| Species | Phrynosoma douglasii (Bell, 1829) |
| Family | Phrynosomatidae (North American Spiny Lizards and allies) |
| Status | none |
| State Rank | S3 |
| Global Rank | G5 |
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This is a medium-sized lizard with a blunt snout, round flattened body, short legs and a short triangular tail. Maximum size is around 65 mm snout-vent length. Females are significantly larger than males. Spines or “horns” project from the back of the head and fringe-like spines occur on the sides. The dorsal pattern is mottled in white, gray, beige, tan, brown, black and sometimes yellow or orange. Dark blotches occur in transverse rows on the back. The underside is white, sometimes with a yellow or gray wash. Males have enlarged pores (femoral pores) on the midline of the underside of the thighs. Juveniles resemble adults. Overall, horned lizards are rather toad-like in appearance, earning them the Latin name Phrynosoma meaning “toad body,” and the vernacular names “horny toad” or “horned toad.” See Photos Page.
No other lizard occurring in Washington is similar in appearance. See Key Features Page.
Activity starts in late March in the Columbia Basin. Mating takes place soon after emergence in the spring. Young are born live approximately two months after mating. Pygmy short-horned lizards remain active until mid to late October.
Pygmy short-horned lizards occur primarily in the Columbia Basin Ecoregion with some occurrences in the East Cascade and Okanogan ecoregions. See Distribution Map.
For information on the complete range of this species, see NatureServe Explorer.
Pygmy Short-horned Lizards occur primarily in the shrub-steppe. They require soil conditions that allow them to burrow below the surface and substrate that is well-drained. Recent field research in Kittitas County found short-horned lizards to have a disproportionate preference for lithosol terrain. Females in the final month of gestation, however, tended to use loamy and ecotone terrains and also used this habitat for birth sites. Other findings of this study suggest populations may need a variety of substrate types to meet all their needs. In addition to these terrain types, Pygmy Short-horned Lizards in Washington are also known to occur in loamy terrain without lithosols, on vegetated sand dunes and even in some agricultural settings where patches of native habitat are present.
Pygmy Short-horned Lizards are active mid-day during spring and fall but in summer are inactive during the middle of the day when temperatures are at their maximum. Activity periods are generally in the morning and for a short time again in the evening starting around 4:30 PM. They are difficult to find because of their cryptic coloration. Abundance varies from site to site.
The current rank is based on the number of populations reported in the last 20 years and the fact that in some areas this species is quite common. However, anecdotal reports of local declines continue to be voiced.
Observation records are needed from areas without records and areas that have not been reported in the last 20 years. Of particular interest is the Okanogan Valley where no observations have been documented but where the species is believed to occur. Observations that suggest local declines or extirpation are also of interest. Observations can be submitted to the WDFW herp database by contacting Lori Salzer @ salzeljs@dfw.wa.gov.
Megan Lahti recently completed her Master’s Thesis at Central Washington University. Her research focused on the ecology of the Pygmy Short-horned Lizard in Kittitas County. She observed 112 lizards between April and October 2004 and radio-tracked 3 individuals. She found they were associated with habitats having a high proportion of bare ground and sparse shrub and grass cover, such as lithosol terrain. A diet analysis found that Pygmy Short-horned Lizards from her study areas were not ant specialists.
Waterville Elementary school children participate in a NatureMapping project called “Adopt-a-Farmer” that involves the children working with local farmers to collect information on the locations of Pygmy Short-horned Lizards in the Waterville area. Their observations are included on the distribution map.
Habitat conversion for agriculture or other uses is believed to be the main threat to this species. Ants generally make up the majority of the diet with a variety of other insects completing the diet. Management activities that reduce insect abundance may cause local declines in this species.
Hallock (1998), Lahti (2005), Nussbaum et al. (1983), Sherbrooke (2003)
Personal communications: M. Lahti
Website: NatureMapping: http://www.fish.washington.edu/naturemapping/waterville/intro.html
Hallock, L.A. and McAllister, K.R. 2005. Pygmy Short-horned Lizard. Washington Herp Atlas. http://www1.dnr.wa.gov/nhp/refdesk/herp/
Last updated: December 2005