Báez’ Snail-eating Snake (Dipsas oswaldobaezi)

Reptiles of Ecuador | Serpentes | Colubridae | Dipsas oswaldobaezi

English common name: Báez’ Snail-eating Snake.

Spanish common name: Caracolera de Oswaldo Báez.

Recognition: ♂♂ 46.2 cmMaximum distance from the snout to the tip of the tail. Snout–vent length=34.8 cm. ♀♀ 55 cmMaximum distance from the snout to the tip of the tail. Snout–vent length=42.8 cm..¹ In its area of distribution, Dipsas oswaldobaezi can be identified by having a light brown dorsum with 55–63 drab to brown black-edged middorsal blotches that, in the anterior third of the body, form complete “saddles” that reach onto the ventral scales (Fig. 1).¹ This species differs from D. oreas by having blotches that are wider near the top of the dorsum (proper “saddles”) rather than narrower near the top.^1,2 From Leptodeira ornata, it differs by having dorsal blotches that reach onto the ventral scales (confined to the dorsum in L. ornata).³

Figure showing an adult female individual of Dipsas oswaldobaezi

Figure 1: Adult female of Dipsas oswaldobaezi from La Ceiba Reserve, Loja province, Ecuador.

Natural history: Dipsas oswaldobaezi is a crepuscular and nocturnal snake that inhabits old-growth to moderately disturbed dry lowland shrublands and seasonally dry forests.¹ The species also occurs in pastures and may occasionally venture into rural gardens.^1,4 At night, Báez’ Snail-Eaters move actively but slowly at ground level or on shrubs up to 2 m above the ground.¹ During the day, they remain hidden under the leaf-litter.¹ Nothing is known about the diet in this species, but snakes of the genus Dipsas in general feed almost exclusively on snails and slugs. Although some snail-eaters produce saliva that is toxic to mollusks,⁵ these snakes are considered harmless to humans. They never attempt to bite, resorting instead to musking and flattening the body while expanding the head to simulate a triangular shape.

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Conservation: Vulnerable Considered to be facing a high risk of extinction in the mid-term future.. Dipsas oswaldobaezi is a recently described species.¹ Therefore, its status has not been formally evaluated by the IUCN Red List. Here, it is proposed to be assigned into the VU category because the species’ extent of occurrence is estimated to be smaller than 10,000 km² and it is known only from ten localities effectively corresponding to four patches of forest lacking connectivity between them. The habitat of D. oswaldobaezi is severely fragmented and declining in extent and quality due to deforestation.¹

Distribution: Dipsas oswaldobaezi is native to an area of approximately 8,605 km² in the Tumbesian lowlands and adjacent Andean foothills of southwestern Ecuador (Fig. 2) and northwestern Perú.

Figure 2: Distribution of Dipsas oswaldobaezi in Ecuador. The star corresponds to the type locality: Quebrada El Faique, Loja province. 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)⁶ and probably refers to the fact that the bite of these snakes was believed to cause intense thirst. The specific epithet oswaldobaezi honors Dr. Oswaldo Báez, a renowned Ecuadorian biologist and researcher who has dedicated his life to the teaching of science, scientific thinking, and the conservation of nature. Oswaldo Báez has played a major role in science education in Ecuador through many popular science articles and books.¹

See it in the wild: Báez’ Snail-eating Snakes are rarely recorded, usually no more than once every few months at any given locality. However, at La Ceiba Reseve, they may be seen more frequently. These snakes may be spotted as they cross trails and roads in areas of dry forest, especially around sunset.

Author: Alejandro Arteaga^aAffiliation: Khamai Foundation, Quito, Ecuador.

Photographer: Jose Vieira^bAffiliation: Tropical Herping (TH), Quito, Ecuador.^,^cAffiliation: ExSitu, Quito, Ecuador.

How to cite? Arteaga A (2024) Báez’ Snail-eating Snake (Dipsas oswaldobaezi). 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/GLQC8920

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
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.
Torres-Carvajal O, Sánchez-Nivicela JC, Posse V, Celi E (2020) A new species of cat-eyed snake (Serpentes: Dipsadinae: Leptodeirini) from the Andes of southern Ecuador. Zootaxa 4895: 357–380. DOI: 10.11646/zootaxa.4895.3.3
Field notes, Reptiles of Ecuador book project.
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
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 oswaldobaezi 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
Ecuador	El Oro	Arenillas	Arteaga et al. 2018
Ecuador	El Oro	Guabillo	Arteaga et al. 2018
Ecuador	El Oro	Huaquillas	Arteaga et al. 2018
Ecuador	Loja	Bramaderos	Photo by Sebastián Valverde
Ecuador	Loja	Catamayo	Cadle 2007
Ecuador	Loja	Jorupe Reserve	iNaturalist; photo examined
Ecuador	Loja	Laipuna	Arteaga et al. 2018
Ecuador	Loja	Quebrada El Faique	Arteaga et al. 2018
Ecuador	Loja	Reserva La Ceiba-Pilares	Arteaga et al. 2018
Ecuador	Loja	Vía a Comunidad Las Cochas del Almendro	Torres-Carvajal et al. 2019
Perú	Piura	Piura	Arteaga et al. 2018