Galapagos Species Checklist

Geospiza difficilis Sharpe, 1888

Pinzón de pico afilado, Sharp-beaked Ground Finch

Sharp-beaked Ground Finch, Male, on Pinta Island, Galapagos. Photo: Michael Dvorak, CDF.
Sharp-beaked Ground Finch, Male, on Pinta Island, Galapagos. Photo: Michael Dvorak, CDF.

Very similar to Vampire Ground-finch G. septentrionalis of Darwin and Wold, and Genovesa Ground-finch G. acutirostris. Similar to the Small Ground-finch with slightly longer and more pointed beak, with its upper edge almost straight.

Threats Affected by the parasitic fly Philornis downsi that causes heavy chick mortality, though data is missing.

Taxonomy

Domain
Eukaryota

Kingdom
Animalia

Phylum
Chordata

Class
Aves

Order
Passeriformes

Family
Thraupidae

Genus
Geospiza

Species
difficilis

Taxon category: Accepted

Syn.: Geospiza difficilis debilirostris Ridgway, 1894; Geospiza difficilis difficilis Sharpe, 1888; Geospiza difficilis septentrionalis Rothschild & Hartert, 1899; Geospiza nebulosa (Gould, 1837).

Status

Least concern

Ecology

Feeding type: Insectivorous

Invertebrates

Feeding preferences: Feeds mainly on insects and arthropods, also snails in the more humid zones.

Trophic role: Carnivorous

Reproduction mode: Exclusively sexual

Reproductive biology: Male displays in front of a dome shape nest. Only females incubate (three to five eggs), both feed the chicks.

Distribution

Distribution map of specimen collection localities or observation records for this species in our collections database.

Distribution: Present in the highlands of Santiago, Fernandina and Pinta, where the Small Ground Finch occupies the drier zones. In the present, in Darwin, Wolf is other species (G. septentrionalis), and in Genovesa (G. acutirostris). It is now extinct on Santa Cruz.

References

  • Grant, P.R. Grant, B.R. (1980) The breeding and feeding characteristics of Darwin's finches on Isla Genovesa, Galapagos. Ecological Monographs 50:381-410
  • Wiedenfeld, D.A. (2006) Aves, the Galapagos Islands, Ecuador. Check List 2006 2(2): 1-27.
  • Jiménez-Uzcátegui, G. Milstead, B., Márquez, C., Zabala, J., Buitrón, P., Llerena, A., et al. (2007) Galapagos vertebrates: endangered status and conservation actions. Galapagos Report 2006–2007. Charles Darwin Foundation, Puerto Ayora, p. 104–110.
  • Swash, A. Still, R. (2000) Birds, mammals, and reptiles of the Galapagos Islands, an identification guide. Yale University Press, New Haven, Connecticut, USA, 168 pp.
  • Harris, M.P. (1973) The Galápagos avifauna. Condor 75(3): 265-278.
  • Sundevall, C.J. (1871) On birds from the Galápagos Islands. Proceedings of the Zoological Society of London 1871: 124-129.
  • Castro, I. Phillips, A. (1996) A Guide to the Birds of the Galapagos Islands. Christopher Helm Publishers Ltd., London.
  • Swarth, H.S. (1931) The Avifauna of the Galapagos Islands. Occ. Pap. Calif. Acad. Sci. 18: 1-299.
  • Bisconti, M. Landini, W., Bianucci, G., Cantalamessa, G., Carnevale, G. Ragaini, L. & Valleri, G. (2001) Biogeographic relationships of the Galapagos terrestrial biota: parsimony analyses of endemicity based on reptiles, land birds and Scalesia land plants. J. Biogeogr. 28: 495-510.
  • Donohue, K. (2011) Darwin's Finches: Readings in the Evolution of a Scientific Paradigm University of Chicago Press, Chicago, 492 pp.
  • Alatalo, R. V. (1982) Bird Species Distributions in the Galapagos, Ecuador, and Other Archipelagoes: Competition Or Chance?. Ecology 63 (4): 881-887
  • Stern, D. Grant, P. (1996) A phylogenetic reanalysis of allozyme variation among populations of Galápagos finches. Zoological Journal of the Linnean Society 118:119-134.
  • Schluter, D. Grant, P. (1982) The distribution of Geospiza difficilis in relation to G. fuliginosa in the Galápagos Islands: test of three hypothesis. Evolution 36:1213-1226.
  • Schluter, D. Grant, P. (1984) Ecological correlates of morphological evolution in a Darwins Finch Geospiza difficilis. Evolution 38:856-869.
  • Schluter, D. (1982) Distributions of Galápagos ground finches along an altitudinal gradient: the importance of food supply. Ecology 63:1504-1517
  • Schluter, D. (1984) Feeding correlates of breeding and social organization in two Galápagos finches. The Auk 101:59-68.
  • Farrington, H. Lawson, L., Clark, C. & Petren, K. (2014) The evolutionary history of Darwin's finches: speciation, gene flow, and introgression in a fragmented landscape. Evolution doi 10.1111/evo.12484.
  • Grant, B.R. Grant, P.R. (2002) Simulating secondary contact in allopatric speciation: an empirical test of premating isolation. Biological Journal of the Linnean Society 76:545-556.
  • Grant, P.R. Grant, B.R. & Petren, K. (2000) The allopatric phase of speciation: The sharp-beaked ground finch (Geospiza difficilis) on the Galápagos islands. Biological Journal of the Linnean Society 69:287-317.
  • Petren, K. Grant, P., Grant, B., Clack, A. & Lescano, N. (2010) Multilocus genotypes from Charles Darwin’s finches: biodiversity lost since the voyage of the Beagle. ) Philosophical Transactions of the Royal Society of London. Series B, Biological Sciences 365:1009-1018.
  • IUCN (2015) The IUCN Red List of Threatened Species. Version 2015-4. <www.iucnredlist.org>. Downloaded on 20 November 2015.
  • Lamichhaney, S. Berglund, J., Sällman Almén, M., Maqbool, K., Grabherr, M., Martinez-Barrio, A., Promerova, M., Rubin, C.J., Wang, C., Zamani, N., Grant, B.R., Grant, P.R., Webster, M.T., Andersson, L. (2015) Evolution of Darwin’s finches and their beaks revealed by genome sequencing Nature 518: 371-386. doi:10.1038/nature14181
  • Remsen, J.V. Areta, J.I.Jr., Cadena, C.D., Claramunt, S., Jaramillo, A., Pacheco, J.F., Pérez-Emán, J., Robbins, M.B., Stiles, F.G., Stotz, D.F., Zimmer, K. J. (2016) A Classification of the Bird Species of South America. South American Classification Committee. American Ornithologists' Union http://www.museum.lsu.edu/~Remsen/SACCBaseline.htm
  • IUCN (2017) The IUCN Red List of Threatened Species Version 2016-3. <www.iucnredlist.org>. Downloaded on 03 February 2017.

The “Charles Darwin Foundation for the Galapagos Islands”, in French “Fondation Charles Darwin pour les îles Galapagos”, Association International sans but lucratif (“AISBL”), has its registered office located at Drève du Pieuré 19, 1160 Brussels, and is registered under the trade registry of Brussels under the number 0409.359.103.

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