Herpetology Notes, volume 14: 263-268 (2021) (published online on 01 February 2021) The Michoacán Centipede Snake, Tantilla cascadae Wilson and Meyer, 1981 (Squamata: Colubridae): New record for Jalisco, with notes on conservation, biogeography, and a key to the species of the genus in western Mexico Aldo Dávalos-Martínez1,*, Víctor Fernando Záizar-Gutiérrez1, Daniel Cruz-Sáenz2, Eduardo Daniel Roldán- Olvera1, and Larry David Wilson3 Abstract. Tantilla cascadae is a rare centipede snake that inhabits western Mexico and is only known from two localities and three specimens. In this work we report two new specimens from a new locality in the municipality of Tamazula de Gordiano, Jalisco, Mexico. We assess the biogeographical and physiographical component of the species’ distribution, and discuss the conservation status of the species proposing a new IUCN conservation assessment of Endangered. We additionally present a dichotomous key for the genus Tantilla in western Mexico. Keywords. Southern Jalisco, western Michoacán, IUCN, land-use change, mining, avocado, new locality Introduction This species is a member of the Tantilla calamarina species group, which consists of seven species The Michoacán Centipede Snake, Tantilla cascadae distributed along the Pacific versant from northwestern Wilson and Meyer, 1981, is a centipede snake of the Mexico to Costa Rica (Canseco-Márquez et al., 2007b): family Colubridae, endemic to western Mexico. It Tantilla calamarina Cope, 1866; T. cascadae Wilson inhabits oak and pine-oak forest (Duellman, 1961; Cruz- and Meyer, 1981; T. ceboruca Canseco-Márquez, Sáenz et al., 2015) in south-central Jalisco and central Smith, Ponce-Campos, Flores-Villela and Campbell, Michoacán at elevations of 1430–1858 m (Wilson and 2007b; T. coronadoi Hartweg, 1944; T. deppei (Bocourt, Mata-Silva, 2015). The species is classified by the 1883); T. sertula Wilson and Campbell, 2000; and T. Mexican law as Threatened (SEMARNAT, 2010), as vermiformis (Hallowell, 1861) (Wilson and Mata-Silva Data Deficient (DD) by the IUCN Red List (Canseco- 2015). Wilson and Meyer (1981) defined the group by Márquez et al., 2007a), and has an Environmental the presence of a middorsal dark stripe and a dark lateral Vulnerability Score (EVS) of 16 (Johnson et al., 2017). stripe on rows three and four, except in T. deppei, which can have two stripes (one on rows two and three and another in row five) and in T. cascadae, in which the 1 Universidad de Guadalajara, Centro Universitario de Ciencias lateral stripe on rows three and four disappears on the Biológicas y Agropecuarias, km 15.5 Carretera Guadalajara- forepart of the body. Some species of the group also Nogales, Predio Las Agujas, A.P. 1-1919, Zapopan 44101, have the central portion of the parietals covered with a Jalisco, México. spatulate anterior extension of the middorsal dark stripe, 2 Universidad de Guadalajara, Centro Universitario de Ciencias which continues anteriorly to cover the remainder of Biológicas y Agropecuarias, Centro de Estudios en Zoología, the head. On either side of this central head mark a km 15.5 Carretera Guadalajara-Nogales, Predio Las Agujas, postparietal pale spot usually grades posteriorly into A.P. 1-1919, Zapopan 44101, Jalisco, México. 3 Centro Zamorano de Biodiversidad, Escuela Agrícola the ground colour of the dorsolateral area between the Panamericana Zamorano, Departamento de Francisco lateral and median dark stripes and connects anteriorly Morazán, Honduras; 1350 Pelican Court, Homestead, Florida with a narrow extension that proceeds along the side of 33035-1031, USA. the parietal, over the supraocular and onto the side of the * Corresponding author. E-mail: prefrontals and internasals. [email protected] Virtually nothing is known on the natural history of © 2021 by Herpetology Notes. Open Access by CC BY-NC-ND 4.0. Tantilla cascadae except for the note on the specimen 264 Aldo Dávalos-Martínez et al. found in 2000 by Heimes (2016) at the type locality: Comisión Nacional de Áreas Naturales Protegidas “after being exposed from its hiding-place under a small (CONANP). rock the snake tried to retreat quickly into a deeper For the dichotomous key, we defined “western Mexico” subterranean passage”. as the region including the states of Aguascalientes, Tantilla cascadae is a rare species only known from Colima, Jalisco, Michoacán, Nayarit, and Zacatecas. three records: the holotype specimen (AMNH 107389) We obtained morphological and geographic distribution from “Tzaráracua Falls (=Cascada la Tzaráracua), S of data from Reyes-Velasco et al. (2012), Wilson and Uruapán [10.5 km south, according to Duellman, 1961], Mata-Silva (2014) and Heimes (2016). Michoacán, México.” (Wilson and Meyer, 1981), one photographed individual collected by Heimes (2016) Results also from the type locality, and one individual collected New records. Herein we present two new specimens in the municipality of Pihuamo, ca. 20 km southeast of Tantilla cascadae from a new locality in the from the urban area of Pihuamo, Jalisco, Mexico municipality of Tamazula de Gordiano, Jalisco, Mexico (CEZUG-R304; Cruz-Sáenz et al., 2015). (Fig. 1). On 1 July 2019 in Cerro La Mesa, 1.14 km NW In this work we assess the species’ conservation status, of Tamazula de Gordiano (19.6849°N, -103.2572°W; its biogeographic and physiographic regionalisation, WGS 84; elevation 1447 m) we found a female T. and provide to its distribution a new locality with two cascadae (CEZUG-R436); the snake measured 188.03 new specimens. We also provide a dichotomous key for mm in total length with a tail/total length ratio of 0.198. the species of Tantilla in western Mexico. The specimen has 145 ventrals, 42 subcaudals, six supralabials, six infralabials, two postoculars, and a Materials and Methods lateral dark stripe that is barely perceptible on the first third of the body, but is more noticeable towards the We undertook diurnal fieldwork in the municipality posterior end of the body. We kept the snake in captivity of Tamazula de Gordiano in Jalisco, Mexico. We for a few months before euthanising it and we feed it collected the specimens under collection permit SGPA/ with larvae of the mealworm beetle (Tenebrio molitor DGVS/01205/17, granted to Fausto R. Méndez de la Linnaeus, 1758). To our knowledge, this is the first data Cruz by the Secretaria de Medio Ambiente y Recursos on the diet in captivity, and in general, for the species. Naturales. We confirmed the identification of the new On 14 March 2020 in Cerro La Mesa, 1.7 km N of specimens reported (CEZUG-R436-R445) using the Tamazula de Gordiano (19.6907°N, -103.2534°W; keys and descriptions provided by Wilson and Mata- WGS 84; elevation 1358 m), we found another female Silva (2014). Tantilla cascadae (CEZUG-R445). The snake measured We discuss the species’ conservation assessment 192.6 mm in total length with a tail/total length ratio of based on observations in the field made at the three 0.175. The specimen has 141 ventrals, 38 subcaudals, six known localities. We assess the Extent of Occurrence supralabials, six-five infralabials, and two postoculars. (EOO) and Area of Occupancy (AOO) with Geospatial We could not obtain data on the lateral stripe of this Conservation Assessment Tool (GeoCAT; Bachman et specimen. al., 2011) using the auto-value cell width of 13 km and We found both specimens (vouchers CEZUG-R436 we made the IUCN categorisations using the Guidelines and CEZUG-R445) under rocks while conducting for Using the IUCN Red List Categories and Criteria diurnal fieldwork. The habitat of the site is tropical (IUCN Standards and Petitions Committee, 2019). deciduous forest. We deposited the specimens in the We obtained biogeographical data with QGIS vertebrate collection of the Centro de Estudios en Geographic Information System and Google Earth. Zoología of the Universidad de Guadalajara. For assessing the physiographic and biogeographic These records represent third and fourth vouchered provinces of the species, we used the regionalisation specimens of T. cascadae, the second record for the as proposed by Cruz-Sáenz et al. (2017), INEGI state of Jalisco, and the third known locality for the (INEGI, 2020; Biblioteca digital de Mapas. Available species (Fig. 2). These records extend its known from: https://www.inegi.org.mx/app/biblioteca/ficha. distribution 62.3 km north from the Pihuamo locality html?upc=702825267575 [Accessed 20 May 2020)]) (CEZUG-R304) and 129 km northwest from the type and Morrone et al. (2016). We obtained the Natural locality (AMNH 107389). The new locality represents protected areas data from the shape files provided by the lowest elevation recorded for the species (1358 m The Michoacán Centipede Snake: New record for Jalisco, western Mexico 265 Figure 1. (A) Tantilla cascadae (CEZUG R-436) in life. (B) Tantilla cascadae (CEZUG R 445) in life and (C) after euthanasia. Photographs by Eduardo D. Roldán-Olvera (A), Víctor F. Záizar-Gutiérrez (B) and Aldo Dávalos-Martínez (C). for CEZUG-R445), the northernmost locality, and the local tourist activities that take place there, including first record in tropical deciduous forest. littering and the use of horses for recreational purposes. Conservation. Tantilla cascadae is only known from three localities. We estimated an EOO of 2977.385 km2 and an AOO of 500.460 km2. The EOO of the species lies in southeastern Jalisco and western Michoacán. This is one of the areas with the highest rate of illegal land-use change in western Mexico, principally due to the recent and current increase of avocado plantings. Although all the EOO is at risk, each locality has its own environmental problems. Uruapan and its surroundings are attacked constantly by human caused-forest fires and illegal logging for land-use change, whether for developing new urban areas or for preparing new sites for avocado tree planting. The pesticides and herbicides used in agricultural activities also cause environmental damage in the area.