Sonora mutabilis STICKEL, 1943
Can you confirm these amateur observations of Sonora mutabilis?
|Higher Taxa||Colubridae, Colubrinae, Colubroidea, Caenophidia, Alethinophidia, Serpentes, Squamata (snakes)|
|Common Names||E: Michoacán Ground Snake|
S: Culebra de Tierra Mexicana
|Synonym||Sonora michoacanensis mutabilis STICKEL 1943|
Sonora aequalis SMITH & TAYLOR 1945 (fdie COX et al. 2012)
Sonora michoacanensis mutabilis — ZWEIFEL 1959
Sonora mutabilis — PONCE-CAMPOS et al. 2004
Sonora mutabilis — LINER 2007
Sonora mutabilis — COX et al. 2012
Sonora mutabilis — WALLACH et al. 2014: 681
Sonora (Eosonora) mutabilis — COX et al. 2018: 978
|Distribution||Mexico (Jalisco, Nayarit, Aguascalientes, southern Zacatecas, S Sinaloa)|
Type locality: Magdalena, Jalisco.
Type locality (aequalis): Originally given as ‘Matagalpa, Nicaragua’ (Stickel, 1943), later concluded to be ‘within or somewhat to the east of the ranges of mutabilis and michoacanensis, on the southern part of the Mexican plateau or in the surrounding mountains’ (Stickel, 1943; Echternacht, 1973).
|Types||Holotype: FMNH 105297, paratypes FMNH 105296, BMNH (NHMUK) 1918.104.22.168– BMNH (NHMUK) 1922.214.171.124 and AMNH 19714–19716.|
Holotype: MCZ 6444 [aequalis]
|Diagnosis||Diagnosis: Both bicoloured (formerly aequalis) and tri-coloured forms of this species can be distinguished from S. michoacanensis based on complete banding on the tail and from S. aemula based on the absence of a file-like tail (Fig. 13) [COX et al. 2012].|
Diagnosis: This species is distinguished from Sonora cincta, S. fasciata, S. straminea, S. aemula, S. annulata, S. occipitalis, and S. palarostris by the lack of rostral or caudal adaptations. Both bicoloured and tricoloured forms of this species can be distinguished from S. michoacanensis based on complete banding on the tail (Cox et al. 2018: 978).
Variation: Sonora mutabilis possesses bicoloured (red and black) and tricoloured (red, black, and yellow) morphs (Echternacht 1973). In tricolour morphs, the extent of black interspaces between bands may be quite variable, and bands may have red dorsal or lateral inclusions. Bands may be regular, irregular, or absent ventrally. Morphological measurements and meristic characters are mostly overlapping between S. mutabilis and S. michoacanensis. The hemipenis of S. michoacanensis was described by Stickel (1943). His description was based on one specimen of S. michoacanensis and one of S. mutabilis. Cox et al. (2012) describe the hemipenis of S. mutabilis (Figure 6) and compare it to that of S. michoacanensis (Cope 1895) (Cox et al. 2018: 978).
|Comment||Distribution: Sonora mutabilis Stickel 1943 and S. aequalis Smith and Taylor 1945 are found mostly sympatrically in the foothills of the Sierra Madre Occidental.|
Ponce-Campos et al. (2004) resurrected the name S. aequalis for bicolour ground snakes formerly included under S. mutabilis.
According to current taxonomy, S. mutabilis is tricoloured and S. aequalis is bicoloured (Ponce- Campos et al., 2004), with both considered coralsnake mimics (Echternacht, 1973; Campbell & Lamar, 2004). S. aequalis is best considered a bicolour morph of S. mutabilis and not a valid species [COX et al. 2012].
Variation: Sonora mutabilis possesses bicoloured (red and black) and tricoloured (red, black and yellow) morphs (Echternacht, 1973). In tricolour morphs, the extent of black interspaces between bands may be quite variable, and bands may have red dorsal or lateral inclusions (e.g. Figs 4–6). Bands may be regular, irregular or absent ven- trally. Morphological measurements and meristic charac- ters are mostly overlapping between S. mutabilis and S. michoacanensis (Table 3). The hemipenis of S. michoacanensis was described by Stickel (1943). COX et al. 2012 describe the hemipenis of S. mutabilis and compare it with that of S. michoacanensis (Cope, 1895) [COX et al. 2012].