The Maranon spinetail (''Synallaxis maranonica'') is a
Critically Endangered
An IUCN Red List critically endangered (CR or sometimes CE) species is one that has been categorized by the International Union for Conservation of Nature as facing an extremely high risk of extinction in the wild. As of December 2023, of t ...
species of
bird
Birds are a group of warm-blooded vertebrates constituting the class (biology), class Aves (), characterised by feathers, toothless beaked jaws, the Oviparity, laying of Eggshell, hard-shelled eggs, a high Metabolism, metabolic rate, a fou ...
in the Furnariinae subfamily of the ovenbird
family
Family (from ) is a Social group, group of people related either by consanguinity (by recognized birth) or Affinity (law), affinity (by marriage or other relationship). It forms the basis for social order. Ideally, families offer predictabili ...
Ecuador
Ecuador, officially the Republic of Ecuador, is a country in northwestern South America, bordered by Colombia on the north, Peru on the east and south, and the Pacific Ocean on the west. It also includes the Galápagos Province which contain ...
and
Peru
Peru, officially the Republic of Peru, is a country in western South America. It is bordered in the north by Ecuador and Colombia, in the east by Brazil, in the southeast by Bolivia, in the south by Chile, and in the south and west by the Pac ...
.
Taxonomy and systematics
The Maranon spinetail was previously treated as a subspecies of the plain-crowned spinetail (''S. gujanensis''). Recognition of plumage, vocal, and genetic differences led to their separation.Derryberry, E. P., S. Claramunt, G. Derryberry, R. T. Chesser, J. Cracraft, A. Aleixo, J. Pérez-Emán, J. V. Remsen, Jr., and R. T. Brumfield. (2011). Lineage diversification and morphological evolution in a large-scale continental radiation: the Neotropical ovenbirds and woodcreepers (Aves: Furnariidae). Evolution 65(10):2973–2986. https://doi.org/10.1111/j.1558-5646.2011.01374.x The Marañon spinetail is
monotypic
In biology, a monotypic taxon is a taxonomic group (taxon) that contains only one immediately subordinate taxon. A monotypic species is one that does not include subspecies or smaller, infraspecific taxa. In the case of genera, the term "unisp ...
.
Description
The Maranon spinetail is long and weighs . The sexes have the same plumage. Adults have a dark brownish gray face and forehead. Their crown and upper back are dark grayish brown that become more rufescent brown by the rump and uppertail
coverts
A covert feather or tectrix on a bird is one of a set of feathers, called coverts (or ''tectrices''), which cover other feathers. The coverts help to smooth airflow over the wings and tail.
Ear coverts
The ear coverts are small feathers behind t ...
. Their wings are dark rufous with dark fuscous tips on the flight feathers. Their tail is dark rufous; it is graduated and the feathers have blunt tips. Their throat is pale grayish, their breast darker brownish gray, their belly a lighter brownish gray, and their flanks gray with an olive tinge. Their iris is brown, their
maxilla
In vertebrates, the maxilla (: maxillae ) is the upper fixed (not fixed in Neopterygii) bone of the jaw formed from the fusion of two maxillary bones. In humans, the upper jaw includes the hard palate in the front of the mouth. The two maxil ...
black to dark gray, their
mandible
In jawed vertebrates, the mandible (from the Latin ''mandibula'', 'for chewing'), lower jaw, or jawbone is a bone that makes up the lowerand typically more mobilecomponent of the mouth (the upper jaw being known as the maxilla).
The jawbone i ...
blue-gray, and their legs and feet gray to olive. Juveniles have faint dark scallops on the breast and belly and a pinkish yellow mandible.Remsen, Jr., J. V. and C. J. Sharpe (2020). Marañon Spinetail (''Synallaxis maranonica''), version 1.0. In Birds of the World (J. del Hoyo, A. Elliott, J. Sargatal, D. A. Christie, and E. de Juana, Editors). Cornell Lab of Ornithology, Ithaca, NY, USA. https://doi.org/10.2173/bow.marspi3.01 retrieved November 22, 2023
Distribution and habitat
The Maranon spinetail is found in the valley of the
Marañón River
The Marañón River (, , ) is the principal or mainstem source of the Amazon River, arising about 160 km (100 miles) to the northeast of Lima, Peru, and flowing northwest across plateaus 3,650 m (12,000 feet) high, it runs through a deeply ero ...
from far southeastern Ecuador's
Zamora-Chinchipe Province
Zamora Chinchipe (), Province of Zamora Chinchipe is a province of the Republic
of Ecuador, located at the southeastern end of the Amazon Basin, which shares borders with the Ecuadorian provinces of Azuay and Morona Santiago to the north, Loja ...
south into the northern parts of Peru's departments of
Cajamarca
Cajamarca (), also known by the Quechua name, ''Kashamarka'', is the capital and largest city of the Cajamarca Region as well as an important cultural and commercial center in the northern Andes. It is located in the northern highlands of Per ...
and Amazonas. It inhabits the undergrowth of semihumid
gallery forest
A gallery forest is one formed as a corridor along rivers or wetlands, projecting into landscapes that are otherwise only sparsely treed such as savannas, grasslands, or deserts. The gallery forest maintains a more temperate microclimate above th ...
,
secondary forest
A secondary forest (or second-growth forest) is a forest or woodland area which has regenerated through largely natural processes after human-caused Disturbance (ecology), disturbances, such as Logging, timber harvest or agriculture clearing, or ...
, and deciduous woodlands along rivers, and occurs less often at the edges of humid forest. In elevation it ranges between in Ecuador and in Peru.
Behavior
Movement
The Maranon spinetail is a year-round resident throughout its range.
Feeding
The Maranon spinetail feeds on
arthropod
Arthropods ( ) are invertebrates in the phylum Arthropoda. They possess an arthropod exoskeleton, exoskeleton with a cuticle made of chitin, often Mineralization (biology), mineralised with calcium carbonate, a body with differentiated (Metam ...
s. It usually forages in pairs, gleaning its prey from the ground, foliage, and small branches up to about above the ground.
Breeding
Nothing is known about the Maranon spinetail's breeding biology.
Vocalization
The Maranon spinetail's song is "a very slow-paced, somewhat nasal 'kieeuuw...keeeu' ", often with several seconds between phrases. It is sung by both sexes.
Status
The
IUCN
The International Union for Conservation of Nature (IUCN) is an international organization working in the field of nature conservation and sustainable use of natural resources. Founded in 1948, IUCN has become the global authority on the status ...
originally assessed the Maranon spinetail as Vulnerable but since 2012 has rated it Critically Endangered. It has a limited range and its estimated population of 6000 to 15,000 mature individuals is believed to be decreasing. "Much of its woodland habitat has progressively deteriorated owing to widespread and long-term cultivation of land within the Marañón drainage. The spread of oil-palm plantations, cattle-ranching and logging all seriously threaten its remaining habitat, with oil extraction a potential future problem." It is considered uncommon in Ecuador and locally fairly common in Peru, but because it is difficult to see it may be overlooked.