Published May 12, 2018. Updated April 5, 2024. Open access.

Gallery ❯

Graceful Snail-eating Snake (Dipsas gracilis)

Reptiles of Ecuador | Serpentes | Colubridae | Dipsas gracilis

English common name: Graceful Snail-eating Snake.

Spanish common name: Caracolera grácil.

Recognition: ♂♂ 81.9 cmMaximum distance from the snout to the tip of the tail. Snout–vent length=55.4 cm. ♀♀ 76.5 cmMaximum distance from the snout to the tip of the tail. Snout–vent length=53.0 cm..1 In the Chocó rainforest of Ecuador, Dipsas gracilis is the only snake having a combination of large bulging eyes and a pattern of 22–32 broad black body rings separated from each other by narrow light reddish brown interspaces (Fig. 1). This species differs from D. bobridgelyi, which occurs in southwestern Ecuador, by having the head completely black or black scattered with reddish brown markings, whereas in D. bobridgelyi the head is heavily stippled with white and tan pigment, especially on the snout.1 This species differs from Oxyrhopus petolarius by having a blunt snout and bulging eyes (pointed snout and small eyes in the other species).2

Figure showing variation among individuals of Dipsas gracilis

Figure 1: Individuals of Dipsas gracilis from Ecuador: Reserva FCAT, Esmeraldas province (); Reserva Las Balsas, Santa Elena province (); Centro Científico Río Palenque, Los Ríos province (). j=juvenile.

Natural history: Dipsas gracilis is a nocturnal snake that inhabits old-growth to heavily disturbed rainforests, occurring in lower densities in plantations and forest borders near rural areas.2,3 Graceful Snail-Eaters are active at night, especially if it is raining or drizzling.2,3 Their movements throught the foliage are slow, graceful, and generally occur during the first hours of the night on the lower (0.2–3 m above the ground) forest stratum.2,3 However, they may also be seen crossing trails at ground level.2,3 During the day, individuals of D. gracilis have been found resting coiled in tree holes, inside leaf axils, or under surface objects.2,3 The diet in this species consists of snails and probably also on slugs,24 which are presumably immobilized by the use of toxins secreted by the mucous cells of the infralabial glands.5 Nevertheless, all snakes in the genus Dipsas are considered harmless to humans. They never attempt to bite, resorting instead to coiling into a defensive ball posture and producing a musky and distasteful odor when threatened.2,6

Reader support helps us keep the Reptiles of Ecuador book 100% free.

Conservation: Least Concern Believed to be safe from extinction given current circumstances..7 Dipsas gracilis is listed in this category because the species is widely distributed, occurs in several protected areas (at least 21 in Ecuador), and is frequently encountered, suggesting high population densities.7 Although approximately 68.8% of this species’ habitat in western Ecuador has been destroyed, its habitat in Colombia is still largely intact. Therefore, the total current rate of habitat loss throughout the entire range is unlikely to be severe enough to warrant listing D. gracilis in a more threatened category.7

Distribution: Dipsas gracilis is native to the Chocoan lowlands and adjacent Andean foothills of Ecuador (Fig. 2) and Colombia.

Distribution of Dipsas gracilis in Ecuador

Figure 2: Distribution of Dipsas gracilis in Ecuador. The star corresponds to the type locality: San Javier, Esmeraldas province, Ecuador. See Appendix 1 for a complete list of the presence localities included in the map.

Etymology: The name Dipsas comes from the Greek dipsa (=thirst)8 and probably refers to the fact that the bite of these snakes was believed to cause intense thirst. The specific epithet gracilis is a Latin word meaning “slender.”8 It is appropriate for snakes of this species, which are among the thinnest in the genus Dipsas.

See it in the wild: Graceful Snail-eating Snakes can be seen at a rate of about once every few nights, especially during the rainy season in western Ecuador (Dec–May). Prime localities for the species include Mindo, Bilsa Biological Reserve, Lalo Loor Reserve, and Mashpi Rainforest Reserve.

Special thanks to Britton Conway for symbolically adopting the Graceful Snail-Eater and helping bring the Reptiles of Ecuador book project to life.

Click here to adopt a species.

Author: Alejandro ArteagaaAffiliation: Khamai Foundation, Quito, Ecuador.

Photographer: Jose VieirabAffiliation: Tropical Herping (TH), Quito, Ecuador.,cAffiliation: ExSitu, Quito, Ecuador.

How to cite? Arteaga A (2024) Graceful Snail-eating Snake (Dipsas gracilis). In: Arteaga A, Bustamante L, Vieira J (Eds) Reptiles of Ecuador: Life in the middle of the world. Available from: DOI: 10.47051/AJOM3946

Literature cited:

  1. Arteaga A, Salazar-Valenzuela D, Mebert K, Peñafiel N, Aguiar G, Sánchez-Nivicela JC, Pyron RA, Colston TJ, Cisneros-Heredia DF, Yánez-Muñoz MH, Venegas PJ, Guayasamin JM, Torres-Carvajal O (2018) Systematics of South American snail-eating snakes (Serpentes, Dipsadini), with the description of five new species from Ecuador and Peru. ZooKeys 766: 79–147. DOI: 10.3897/zookeys.766.24523
  2. Arteaga A, Bustamante L, Guayasamin JM (2013) The amphibians and reptiles of Mindo. Universidad Tecnológica Indoamérica, Quito, 257 pp.
  3. Field notes, Reptiles of Ecuador book project.
  4. Cadle JE (2005) Systematics of snakes in the Dipsas oreas complex (Colubridae: Dipsadinae) in western Ecuador and Peru, with revalidation of D. elegans (Boulenger) and D. ellipsifera (Boulenger). Bulletin of the Museum of Comparative Zoology 158: 67–136.
  5. De Oliveira L, Jared C, da Costa Prudente AL, Zaher H, Antoniazzi MM (2008) Oral glands in dipsadine “goo-eater” snakes: morphology and histochemistry of the infralabial glands in Atractus reticulatus, Dipsas indica, and Sibynomorphus mikanii. Toxicon 51: 898–913. DOI: 10.1016/j.toxicon.2007.12.021
  6. Cadle JE, Myers CW (2003) Systematics of snakes referred to Dipsas variegata in Panama and Western South America, with revalidation of two species and notes on defensive behaviors in the Dipsadini (Colubridae). American Museum Novitates 3409: 1–47.
  7. Ines Hladki A, Ramírez Pinilla M, Renjifo J, Urbina N, Cisneros-Heredia DF, Brito J, Yánez-Muñoz M, Sánchez J (2019) Dipsas gracilis. The IUCN Red List of threatened species. Available from: DOI: 10.2305/IUCN.UK.2019-2.RLTS.T44581469A44581478.en
  8. Brown RW (1956) Composition of scientific words. Smithsonian Books, Washington D.C., 882 pp.

Appendix 1: Locality data used to create the distribution map of Dipsas gracilis in Ecuador (Fig. 2). Go to the section on symbols and abbreviations for a list of acronyms used. Asterisk (*) indicates type locality.

ColombiaCésarAlto de la PazCarvajal-Cogollo et al. 2012
ColombiaChocóRío NercúaCastaño et al. 2004
ColombiaNariñoEspriellaiNaturalist; photo examined
ColombiaNariñoGuayacanesiNaturalist; photo examined
ColombiaNariñoInguapiiNaturalist; photo examined
ColombiaNariñoReserva Natural La PlanadaSantander Oliva et al. 2023
ColombiaNariñoTangareal del MiraiNaturalist; photo examined
EcuadorAzuayRío PatulArteaga et al. 2018
EcuadorCañarManta RealArteaga et al. 2018
EcuadorCotopaxiBosque Privado JDLSPellet 2017
EcuadorEsmeraldasAlto TamboCisneros-Heredia 2007
EcuadorEsmeraldasAngosturaArteaga et al. 2018
EcuadorEsmeraldasBilsa Biological ReserveOrtega-Andrade et al. 2010
EcuadorEsmeraldasCaimitoArteaga et al. 2018
EcuadorEsmeraldasCanandéYánez-Muñoz et al. 2005
EcuadorEsmeraldasCentro de Fauna Silvestre James BrownPhoto by Salvador Palacios
EcuadorEsmeraldasEl AguacateArteaga et al. 2018
EcuadorEsmeraldasFinca de Germán CortezArteaga et al. 2018
EcuadorEsmeraldasHacienda EquinoxHarvey 2008
EcuadorEsmeraldasLa UniónPhoto by David Salazar
EcuadorEsmeraldasLagarto, Reserva MayrongaArteaga et al. 2018
EcuadorEsmeraldasLote EscobarYánez-Muñoz 2005
EcuadorEsmeraldasLote QuijanoYánez-Muñoz 2005
EcuadorEsmeraldasLote SalvadoresReptiles of Ecuador book database
EcuadorEsmeraldasLote VentanasYánez-Muñoz 2005
EcuadorEsmeraldasPunta GalerasCisneros-Heredia 2007
EcuadorEsmeraldasQuinguePhoto by George Fletcher
EcuadorEsmeraldasReserva FCATReptiles of Ecuador book database
EcuadorEsmeraldasReserva ItapoaPhoto by Raúl Nieto
EcuadorEsmeraldasSan Javier*Boulenger 1902
EcuadorEsmeraldasSan LorenzoPhoto by Carl Franklin
EcuadorEsmeraldasTundaloma LodgeReptiles of Ecuador book database
EcuadorEsmeraldasTundaloma Lodge, 20 km SE ofArteaga et al. 2013
EcuadorEsmeraldasVerdecanandéReptiles of Ecuador book database
EcuadorEsmeraldasVicheArteaga et al. 2018
EcuadorEsmeraldasZapallo GrandeArteaga et al. 2018
EcuadorGuayasCerro de HayasCruz García 2017
EcuadorGuayasGuayaquilHarvey 2008
EcuadorGuayasNaranjalArteaga et al. 2018
EcuadorGuayasNear GuayaquilUSNM 210947; VertNet
EcuadorImbaburaCachaco–LitaArteaga et al. 2018
EcuadorImbaburaCorredor Mashpi–Cotacachi CayapasiNaturalist; photo examined
EcuadorImbaburaCotacachi CayapasYánez-Muñoz et al. 2004
EcuadorImbaburaParambaArteaga et al. 2013
EcuadorLos RíosBuena FéArteaga et al. 2018
EcuadorLos RíosCentro Científico Río PalenqueArteaga et al. 2018
EcuadorLos RíosPambilarPeters 1960
EcuadorLos RíosPatricia Pilar, 14.1 km SE ofHarvey 2008
EcuadorLos RíosSan JavierBoulenger 1902
EcuadorLos RíosVivero El CristaliNaturalist; photo examined
EcuadorManabíAyampeReptiles of Ecuador book database
EcuadorManabíEstero GasparitoArteaga et al. 2018
EcuadorManabíJama CoaqueArteaga et al. 2018
EcuadorManabíLalo LoorArteaga et al. 2018
EcuadorManabíMaicitoArteaga et al. 2018
EcuadorManabíPacoche LodgeReptiles of Ecuador book database
EcuadorManabíPata de PájaroPhoto by Paul Maier
EcuadorManabíRancho SinaloaiNaturalist; photo examined
EcuadorManabíReserva Jama CoaqueArteaga et al. 2018
EcuadorManabíRío JamaPhoto by Lisa Brunetti
EcuadorManabíTabugaPhoto by Ryan Lynch
EcuadorManabíTito SantosHamilton et al. 2005
EcuadorPichinchaBosque El Chalpi–SaguangalYánez-Muñoz et al. 2009
EcuadorPichinchaBosque Protector MashpiArteaga et al. 2018
EcuadorPichinchaEl Abrazo del ÁrbolArteaga et al. 2018
EcuadorPichinchaEl Monte LodgeReptiles of Ecuador book database
EcuadorPichinchaFinca de Julio GoetschelReptiles of Ecuador book database
EcuadorPichinchaFinca Ecológica OrongoArteaga et al. 2018
EcuadorPichinchaGualeaBoulenger 1920
EcuadorPichinchaHacienda La JoyaCisneros-Heredia 2007
EcuadorPichinchaLos Bancos–Puerto QuitoReptiles of Ecuador book database
EcuadorPichinchaMashpi lodgeArteaga et al. 2018
EcuadorPichinchaNanegalitoCisneros-Heredia 2007
EcuadorPichinchaPachijalHarvey 2008
EcuadorPichinchaPuerto QuitoCisneros-Herendia 2007
EcuadorPichinchaRainforest MonterrealArteaga et al. 2018
EcuadorPichinchaRancho SuamoxPhoto by Rafael Ferro
EcuadorPichinchaRío Silanche Bird SanctuaryArteaga et al. 2013
EcuadorPichinchaRoad to MindoArteaga et al. 2018
EcuadorPichinchaSan Miguel de los BancosPhoto by Wolfgang Wüster
EcuadorPichinchaSelva VirgenArteaga et al. 2013
EcuadorPichinchaVía Mindo–Las CascadasArteaga et al. 2013
EcuadorPichinchaYellow HouseArteaga et al. 2013
EcuadorSanta ElenaBosque La EncantadoraReptiles of Ecuador book database
EcuadorSanta ElenaReserva Las BalsasThis work; Fig. 1
EcuadorSanto Domingo de los TsáchilasCentinelaArteaga et al. 2013
EcuadorSanto Domingo de los TsáchilasFinca la EsperanzaArteaga et al. 2013
EcuadorSanto Domingo de los TsáchilasJames Brown FarmHarvey 2008
EcuadorSanto Domingo de los TsáchilasReserva Forestal La PerlaArteaga et al. 2018
EcuadorSanto Domingo de los TsáchilasReserva Santa RosaiNaturalist; photo examined
EcuadorSanto Domingo de los TsáchilasSanto DomingoCisneros-Heredia 2007
EcuadorSanto Domingo de los TsáchilasSanto Domingo, 8.5 km NW ofArteaga et al. 2018