Rock horned lizard
|rock horned lizard|
The rock horned lizard or Ditmars' horned lizard (Phrynosoma ditmarsi) is a species of phrynosomatid lizard endemic to Sonora in northern Mexico, south of the Arizona border. Bearing the shortest horns of all the horned lizards, it lives in thorn-scrub and deciduous Sinaloan woodlands. The rock horned lizard was "lost" to science for about 65 years. It has a unique habitat preference and limited distribution. It also had a very imprecise holotype locality record which made it difficult to locate. An extraordinary effort by Vincent Roth based on a cross-correlational analysis of gut contents from only three specimens led to its rediscovery.
The rock horned lizard has its occipital and temporal horns reduced to flaring expansions. It has a deep and narrow occipital notch and a high postorbital ridge. The mandibles of Phrynosoma ditmarsi feature a large vertical expansion. It has a bare tympanum in the anterior neck fold posterior to a vertical row of four spines. One row of the rock horned lizard's lateral abdominal fringe scales is surrounded by prominent scales.
- Frost, D. R.; Hammerson, G. A.; Gadsden, H.; Sherbrooke, W. (2007). ""Phrynosoma ditmarsi "". The IUCN Red List of Threatened Species. doi:10.2305/IUCN.UK.2007.RLTS.T64074A12741807.en.
- Beolens, Bo; Watkins, Michael; Grayson, Michael (2011). The Eponym Dictionary of Reptiles. Baltimore: Johns Hopkins University Press. pp. xiii + 296. ISBN 978-1-4214-0135-5. (Phrynosoma ditmarsi, p. 73).
- Lowe CH, Robinson MD, Roth VD (1971). "A Population of Phrynosoma ditmarsi from Sonora, Mexico". J. Arizona Acad. Sci. 6 (4): 275–277.
- Stejneger L (1906). "A New Lizard of the Genus Phrynosoma, from Mexico". Proceedings of the United States National Museum 29: 565–567. (Phrynosoma ditmarsi, new species).