The dorsal scales are small, pointed, and keeled, as the common name implies.

Adults may attain 62 mm (2+1⁄2 in) snout to vent length (SVL), 140 mm (5+1⁄2 in) total length.

[1] Holbrookia propinqua occurs in the Tamaulipan mezquital ecoregion where it is known from various vegetation zones in south Texas, including mixed oak forest, mesquite brush-lands, cleared fields, coastal prairie, and grasslands, although always where bands of Tertiary sand outcrops or sandy stream-side deposits are found.

It is perhaps most common in the loose and shifting sands of beaches, barrier islands, and the Coastal Sand Plain of Southern Texas.

It also ranges into northeast Mexico but it is highly restricted to the narrow zone of sand dunes of the coastal beaches, peninsulas, and barrier islands of Tamaulipas and southward to the vicinity of Veracruz, Veracruz.