Published May 12, 2018. Updated March 30, 2024. Open access. | Gallery ❯ |
Andean Snail-eating Snake (Dipsas andiana)
Reptiles of Ecuador | Serpentes | Colubridae | Dipsas andiana
English common name: Andean Snail-eating Snake.
Spanish common name: Caracolera andina.
Recognition: ♂♂ 69 cmMaximum distance from the snout to the tip of the tail. Snout–vent length=48.8 cm. ♀♀ 84.3 cmMaximum distance from the snout to the tip of the tail. Snout–vent length=67.3 cm..1,2 In its area of distribution, Dipsas andiana is the only snake having a clearly defined dark ∩-shaped mark on the back of the head. It also has a blunt, extremely prominent head and a characteristic pattern of dark blotches on a pale brown dorsum (Fig. 1).1,2 This species differs from D. elegans and D. oreas by virtue of the the distinctive head mark (absent in the other species).1,2
Figure 1: Individuals of Dipsas andiana from Ecuador: FCAT Reserve, Esmeraldas province (); Centro Científico Río Palenque, Los Ríos province (). j=juvenile.
Natural history: Dipsas andiana is a nocturnal snake that inhabits old-growth to heavily disturbed rainforests and seasonally dry forests, usually close to streams and rivers.1,2 The species also ventures into pastures, cacao plantations, banana groves, and rural gardens.2 Andean Snail-Eaters are active at night, especially if it is raining or drizzling. They move actively but slowly at ground level on soil and leaf-litter, or on vegetation 10–300 cm above the ground.2 They feed on native slugs and snails as well as on the introduced Giant African Snail (Achatina fulica).1–3 During the day, these snakes remained coiled and hidden among understory vegetation. Dipsas andiana has been found overseas in shipments of bananas from Ecuador. At least five specimens found their way to New York in the period 1939–1958.1 Andean Snail-Eaters are harmless to humans; they are extremely docile and never attempt to bite. However, they coil into a defensive posture and produce a musky and distasteful odor when threatened.1,2 There is a recorded instance of predation on a member of this species by the viper Bothrops asper.4 The clutch size in this species consists of 3–5 eggs laid inside holes in the ground.3,5
Conservation: Near Threatened Not currently at risk of extinction, but requires some level of management to maintain healthy populations..6 Dipsas andiana is listed in this category primarily because the species occurs as fragmented populations over an area where approximately 67% of the forest cover has been destroyed and transformed into cattle pastures, palm oil plantations, and human settlements.6 Therefore, D. andiana may qualify for a threatened category in the near future if its habitat continues to be degraded and fragmented.
Distribution: Dipsas andiana is endemic to an area of approximately 52,735 km2 in western Ecuador (Fig. 2).
Figure 2: Distribution of Dipsas andiana in 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) and probably refers to the fact that the bite of these snakes was believed to cause intense thirst.7 The specific epithet andiana comes from the Latin andinus (=pertaining to the Andes).7 This species was described based on a specimen that was labeled as having been found in Quito.1
See it in the wild: Andean 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, Buenaventura Biological Reserve, and Mashpi Rainforest Reserve.
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) Andean Snail-eating Snake (Dipsas andiana). 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/ERHE2385
Literature cited:
- 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.
- 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.
- Gabrysova B, Aznar González de Rueda J, Barrio-Amorós CL (2020) Bothrops asper (Terciopelo): diet/ophiophagy. Herpetological Review 51: 859–860.
- Photo by Jose Vieira.
- Cisneros-Heredia DF, Almendáriz A (2017) Dipsas andiana. The IUCN Red List of threatened species. Available from: www.iucnredlist.org. DOI: 10.2305/IUCN.UK.2017-2.RLTS.T50951272A50951279.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 andiana in Ecuador (Fig. 2). Go to the section on symbols and abbreviations for a list of acronyms used.
| Country | Province | Locality | Source |
| Ecuador | Azuay | Sarayunga | Arteaga et al. 2013 |
| Ecuador | Azuay | Vía Molleturo–Manta Real | Arteaga et al. 2013 |
| Ecuador | Bolívar | Balzapamba | Cadle & Myers 2003 |
| Ecuador | Bolívar | Gavilanes | iNaturalist; photo examined |
| Ecuador | Cañar | El Chorro | Photo by Alex Angulo |
| Ecuador | Cañar | Hidroeléctrica Ocaña | Arteaga et al. 2018 |
| Ecuador | Carchi | Reserva Siete Cascadas | Reptiles of Ecuador book database |
| Ecuador | Carchi | Sendero Awa | Yánez-Muñoz 2005 |
| Ecuador | Cotopaxi | Bosque Privado JDLS | Gabrysova et al. 2020 |
| Ecuador | Cotopaxi | Las Pampas | Arteaga et al. 2018 |
| Ecuador | Cotopaxi | Vía Pucayacu–Sigchos | Arteaga et al. 2013 |
| Ecuador | El Oro | Cascadas de Manuel | Garzón-Santomaro et al. 2019 |
| Ecuador | El Oro | Caserío Tigre 1 | Arteaga et al. 2013 |
| Ecuador | El Oro | Lote Tituana | Reptiles of Ecuador book database |
| Ecuador | El Oro | Marcabelí | Garzón-Santomaro et al. 2019 |
| Ecuador | El Oro | Reserva Biológica Buenaventura | Arteaga et al. 2018 |
| Ecuador | El Oro | Torata, 4 km SW of | iNaturalist; photo examined |
| Ecuador | Esmeraldas | Alto Tambo | Cisneros-Heredia 2007 |
| Ecuador | Esmeraldas | Bilsa Biological Reserve | Ortega-Andrade et al. 2010 |
| Ecuador | Esmeraldas | Caimito | Reptiles of Ecuador book database |
| Ecuador | Esmeraldas | Campamento 106 | iNaturalist; photo examined |
| Ecuador | Esmeraldas | Canandé Biological Reserve | Reptiles of Ecuador book database |
| Ecuador | Esmeraldas | Cerro Ceibo | Arteaga et al. 2013 |
| Ecuador | Esmeraldas | Lote Salvadores | This work; Fig. 1 |
| Ecuador | Esmeraldas | Reserva FCAT | Reptiles of Ecuador book database |
| Ecuador | Esmeraldas | Río San Francisco | Cisneros-Heredia 2007 |
| Ecuador | Esmeraldas | Tabuche | Arteaga et al. 2013 |
| Ecuador | Loja | Río Cochurco | Arteaga et al. 2013 |
| Ecuador | Los Ríos | Babahoyo | Cadle & Myers 2003 |
| Ecuador | Los Ríos | Centro Científico Río Palenque | This work; Fig. 1 |
| Ecuador | Los Ríos | Hacienda Cerro Chico | Arteaga et al. 2013 |
| Ecuador | Manabí | Ayampe | iNaturalist; photo examined |
| Ecuador | Manabí | Boca de Palmito | Reptiles of Ecuador book database |
| Ecuador | Manabí | Bosque Seco Lalo Loor | Arteaga et al. 2013 |
| Ecuador | Manabí | Cantalapiedra | Photo by Manuel Mejía |
| Ecuador | Manabí | Cerro Pata de Pájaro | Photo by Paul Hamilton |
| Ecuador | Manabí | El Achiote | Reptiles of Ecuador book database |
| Ecuador | Manabí | La Crespa | iNaturalist; photo examined |
| Ecuador | Manabí | Pacoche Lodge | Reptiles of Ecuador book database |
| Ecuador | Manabí | Pile | iNaturalist; photo examined |
| Ecuador | Manabí | Puerto López, 5 km NW of | Arteaga et al. 2018 |
| Ecuador | Manabí | Rancho Stephany | iNaturalist; photo examined |
| Ecuador | Manabí | Reserva Jama Coaque | Lynch et al. 2016 |
| Ecuador | Manabí | Reserva Tito Santos | Hamilton et a. 2005 |
| Ecuador | Manabí | Three Forests Trail | Photo by Paul Maier |
| Ecuador | Manabí | Zapote | Arteaga et al. 2013 |
| Ecuador | Pichincha | Dos Ríos, 4 km NE of | Cadle & Myers 2003 |
| Ecuador | Pichincha | Hacienda La Hesperia | Brouwer 2018 |
| Ecuador | Pichincha | Hacienda La Joya | Arteaga et al. 2018 |
| Ecuador | Pichincha | Hacienda Yellow House | Arteaga et al. 2013 |
| Ecuador | Pichincha | Kapari Lodge | Reptiles of Ecuador book database |
| Ecuador | Pichincha | La Palma | Cadle & Myers 2003 |
| Ecuador | Pichincha | Los Bancos–Valle Hermoso road | Arteaga et al. 2018 |
| Ecuador | Pichincha | Lower Mashpi | Reptiles of Ecuador book database |
| Ecuador | Pichincha | Mashpi Lodge | Arteaga et al. 2018 |
| Ecuador | Pichincha | Mindo Night Walks | iNaturalist; photo examined |
| Ecuador | Pichincha | Puerto Quito | Cadle & Myers 2003 |
| Ecuador | Pichincha | Rancho Suamox | Photo by Rafael Ferro |
| Ecuador | Pichincha | Río Toachi | Arteaga et al. 2013 |
| Ecuador | Pichincha | San Miguel de los Bancos | Cisneros-Heredia 2007 |
| Ecuador | Pichincha | Tandayapa | Arteaga et al. 2018 |
| Ecuador | Santa Elena | Comuna Loma Alta | Cisneros-Heredia 2007 |
| Ecuador | Santo Domingo de los Tsáchilas | Bosque Protector La Perla | iNaturalist; photo examined |
| Ecuador | Santo Domingo de los Tsáchilas | Dos Ríos | Cisneros-Heredia 2007 |
| Ecuador | Santo Domingo de los Tsáchilas | Santo Domingo de los Colorados | Cadle & Myers 2003 |