- Lectotype: USNM 2671a, adult ♂, collected by John H. Clark in late April or early May 1851. [designated by Axtell (1981: 211)]
- Type locality: “Between Indianola and San Antonio (Texas)”, restricted to “9 miles southwest of Somerset, Atascosa County”, Texas, by Smith & Taylor (1950: 85), restriction contested and changed to “the area within a circle, with a 12 Km diameter, centered at coordinates 29º16'20"N-98º09'50"” by Axtell (1981: 213).
- Baird, S.F. & Girard, C. 1852. Characteristics of some new reptiles in the Museum of the Smithsonian Institution. Second Part. Proceedings of the Academy of Natural Sciences of Philadelphia 6: 125–129. BHL Reference page.
- Axtell, R.W. 1981. Holbrookia propinqua: Type specimens, collector, his route, and restriction of locality, with comments on Baird's "Reptiles of the Boundary" as an important taxonomic reference. Journal of Herpetology 15(2): 211–217. doi: 10.2307/1563383
- Uetz, P. & Hallermann, J. 2019. Holbrookia propinqua. The Reptile Database. Accessed on 16 October 2019.
- Hammerson, G.A., Lavin, P. & Mendoza Quijano, F. 2007. IUCN: Holbrookia propinqua (Least Concern). The IUCN Red List of Threatened Species 2007: e.T64066A12733768. doi: 10.2305/IUCN.UK.2007.RLTS.T64066A12733768.en