Tantilla melanocephala may attain a total length of 50 cm (20 in), which includes a tail 10 cm (3.9 in) long.[2]
Dorsally, it is pale brown or red, and some specimens also have 3 or 5 narrow brown stripes. The top of the head and neck are black or dark brown. Ventrally, it is yellowish white.[2]
The dorsal scales are smooth, without apical pits, and arranged in 15 rows at midbody.[2]
^ abcdBoulenger, G.A. 1896. Catalogue of the Snakes in the British Museum (Natural History). Volume III., Containing the Colubridæ (Opisthoglyphæ and Proteroglyphæ),... Trustees of the British Museum (Natural History). (Taylor and Francis, Printers.) London. xiv + 727 pp. + Plates I.- XXV. (Homalocranium melanocephalum, pp. 215-217.)
Freiberg, M. 1982. Snakes of South America. T.F.H. Publications. Hong Kong. 189 pp. ISBN0-87666-912-7. (Tantilla melanocephala, p. 111.)
Linnaeus, C. 1758. Systema naturæ per regna tria naturæ, secundum classes, ordines, genera, species, cum characteribus, differentiis, synonymis, locis. Tomus I. Editio Decima, Reformata. L. Salvius. Stockholm. 824 pp. (Coluber melanocephalus, p. 218.)