Leptotyphlops dulcis is a member of Leptotyphlopidae, a clade of small, slender, fossorial snakes commonly known as slender blindsnakes, threadsnakes or wormsnakes. All but one of the approximately 93 species of Leptotyphlopidae are contained within the genus Leptotyphlops. In the New World, this genus ranges throughout most of South America (excluding Chile, southern Argentina, and southern Peru), Central America and Mexico, with two species (L. dulcis and L. humilis) extending northward into the southwestern United States. Also, six species are endemic to islands of the West Indies, and several mainland species are known from islands along the coasts of Mexico and Central America. In the Old World, Leptotyphlops is distributed throughout Africa and the Arabian Peninsula, with two species (L. blanfordi and L. macrorhynchus) ranging eastward into northwestern India. In addition, three species (L. filiformis, L. macrurus and L. wilsoni) are endemic to the island of Socotra in the northwestern Indian Ocean, and a few mainland species are known to inhabit several islands off the coast of Africa (e.g., Pemba, Bioco). The genus Rhinoleptus includes only a single species, R. koniagui, which is known from Guinea and Senegal.
The single most striking external characteristic of leptotyphlopids is their extremely small size. Although a small number of "giant" species occasionally reach lengths of over 300 mm (e.g., Leptotyphlops humilis, L. melanotermus, L. occidentalis, L. tricolor, L. weyrauchi, Rhinoleptus koniagui), the majority are much smaller, ranging between 100 and 250 mm in total body length. Most species reach maximum body widths of only 2 to 5 mm, and many weigh less than 1 g as adults.
Like other blindsnakes (anomalepidids and typhlopids), leptotyphlopids have highly reduced eyes, a cylindrical body, smooth, uniformly sized body scales, a small, ventrally placed mouth, and a short tail bearing a sharp apical spine. Leptotyphlopids are predominantly fossorial in their habits. They are most commonly found in shallow soil, amidst leaf litter and other surface debris, or beneath stones or logs. They are also discovered occasionally within rotten logs, ant hills and termitaria. Like other scolecophidians, leptotyphlopids feed exclusively on small invertebrate prey, most commonly ant brood and termites. They rely heavily on chemoreception to find their prey. They are able to follow the pheromone trails of ants and termites with relative ease, allowing them to locate large colonies of these abundant social insects in almost any environment. Once they enter these colonies, they go into a feeding frenzy and quickly gorge themselves, often eating hundreds of prey items in a single meal. They ingest their prey using a bizarre mandibular raking mechanism, in which the front half of the lower jaw is flexed rapidly in and out of the mouth to ratchet prey into the esophagus.
Leptotyphlops dulcis is native to the southwestern United States (southern Kansas, central and western Oklahoma, southeastern Colorado, central and western Texas, southern New Mexico, southeastern Arizona) and northeastern Mexico (northeastern Sonora, northeastern Chihuahua, Coahuila, Nuevo Leon, Tamaulipas, northern Veracruz, San Luis Potosi, northern Zacatecas). It is a relatively large species by leptotyphlopid standards, reaching a maximum adult length of over 270 mm.
Additional Information on the Skull
Click on the thumbnails below for a detailed description of the skull in standard anatomical views.
About the Species
This specimen was collected on FM 181 1.8 miles north of Texas Highway 115 in Andrews County, Texas by T. J. LaDuc and C. R. Harrison on 31 May 2001. It was made available to the University of Texas High-Resolution X-ray CT Facility for scanning by Dr. Timothy Rowe of the Jackson School of Geosciences, The University of Texas at Austin. Funding for scanning and image processing was provided by a National Science Foundation Digital Libraries Initiative grant to Dr. Rowe. Funding for additional image processing was provided by a National Science Foundation Assembling the Tree of Life grant (EF-0334961), The Deep Scaly Project: Resolving Squamate Phylogeny using Genomic and Morphological Approaches, to Drs. Jacques Gauthier of Yale University, Maureen Kearney of the Field Museum, Jessie Maisano of The University of Texas at Austin, Tod Reeder of San Diego State University, Olivier Rieppel of the Field Museum, Jack Sites of Brigham Young University, and John Wiens of SUNY Stonybrook.
About this Specimen
The specimen was scanned by Matthew Colbert on 5 November 2003 along the coronal axis for a total of 701 slices. Each 512x512 pixel slice is 0.012 mm thick, with an interslice spacing of 0.012 mm and a field of reconstruction of 5 mm. The imagery presented here was generated using the first 563 slices.
Abdeen, A. M., A. M. Abo-Taira and M. M. Zaher. 1991a. Further studies on the ophidian cranial osteology: The skull of the Egyptian blind snake Leptotyphlops cairi (Family Leptotyphlopidae). I. The cranium. A: The median dorsal bones, bones of the upper jaw, circumorbital series and occipital ring. Journal of the Egyptian German Society of Zoology 5: 417-437.
Abdeen, A. M., A. M. Abo-Taira and M. M. Zaher. 1991b. Further studies on the ophidian cranial osteology: The skull of the Egyptian blind snake Leptotyphlops cairi (Family Leptotyphlopidae). I. The cranium. B: The otic capsule, palate and temporal bones. Journal of the Egyptian German Society of Zoology 5: 439-455.
Abdeen, A. M., A. M. Abo-Taira and M. M. Zaher. 1991c. Further studies on the ophidian cranial osteology: The skull of the Egyptian blind snake Leptotyphlops cairi (Family Leptotyphlopidae). II. The lower jaw and the hyoid apparatus. Journal of the Egyptian German Society of Zoology 5: 457-467.
Broadley, D. G. and S. Broadley. 1999. A review of the African worm snakes from south of Latitude 12ºS (Serpentes: Leptotyphlopidae). Syntarsus 5: 1-36.
Brock, G. T. 1932. The skull of Leptotyphlops (Glauconia) nigricans. Anatomischer Anzeiger 73: 199-204.
Fabrezi, M., A. Marcus and G. Scrocchi. 1985. Contribución al conocimiento de los Leptotyphlopidae de Argentina. I. Leptotyphlops weyrauchi y Leptotyphlops albipuncta. Cuadernos de Herpetología, Asociación Herpetológica Argentina 1: 1-20.
Haas, G. 1930. Über das Kopfskelett und die Kaumuskulatur der Typhlopiden und Glauconiiden. Zoologische Jahrbücher, Abteilung für Anatomie und Ontogenie der Tiere 52: 1-94.
Haas, G. 1959. Bemerkungen über die Anatomie des Kopfes und des Schädels der Leptotyphlopidae (Ophidia), speziell von L. macrorhynchus Jan. Vierteljahrsschrift der Naturforschenden Gesellschaft in Zürich 104: 90-104.
Kley, N. J. 2001. Prey transport mechanisms in blindsnakes and the evolution of unilateral feeding systems in snakes. American Zoologist 41: 1321-1337.
Kley, N. J. 2003. Slender blindsnakes (Leptotyphlopidae). In M. Hutchins, J.B. Murphy and N. Schlager (eds.), Grzimek’s Animal Life Encyclopedia, 2nd edition. Vol. 7, Reptiles, pp. 373-377. Gale Group, Farmington Hills, MI.
Kley, N. J. 2006. Morphology of the lower jaw and suspensorium in the Texas blindsnake, Leptotyphlops dulcis (Scolecophidia: Leptotyphlopidae). Journal of Morphology 267:494-515.
Kley, N. J., and E. L. Brainerd. 1999. Feeding by mandibular raking in a snake. Nature 402:369-370.
Langebartel, D. A. 1968. The hyoid and its associated musculature in snakes. Illinois Biological Monographs 38: 1-156.
List, J. C. 1966. Comparative osteology of the snake families Typhlopidae and Leptotyphlopidae. Illinois Biological Monographs 36: 1-112.
McDowell, S. B. 1967. Osteology of the Typhlopidae and Leptotyphlopidae: a critical review. Copeia 1967: 686-692.
McDowell, S. B., Jr. and C. M. Bogert. 1954. The systematic position of Lanthanotus and the affinities of the anguinomorphan lizards. Bulletin of the American Museum of Natural History 105: 1-142.
Rieppel, O. 1979. The braincase of Typhlops and Leptotyphlops (Reptilia: Serpentes). Zoological Journal of the Linnean Society 65: 161-176.
Rieppel, O. and H. Zaher. 2000. The intramandibular joint in squamates, and the phylogenetic relationships of the fossil snake Pachyrhachis problematicus Haas. Fieldiana: Geology, New Series 43: 1-69.
Underwood, G. 1967. A Contribution to the Classification of Snakes. British Museum (Natural History) Publication Number 653. British Museum (Natural History), London.
Zaher, H. and O. Rieppel. 1999. Tooth implantation and replacement in squamates, with special reference to mosasaur lizards and snakes. American Museum Novitates 3271: 1-19.
See video clips of Leptotyphlops dulcis feeding from the research of Dr. Nate Kley (Field Museum of Natural History
A page on blind snake predation of ants by Dr. Barry Sullender (Rice University)
Three-dimensional volumetric renderings of the skull with the lower jaw removed and of the isolated left mandible. All are less than 2mb.