are streaked buff
, and the rest of the upperparts, wings and tail are rufous. The underparts are olive-brown. The bill is long, slightly decurved, and hooked at the tip. The upper mandible is dark grey, while the lower mainly is pale greyish-horn. The normal call is a loud chev-re chev-re.
s which feed on ant
s and other insect
s and spider
s. It feeds low in trees, usually alone, but groups will follow columns of army ant
s. The species builds a bark-lined nest in a tree hole or hollow stump and lays two white eggs.
is highly complex. The smaller Cocoa Woodcreeper (X. susurrans) from Central America
and northwestern South America was formerly included in this species, but is now normally considered to be distinct. Of the remaining taxa, the pale-billed and buff-streaked guttatoides group (incl. dorbignyanus) and the dark-billed and whitish-streaked eytoni group (incl. vicinalis and gracilirostris) have often been considered separate species, as the Lafresnaye's Woodcreeper (X. guttatoides) and the Dusky-billed Woodcreeper (X. eytoni). While visually very different, these two groups are now known to form a single clade
(combined under a "broad" Lafresnaye's Woodcreeper, X. guttatoides) separate from the nominate group (guttatus, polystictus and connectens) of X. guttatus, which instead is closer to X. susurrans. Biogeography
and molecular data suggest that the relationship between these subspecies and the taxa now included in X. guttatoides and X. susurrans deserves further study. Depending of the outcome of these studies, the Buff-throated Woodcreeper could be restricted to the southern coastal population, which is endangered
by habitat fragmentation
, making a change in conservation status necessary.
The most likely evolutionary scenario is that from lower Amazonia, the ancestors of Lafresnaye's Woodcreeper spread west- and southwestwards to the Andes, and those of the Buff-throated and Cocoa Woodcreeper downriver and then along the coast of northern South America, where X. susurrans then branched off as the northern lineage. Indeed, it may be that the trans-Andean forms of the latter may constitute yet another good species, Lawrence's Woodcreeper.
Passerine
A passerine is a bird of the order Passeriformes, which includes more than half of all bird species. Sometimes known as perching birds or, less accurately, as songbirds, the passerines form one of the most diverse terrestrial vertebrate orders: with over 5,000 identified species, it has roughly...
bird
Bird
Birds are feathered, winged, bipedal, endothermic , egg-laying, vertebrate animals. Around 10,000 living species and 188 families makes them the most speciose class of tetrapod vertebrates. They inhabit ecosystems across the globe, from the Arctic to the Antarctic. Extant birds range in size from...
found in tropical South America
South America
South America is a continent situated in the Western Hemisphere, mostly in the Southern Hemisphere, with a relatively small portion in the Northern Hemisphere. The continent is also considered a subcontinent of the Americas. It is bordered on the west by the Pacific Ocean and on the north and east...
in the Guiana Shield and disjunctly
Disjunct distribution
In biology, a taxon with a disjunct distribution is one that has two or more groups that are related but widely separated from each other geographically...
in the northern Atlantic Forest. It formerly included the Cocoa Woodcreeper
Cocoa Woodcreeper
The Cocoa Woodcreeper is a passerine bird which breeds in tropical Central and South America in Trinidad, Tobago, northern Colombia and northern Venezuela. It was formerly considered a subspecies of the Buff-throated Woodcreeper .It is typically 23 cm long, and weighs 37 g...
and the Lafresnaye's Woodcreeper
Lafresnaye's Woodcreeper
The Lafresnaye's Woodcreeper is a resident passerine bird found in tropical South America in the western and southern Amazon and adjacent sections of the Cerrado. It is often considered a subspecies of the Buff-throated Woodcreeper, but this combined "species" would be polyphyletic...
as subspecies
Subspecies
Subspecies in biological classification, is either a taxonomic rank subordinate to species, ora taxonomic unit in that rank . A subspecies cannot be recognized in isolation: a species will either be recognized as having no subspecies at all or two or more, never just one...
. Some authorities retain Lafresnaye's position as a subspecies of the Buff-throated Woodcreeper, but the resulting group is polyphyletic (see Systematics and evolution).
Description
With a total length of 27–28 cm (10½-11 in), and a weight of c. 64 g, this woodcreeperWoodcreeper
The woodcreepers comprise a subfamily of sub-oscine passerine birds endemic to the Neotropics. They have traditionally been considered a distinct family Dendrocolaptidae, but most authorities now place them as a subfamily of the ovenbirds...
is, together with Lafresnaye's Woodcreeper, the largest member of the genus Xiphorhynchus
Xiphorhynchus
Xiphorhynchus is a genus of bird in the woodcreeper subfamily . Its monophyly requires confirmation.It contains the following species:* Lesser Woodcreeper, Xiphorhynchus fuscus - formerly in Lepidocolaptes...
. The head, neck, mantle and chest are streaked buff
Buff (colour)
Buff is a pale yellow-brown colour that got its name from the colour of buff leather.Displayed on the right is the colour buff.EtymologyAccording to the Oxford English Dictionary, buff as a descriptor of a colour was first used in the London Gazette of 1686, describing a uniform to be "A Red Coat...
, and the rest of the upperparts, wings and tail are rufous. The underparts are olive-brown. The bill is long, slightly decurved, and hooked at the tip. The upper mandible is dark grey, while the lower mainly is pale greyish-horn. The normal call is a loud chev-re chev-re.
Ecology
Buff-throated Woodcreepers are restricted to humid forest and woodland. The taxa in north-eastern South America (polystictus and connectens) are generally the commonest large woodcreeper within their range, but the nominate taxon (X. g. guttatus), which is retricted to humid tropical Atlantic forest, has a fragmented population and is generally uncommon. They are insectivoreInsectivore
An insectivore is a type of carnivore with a diet that consists chiefly of insects and similar small creatures. An alternate term is entomophage, which also refers to the human practice of eating insects....
s which feed on ant
Ant
Ants are social insects of the family Formicidae and, along with the related wasps and bees, belong to the order Hymenoptera. Ants evolved from wasp-like ancestors in the mid-Cretaceous period between 110 and 130 million years ago and diversified after the rise of flowering plants. More than...
s and other insect
Insect
Insects are a class of living creatures within the arthropods that have a chitinous exoskeleton, a three-part body , three pairs of jointed legs, compound eyes, and two antennae...
s and spider
Spider
Spiders are air-breathing arthropods that have eight legs, and chelicerae with fangs that inject venom. They are the largest order of arachnids and rank seventh in total species diversity among all other groups of organisms...
s. It feeds low in trees, usually alone, but groups will follow columns of army ant
Army ant
The name army ant is applied to over 200 ant species, in different lineages, due to their aggressive predatory foraging groups, known as "raids", in which huge numbers of ants forage simultaneously over a certain area, attacking prey en masse.Another shared feature is that, unlike most ant...
s. The species builds a bark-lined nest in a tree hole or hollow stump and lays two white eggs.
Systematics and evolution
The taxonomyTaxonomy
Taxonomy is the science of identifying and naming species, and arranging them into a classification. The field of taxonomy, sometimes referred to as "biological taxonomy", revolves around the description and use of taxonomic units, known as taxa...
is highly complex. The smaller Cocoa Woodcreeper (X. susurrans) from Central America
Central America
Central America is the central geographic region of the Americas. It is the southernmost, isthmian portion of the North American continent, which connects with South America on the southeast. When considered part of the unified continental model, it is considered a subcontinent...
and northwestern South America was formerly included in this species, but is now normally considered to be distinct. Of the remaining taxa, the pale-billed and buff-streaked guttatoides group (incl. dorbignyanus) and the dark-billed and whitish-streaked eytoni group (incl. vicinalis and gracilirostris) have often been considered separate species, as the Lafresnaye's Woodcreeper (X. guttatoides) and the Dusky-billed Woodcreeper (X. eytoni). While visually very different, these two groups are now known to form a single clade
Clade
A clade is a group consisting of a species and all its descendants. In the terms of biological systematics, a clade is a single "branch" on the "tree of life". The idea that such a "natural group" of organisms should be grouped together and given a taxonomic name is central to biological...
(combined under a "broad" Lafresnaye's Woodcreeper, X. guttatoides) separate from the nominate group (guttatus, polystictus and connectens) of X. guttatus, which instead is closer to X. susurrans. Biogeography
Biogeography
Biogeography is the study of the distribution of species , organisms, and ecosystems in space and through geological time. Organisms and biological communities vary in a highly regular fashion along geographic gradients of latitude, elevation, isolation and habitat area...
and molecular data suggest that the relationship between these subspecies and the taxa now included in X. guttatoides and X. susurrans deserves further study. Depending of the outcome of these studies, the Buff-throated Woodcreeper could be restricted to the southern coastal population, which is endangered
Endangered species
An endangered species is a population of organisms which is at risk of becoming extinct because it is either few in numbers, or threatened by changing environmental or predation parameters...
by habitat fragmentation
Habitat fragmentation
Habitat fragmentation as the name implies, describes the emergence of discontinuities in an organism's preferred environment , causing population fragmentation...
, making a change in conservation status necessary.
The most likely evolutionary scenario is that from lower Amazonia, the ancestors of Lafresnaye's Woodcreeper spread west- and southwestwards to the Andes, and those of the Buff-throated and Cocoa Woodcreeper downriver and then along the coast of northern South America, where X. susurrans then branched off as the northern lineage. Indeed, it may be that the trans-Andean forms of the latter may constitute yet another good species, Lawrence's Woodcreeper.
Subspecies
- X. g. guttatus (Lichtenstein, 1820). Coastal areas of ParaíbaParaíbaParaíba Paraíba Paraíba (Tupi: pa'ra a'íba: "bad to navigation"; Brazilian Portuguese pronunciation: is a state of Brazil. It is located in the Brazilian Northeast, and is bordered by Rio Grande do Norte to the north, Ceará to the west, Pernambuco to the south and the Atlantic Ocean to the east...
to Espírito SantoEspírito SantoEspírito Santo is one of the states of southeastern Brazil, often referred to by the abbreviation "ES". Its capital is Vitória and the largest city is Vila Velha. The name of the state means literally "holy spirit" after the Holy Ghost of Christianity...
-Rio de JaneiroRio de Janeiro (state)Rio de Janeiro is one of the 27 states of Brazil.Rio de Janeiro has the second largest economy of Brazil behind only São Paulo state.The state of Rio de Janeiro is located within the Brazilian geopolitical region classified as the Southeast...
border. - X. g. polystictus (SalvinOsbert SalvinOsbert Salvin FRS was an English naturalist, best known for co-authoring Biologia Centrali-Americana with Frederick DuCane Godman. This was a 52 volume encyclopedia on the natural history of Central America....
& GoodmanFrederick DuCane GodmanFrederick DuCane Godman D.C.L., F.R.S., F.L.S., F.G.S., F.R.G.S., F.E.S., F.Z.S., M.R.I., F.R.H.S., M.B.O.U. was an English lepidopterist, entomologist and ornithologist....
, 1883). OrinocoOrinocoThe Orinoco is one of the longest rivers in South America at . Its drainage basin, sometimes called the Orinoquia, covers , with 76.3% of it in Venezuela and the remainder in Colombia...
drainage from E Vichada DepartmentVichada DepartmentVichada is a department of the Republic of Colombia in South America. Vichada is located in the eastern plains of Colombia, in the Orinoquia region within the Orinoco river basin bordering the Bolivarian Republic of Venezuela to the north and east...
northeastwards, via E VenezuelaVenezuelaVenezuela , officially called the Bolivarian Republic of Venezuela , is a tropical country on the northern coast of South America. It borders Colombia to the west, Guyana to the east, and Brazil to the south...
to the GuyanasGuyanasGuyana is a country in South America.Guyana, Guayana, or Guiana may also refer to:*Guayana Esequiba, the territory of Guyana claimed by Venezuela*Guayana Region, an administrative region of Venezuela...
. - X. g. connectens Todd, 1948. N bank of lower Amazonas from E of ManausManausManaus is a city in Brazil, the capital of the state of Amazonas. It is situated at the confluence of the Negro and Solimões rivers. It is the most populous city of Amazonas, according to the statistics of Brazilian Institute of Geography and Statistics, and is a popular ecotourist destination....
to AmapáAmapáAmapá is one of the states of Brazil, located in the extreme north, bordering French Guiana and Suriname to the north. To the east is the Atlantic Ocean, and to the south and west is the Brazilian state of Pará. Perhaps one of the main features of the state is the River Oiapoque, as it was once...
. Doubtfully distinct from polystictus.