Published May 12, 2018. Updated April 5, 2024. Open access. | Purchase book ❯ |
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 O. petolarius).2
Figure 1: Individuals of Dipsas gracilis from Ecuador: FCAT Reserve, Esmeraldas province (); Las Balsas Reserve, 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 through 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 of slugs,2–4 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
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.
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: www.reptilesofecuador.com. DOI: 10.47051/AJOM3946
Literature cited:
- 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
- Arteaga A, Bustamante L, Guayasamin JM (2013) The amphibians and reptiles of Mindo. Universidad Tecnológica Indoamérica, Quito, 257 pp.
- Field notes, Reptiles of Ecuador book project.
- 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.
- 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
- 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.
- 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: www.iucnredlist.org. DOI: 10.2305/IUCN.UK.2019-2.RLTS.T44581469A44581478.en
- 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.
| Country | Province | Locality | Source |
| Colombia | César | Alto de la Paz | Carvajal-Cogollo et al. 2012 |
| Colombia | Chocó | Río Nercúa | Castaño et al. 2004 |
| Colombia | Nariño | Espriella | iNaturalist; photo examined |
| Colombia | Nariño | Guayacanes | iNaturalist; photo examined |
| Colombia | Nariño | Inguapi | iNaturalist; photo examined |
| Colombia | Nariño | Reserva Natural La Planada | Santander Oliva et al. 2023 |
| Colombia | Nariño | Tangareal del Mira | iNaturalist; photo examined |
| Ecuador | Azuay | Río Patul | Arteaga et al. 2018 |
| Ecuador | Cañar | Manta Real | Arteaga et al. 2018 |
| Ecuador | Cotopaxi | Bosque Privado JDLS | Pellet 2017 |
| Ecuador | Esmeraldas | Alto Tambo | Cisneros-Heredia 2007 |
| Ecuador | Esmeraldas | Angostura | Arteaga et al. 2018 |
| Ecuador | Esmeraldas | Bilsa Biological Reserve | Ortega-Andrade et al. 2010 |
| Ecuador | Esmeraldas | Caimito | Arteaga et al. 2018 |
| Ecuador | Esmeraldas | Canandé | Yánez-Muñoz et al. 2005 |
| Ecuador | Esmeraldas | Centro de Fauna Silvestre James Brown | Photo by Salvador Palacios |
| Ecuador | Esmeraldas | El Aguacate | Arteaga et al. 2018 |
| Ecuador | Esmeraldas | Finca de Germán Cortez | Arteaga et al. 2018 |
| Ecuador | Esmeraldas | Hacienda Equinox | Harvey 2008 |
| Ecuador | Esmeraldas | La Unión | Photo by David Salazar |
| Ecuador | Esmeraldas | Lagarto, Reserva Mayronga | Arteaga et al. 2018 |
| Ecuador | Esmeraldas | Lote Escobar | Yánez-Muñoz 2005 |
| Ecuador | Esmeraldas | Lote Quijano | Yánez-Muñoz 2005 |
| Ecuador | Esmeraldas | Lote Salvadores | Reptiles of Ecuador book database |
| Ecuador | Esmeraldas | Lote Ventanas | Yánez-Muñoz 2005 |
| Ecuador | Esmeraldas | Punta Galeras | Cisneros-Heredia 2007 |
| Ecuador | Esmeraldas | Quingue | Photo by George Fletcher |
| Ecuador | Esmeraldas | Reserva FCAT | Reptiles of Ecuador book database |
| Ecuador | Esmeraldas | Reserva Itapoa | Photo by Raúl Nieto |
| Ecuador | Esmeraldas | San Javier* | Boulenger 1902 |
| Ecuador | Esmeraldas | San Lorenzo | Photo by Carl Franklin |
| Ecuador | Esmeraldas | Tundaloma Lodge | Reptiles of Ecuador book database |
| Ecuador | Esmeraldas | Tundaloma Lodge, 20 km SE of | Arteaga et al. 2013 |
| Ecuador | Esmeraldas | Verdecanandé | Reptiles of Ecuador book database |
| Ecuador | Esmeraldas | Viche | Arteaga et al. 2018 |
| Ecuador | Esmeraldas | Zapallo Grande | Arteaga et al. 2018 |
| Ecuador | Guayas | Cerro de Hayas | Cruz García 2017 |
| Ecuador | Guayas | Guayaquil | Harvey 2008 |
| Ecuador | Guayas | Naranjal | Arteaga et al. 2018 |
| Ecuador | Guayas | Near Guayaquil | USNM 210947; VertNet |
| Ecuador | Imbabura | Cachaco–Lita | Arteaga et al. 2018 |
| Ecuador | Imbabura | Corredor Mashpi–Cotacachi Cayapas | iNaturalist; photo examined |
| Ecuador | Imbabura | Cotacachi Cayapas | Yánez-Muñoz et al. 2004 |
| Ecuador | Imbabura | Paramba | Arteaga et al. 2013 |
| Ecuador | Los Ríos | Buena Fé | Arteaga et al. 2018 |
| Ecuador | Los Ríos | Centro Científico Río Palenque | Arteaga et al. 2018 |
| Ecuador | Los Ríos | Pambilar | Peters 1960 |
| Ecuador | Los Ríos | Patricia Pilar, 14.1 km SE of | Harvey 2008 |
| Ecuador | Los Ríos | San Javier | Boulenger 1902 |
| Ecuador | Los Ríos | Vivero El Cristal | iNaturalist; photo examined |
| Ecuador | Manabí | Ayampe | Reptiles of Ecuador book database |
| Ecuador | Manabí | Estero Gasparito | Arteaga et al. 2018 |
| Ecuador | Manabí | Jama Coaque | Arteaga et al. 2018 |
| Ecuador | Manabí | Lalo Loor | Arteaga et al. 2018 |
| Ecuador | Manabí | Maicito | Arteaga et al. 2018 |
| Ecuador | Manabí | Pacoche Lodge | Reptiles of Ecuador book database |
| Ecuador | Manabí | Pata de Pájaro | Photo by Paul Maier |
| Ecuador | Manabí | Rancho Sinaloa | iNaturalist; photo examined |
| Ecuador | Manabí | Reserva Jama Coaque | Arteaga et al. 2018 |
| Ecuador | Manabí | Río Jama | Photo by Lisa Brunetti |
| Ecuador | Manabí | Tabuga | Photo by Ryan Lynch |
| Ecuador | Manabí | Tito Santos | Hamilton et al. 2005 |
| Ecuador | Pichincha | Bosque El Chalpi–Saguangal | Yánez-Muñoz et al. 2009 |
| Ecuador | Pichincha | Bosque Protector Mashpi | Arteaga et al. 2018 |
| Ecuador | Pichincha | El Abrazo del Árbol | Arteaga et al. 2018 |
| Ecuador | Pichincha | El Monte Lodge | Reptiles of Ecuador book database |
| Ecuador | Pichincha | Finca de Julio Goetschel | Reptiles of Ecuador book database |
| Ecuador | Pichincha | Finca Ecológica Orongo | Arteaga et al. 2018 |
| Ecuador | Pichincha | Gualea | Boulenger 1920 |
| Ecuador | Pichincha | Hacienda La Joya | Cisneros-Heredia 2007 |
| Ecuador | Pichincha | Los Bancos–Puerto Quito | Reptiles of Ecuador book database |
| Ecuador | Pichincha | Mashpi lodge | Arteaga et al. 2018 |
| Ecuador | Pichincha | Nanegalito | Cisneros-Heredia 2007 |
| Ecuador | Pichincha | Pachijal | Harvey 2008 |
| Ecuador | Pichincha | Puerto Quito | Cisneros-Herendia 2007 |
| Ecuador | Pichincha | Rainforest Monterreal | Arteaga et al. 2018 |
| Ecuador | Pichincha | Rancho Suamox | Photo by Rafael Ferro |
| Ecuador | Pichincha | Río Silanche Bird Sanctuary | Arteaga et al. 2013 |
| Ecuador | Pichincha | Road to Mindo | Arteaga et al. 2018 |
| Ecuador | Pichincha | San Miguel de los Bancos | Photo by Wolfgang Wüster |
| Ecuador | Pichincha | Selva Virgen | Arteaga et al. 2013 |
| Ecuador | Pichincha | Vía Mindo–Las Cascadas | Arteaga et al. 2013 |
| Ecuador | Pichincha | Yellow House | Arteaga et al. 2013 |
| Ecuador | Santa Elena | Bosque La Encantadora | Reptiles of Ecuador book database |
| Ecuador | Santa Elena | Reserva Las Balsas | This work; Fig. 1 |
| Ecuador | Santo Domingo de los Tsáchilas | Centinela | Arteaga et al. 2013 |
| Ecuador | Santo Domingo de los Tsáchilas | Finca la Esperanza | Arteaga et al. 2013 |
| Ecuador | Santo Domingo de los Tsáchilas | James Brown Farm | Harvey 2008 |
| Ecuador | Santo Domingo de los Tsáchilas | Reserva Forestal La Perla | Arteaga et al. 2018 |
| Ecuador | Santo Domingo de los Tsáchilas | Reserva Santa Rosa | iNaturalist; photo examined |
| Ecuador | Santo Domingo de los Tsáchilas | Santo Domingo | Cisneros-Heredia 2007 |
| Ecuador | Santo Domingo de los Tsáchilas | Santo Domingo, 8.5 km NW of | Arteaga et al. 2018 |