Querétaro, Hidalgo, and Puebla. The type locality given by Baird and Girard is "Between San Pedro and Camanche [sic] Springs, Tex." (Comanche Springs, Texas). Conservation Gauging wild blind snake populations is virtually impossible due to their secretive nature. However, like many other native Texas species, R. dulcis is known to be detrimentally affected by the red imported fire ant. Subspecies The following three subspecies are recognized as being valid. Rena dulcis dulcis Rena dulcis rubellum Rena dulcis supraorbicularis Nota bene: A trinomial authority in parentheses indicates that the subspecies was originally described in a genus other than Rena. References Further reading Adalsteinsson SA, Branch WR, Trape S, Vitt LJ, Hedges SB (2009). "Molecular phylogeny, classification, and biogeography of snakes of the family Leptotyphlopidae (Reptilia, Squamata)". Zootaxa 2244: 1-50. Baird SF, Girard CF (1853). Catalogue of North American Reptiles in the Museum of the Smithsonian Institution. Part I.—Serpents. Washington, District of Columbia: Smithsonian Institution. xvi + 172 pp. (Rena dulcis, new species, pp. 142–143). Behler JL, King FW (1979). The Audubon Society Field Guide to North American Reptiles and Amphibians. New York: Alfred A. Knopf. 743 pp. . (Leptotyphlops dulcis, pp. 583–584 + Plate 464). Boulenger GA (1893). Catalogue of the Snakes in the British Museum (Natural History). Volume I., Containing the Families ... Glauconiidæ ... London: Trustees of the British Museum (Natural History). (Taylor and Francis, printers). xiii + 448 pp. + Plates I–XXVIII. (Glauconia dulcis, p. 65). Conant R (1975). A Field Guide to Reptiles and Amphibians of Eastern and Central North America, Second Edition. Boston: Houghton Mifflin. xviii + 429 pp. + Plates 1-48. (hardcover), (paperback). (Leptotyphlops dulcis, pp. 137–138, Figure 31 + Plate 33 + Map 122). Goin CJ, Goin OB, Zug GR (1978). Introduction to Herpetology, Third Edition. San Francisco: W.H. Freeman and Company. xi + 378 pp. . (Leptotyphlops dulcis, p. 313). Hahn DE (1979). "Leptotyphlops dulcis (Baird and Girard) Texas blind snake". Catalogue of American Amphibians and Reptiles 231: 1-2. Heimes, Peter (2016). Snakes of Mexico: Herpetofauna Mexicana Vol. I. Frankfurt am Main, Germany: Chimaira. 572 pp. . Klauber LM (1940). "The Worm Snakes of the Genus Leptotyphlops in the United States and northern Mexico". Trans. San Diego Soc. Nat. Hist. 9: 87-162. Powell R, Conant R, Collins JT (2016). Peterson Field Guide to Reptiles and Amphibians of Eastern and Central North America, Fourth Edition. Boston and New York: Houghton Mifflin Harcourt. xiv +