Tapaculo

Taxobox
name = Tapaculos


image_width = 240px
image_caption = Crested Gallito, "Rhinocrypta lanceolata"
regnum = Animalia
phylum = Chordata
classis = Aves
ordo = Passeriformes
subordo = Tyranni
familia = Formicariidae (but see below)

subdivision_ranks = Genera
subdivision =
*"Acropternis"
*"Eugralla"
*"Liosceles"
*"Melanopareia"
*"Merulaxis"
*"Myornis"
*"Psilorhamphus"
*"Pteroptochos"
*"Rhinocrypta"
*"Scelorchilus"
*"Scytalopus"
*"Teledromas"

The tapaculos are a group of small suboscine passeriform birds with numerous species, found mainly in South America and with the highest diversity in the Andean regions. Three species, the Choco, the Pale-throated and the Silvery-fronted Tapaculo, are found in southern Central America.

Description

Tapaculos are small to medium-sized birds, with a total length ranging from 10-24 cm (4-9½ in). These are terrestrial species that fly only poorly on their short wings. They have strong legs, well-suited to their habitat of grassland or forest undergrowth. The tail is cocked and pointed towards the head, and the name "tapaculo" possibly derives from Spanish for "cover your behind". Another possible explanation is that it originates from the Chilean name for the White-throated Tapaculo, simply "Tapaculo", which is an onomatopoeic reference to its commonly heard song.

While the majority of the family are small blackish or brown birds there are some larger and more colourful species. They are best located and — in the case of "Scytalopus spp." — identified by their vocalisations.

They feed on insects, seeds and other soft plant material with their pointy bills, and will scratch on the ground like a pheasant. Most species lay two or three white eggs in a covered location, whether it be a burrow, a hole in a tree, or a domed nest.

Threats and conservation

Some species have highly localized distributions, and being poor fliers, they easily become isolated in small populations. BirdLife International currently (2007) consider one species vulnerable ("Scytalopus panamensis"), three species endangered ("S. iraiensis", "S. rodriguezi" and "S. robbinsi"), and two species critically endangered ("S. psychopompus" and "Merulaxis stresemanni"). The two critically endangered species are restricted to Atlantic forest of eastern Brazil, and were only recently rediscovered after several years without any records.

Taxonomy

The tapaculos were traditionally placed in a distinct family Rhinocryptidae; more recent research (Irestedt "et al." 2002, Rice 2005a,b) indicates that according to analysis of mt and nDNA sequence data, the tapaculos might be better merged into the Formicariidae as tribe Rhinocryptini, as they are closer to the antthrushes than either is to the true antpittas.

Alternatively, the latter might be raised to family status. In this case, it would be possible to maintain the tapaculos as a separate family too, but it would seem altogether more warranted to consider them a subfamily of the Formicariinae "sensu stricto", which would be called Rhinocryptinae.

Whether this latter approach, the placement as a tribe in a tapaculo-antthrush Formicariinae subfamily, or maintenance as a separate family is to be preferred depends on whether the true antpittas are closer to the tapaculos and true antbirds, or rather to the "Pittasoma" "gnatthrushes" and other gnateaters and the true antbirds. There are some, albeit very tentative, indications that the latter may indeed be the case, which would be reflected in the placement of the tapaculos as subfamily Rhinocryptinae, with the Formicariinae being restricted to the true antthrushes (Rice 2005a).

It must be noted that apparently not "all" tapaculo genera would have to be moved to the formicariids (Irestedt "et al." 2002). As the type genus "Rhinocrypta" certainly would, any distinct genera (such as the peculiar crescent-chests) would need a new family name.

Taxonomy of "Scytalopus"

The species-limits within the genus "Scytalopus" is among the most complex matters in Neotropical ornithology. They are highly cryptic, and identification using visual features often is impossible. Vocal and biochemical data is typically needed to clarify the taxonomic status of the various populations. Several new species have been described in recent years (e.g. "S. stilesi" and "S. rodriguezi" from Colombia). Maurício (2005) found that the otherwise relatively well known "S. speluncae" actually consisted of two species, of which the southern was described as a new species; "S. pachecoi", while the northern retained "S. speluncae". It was further suggested that "S. speluncae" included yet another undescribed species, but more work was needed on that matter. Furthermore, work by Raposo "et al." (2006) cast doubt into the use of the scientific name "S. speluncae" for the "Mouse-colored Tapaculo" in the Serra do Mar region.

Examining the type specimen of "S. speluncae" (Ménétriés, 1835) resulted in them attributing this to a population further inland, which previously was included within "S. novacapitalis" (vocally, this population is closer to "S. pachecoi"). This meant that the tapaculo from the Serra do Mar region had to receive a new name; "S. notorius" ("notorius" to illustrate its problematic taxonomical history). CBRO (Comitê Brasileiro de Registros Ornitológicos) has recommended moving both the scientific and the English name to the "new" inland species, which then would become the Mouse-coloured Tapaculo ("S. speluncae"), while the species previously known under that name would become the Serra do Mar Tapaculo ("S. notorius").

Additionally, still undescribed species are known to exist (e.g. the "Apurimac Tapaculo" and "Millpo Tapaculo"; both from Peru), while some species as currently defined actually may include several species (e.g. the southern population of the Large-footed Tapaculo may represent a yet undescribed species). The confusing situation is perhaps best illustrated by the fact that only 10 species were recognized in this genus in 1970 (Krabbe & Schulenberg, 2003), while the figure now is more than four times as high.

pecies list

Genera allied with antthrushes
*Genus "Pteroptochos", the huet-huets
** Black-throated Huet-huet, "Pteroptochos tarnii"
** Chestnut-throated Huet-huet, "Pteroptochos castaneus"
** Moustached Turca, "Pteroptochos megapodius"
*Genus "Scytalopus" (some 40-45 species)
*Genus "Scelorchilus"Placement here needs confirmation.]
** White-throated Tapaculo, "Scelorchilus albicollis"
** Chucao Tapaculo, "Scelorchilus rubecula"
*Genus "Rhinocrypta"
** Crested Gallito, "Rhinocrypta lanceolata"
*Genus "Liosceles"
** Rusty-belted Tapaculo, "Liosceles thoracicus"

Probably a distinct family N.N.
*Genus "Melanopareia", the crescent-chests
** Collared Crescent-chest, "Melanopareia torquata"
** Olive-crowned Crescent-chest, "Melanopareia maximiliani"
** Elegant Crescent-chest, "Melanopareia elegans"
** Maranon Crescent-chest, "Melanopareia maranonica"
*Genus "Teledromas"
** Sandy Gallito, "Teledromas fuscus"

Placement unresolved
*Genus "Psilorhamphus"
** Spotted Bamboowren, "Psilorhamphus guttatus"
*Genus "Merulaxis", the bristlefronts
** Slaty Bristlefront, "Merulaxis ater"
** Stresemann's Bristlefront, "Merulaxis stresemanni"
*Genus "Eugralla"
** Ochre-flanked Tapaculo, "Eugralla paradoxa"
*Genus "Myornis"
** Ash-colored Tapaculo, "Myornis senilis"
*Genus "Acropternis"
** Ocellated Tapaculo, "Acropternis orthonyx"

References

* Irestedt, Martin; Fjeldså, Jon; Johansson, Ulf S. & Ericson, Per G.P. (2002): Systematic relationships and biogeography of the tracheophone suboscines (Aves: Passeriformes). "Molecular Phylogenetics and Evolution" 23(3): 499–512. doi|10.1016/S1055-7903(02)00034-9 (HTML abstract)

* Krabbe, N, and Schulenberg, T. (2003). Family Rhinocryptidae (Tapaculos). Pp. 748-787 in: del Hoyo, J., Elliott, A., and Christie, D. eds. (2003). "Handbook of Birds of the World." Vol. 8. Broadbills to Tapaculos. Lynx Edicions, Barcelona. ISBN 84-87334-50-4

* Maurício, G, (2005). "Taxonomy of the southern population in the Scytalopus speluncae group, with the description of a new species and remarks on the sytematics and biogeography of the complex (Passeriformes: Rhinocryptidae)." Ararajuba. 13(1): 7-28.

* Raposo, M., Stopiglia, R., Loskit, V., and Kirwin, G. (2006). "The correct use of the name Scytalopus speluncae (Ménétriés, 1835), and the description of a new species of Brazilian tapaculo (Aves: Passeriformers: Rhinocryptidae)." Zootaxa 1271: 37-56.

* Rice, Nathan H. (2005a): Phylogenetic relationships of antpitta genera (Passeriformes: Formicariidae). "Auk" 122(2): 673-683. [English with Spanish abstract] DOI:10.1642/0004-8038(2005)122 [0673:PROAGP] 2.0.CO;2 [http://www.ansp.org/research/biodiv/ornithology/pdf/antpitta-phylogeny.pdf PDF fulltext]

* Rice, Nathan H. (2005b): Further Evidence for Paraphyly of the Formicariidae (Passeriformes). "Condor" 107(4): 910-915. [English with Spanish abstract] DOI|10.1650/7696.1 [http://www.ansp.org/research/biodiv/ornithology/pdf/antbird-paraphyly.pdf PDF fulltext]

* [http://www.birdlife.org/datazone/species/index.html?action=SpcHTMFindResults.asp&hdnAction=SEARCH&hdnPageMode=0&cboFamily=109&txtGenus=&txtSpecies=&txtCommonName=&cboRegion=-2&cboCountry=-2 Status of the members of "Rhinocryptidae"] BirdLife International (2007).

* Comitê Brasileiro de Registros Ornitológicos: [http://www.cbro.org.br/CBRO/ List of Birds in Brazil]

Footnotes

External links

* [http://ibc.hbw.com/ibc/phtml/familia.phtml?idFamilia=111 Tapaculo videos] on the Internet Bird Collection