Shieldhead Gecko

Reptiles of Ecuador | Sauria | Sphaerodactylidae | Gonatodes caudiscutatus

Spanish common names: Geco cabeciamarillo, salamanquesa cabeciamarilla.

Recognition: ♂♂ 9.4 cm ♀♀ 9.6 cm. In Ecuador, males of Gonatodes caudiscutatus can be identified based on their distinctive head coloration: bright yellow to orange with contrasting dark brown to black reticulations. Females and juveniles are brownish overall and similar to other Ecuadorian dwarf geckos, but they are unique in lacking eyelashes (enlarged scales above the upper eyelid) and a vertical white line above the shoulder.

Natural history: Extremely common. Shieldhead Geckos are diurnal and most active during the middle of the day.1 They are usually found in groups, basking or foraging on tree trunks, buttress roots, walls, and timber.2,3 Throughout its range, Gonatodes caudiscutatus occurs in or around human-modified environments4,5 that are surrounded by plantations or evergreen to deciduous lowland and foothill forests. At night, G. caudiscutatus hides within crevices, or under piles of timber, trash, and debris.3 When threatened, individuals of G. caudiscutatus flee into crevices or under surface objects. If captured, they may shed the tail and lose portions of the skin.3 Shieldhead Geckos feed on termites, beetles, bees, and wasps.1 Females lay a single egg per clutch at intervals of about three weeks.6 These hatch after 90–110 days.6

Conservation: Least Concern.7 Gonatodes caudiscutatus is listed in this category because this species is widely distributed, thrives in human-modified environments, and (presumably) is not undergoing population declines nor facing major immediate threats of extinction.7 Conversely, G. caudiscutatus is an introduced species in the Galápagos Islands4 and the Amazonian slopes of the Andes in Ecuador.2 There is no information regarding how the introduced Shieldhead Gecko interacts with endemic species in Galápagos, but, since it seems to depend on human-modified environments, its impact might be limited.

Special thanks to Anna Kay Smith, our official protector of the Shieldhead Gecko, for symbolically adopting this species and helping bring the Reptiles of Galápagos project to life.

Distribution: Gonatodes caudiscutatus is native to the Chocoan and Tumbesian lowlands of western Ecuador2 and northwestern Peru, and has been introduced into eastern Ecuador2 and the Galápagos.4

Distribution of Gonatodes caudiscutatus in Ecuador Distribution of Gonatodes caudiscutatus in Galápagos

Etymology: The generic name Gonatodes, which comes from the Greek words gonatos (meaning “node”) and odes (meaning “resembling”),8 probably refers to the form of the digits which are slender but in which the joints are prominent as swellings.9 The specific epithet caudiscutatus, which comes from the Latin words cauda (meaning “tail”), scutum (meaning “shield”), and the suffix -atus (meaning “provided with”),8 refers to the broad shields on the underside of the tail of Shieldhead Geckos.10

See it in the wild: On mainland Ecuador, the easiest place to see individuals of Gonatodes caudiscutatus with ~60–100% certainty is the town of Puerto Quito, Pichincha province. In Galápagos, the easiest place to see them is at El Progreso, on San Cristóbal Island, where the geckos are found in abundance during daytime, actively moving on and around buildings.

Authors: Alejandro ArteagaaAffiliation: Biodiversity Field Lab, Khamai Foundation, Quito, Ecuador. and Juan M GuayasaminbAffiliation: Laboratorio de Biología Evolutiva, Universidad San Francisco de Quito (USFQ), Quito, Ecuador.,cAffiliation: Galapagos Science Center, Galápagos, Ecuador.,dAffiliation: Centro de Investigación de la Biodiversidad y Cambio Climático, Universidad Tecnológica Indoamérica, Quito, Ecuador.

Academic reviewers: Anthony Russell.

Photographers: Jose VieiraaAffiliation: Tropical Herping (TH), Quito, Ecuador.,eAffiliation: ExSitu, Quito, Ecuador.

How to cite? Arteaga A, Guayasamin JM (2020) Gonatodes caudiscutatus. In: Arteaga A, Bustamante L, Vieira J, Guayasamin JM (Eds) Reptiles of Ecuador: Life in the middle of the world. Available from: www.reptilesofecuador.com

Literature cited:

  1. Juan Carlos Diaz, unpublished data.
  2. Carvajal-Campos A, Torres-Carvajal O (2012) Gonatodes caudiscutatus (Günther, 1859) (Squamata: Sphaerodactylidae): Distribution extension in Ecuador. Check List 8: 525–527.
  3. Field notes, Reptiles of Ecuador book project.
  4. Olmedo J, Cayot L (1994) Introduced geckos in the towns of Santa Cruz, San Cristóbal and Isabela. Noticias de Galápagos 53: 7–12.
  5. Valencia JH, Garzón K (2011) Guía de anfibios y reptiles en ambientes cercanos a las estaciones del OCP. Fundación Herpetológica Gustavo Orcés, Quito, 268 pp.
  6. Dennis Hluschi, unpublished data.
  7. Caicedo J, Calderón M, Castro F, Hladki AI, Kornacker P, Ramírez-Pinilla M, Renjifo J, Urbina N (2016) Gonatodes caudiscutatus. The IUCN red list of threatened species. Available from: www.iucnredlist.org
  8. Brown RW (1956) Composition of scientific words. Smithsonian Books, Washington, 882 pp.
  9. Russell AP, Baskerville J, Gamble T, Higham TE (2015) The evolution of digit form in Gonatodes (Gekkota: Sphaerodactylidae) and its bearing on the transition from frictional to adhesive contact in Gekkotans. Journal of Morphology 276: 1311–1132.
  10. Günther A (1859) Second list of cold-blooded vertebrata collected by Mr. Fraser in the Andes of western Ecuador. Proceedings of the Zoological Society of London 1859: 402–422.