Horned Lizards (in general) play an important role in many Native American cultures. The Horned Lizard is often seen as a symbol of strength and important as a symbol for healing (Pianka and Hodges). In Mexico the Horned Lizard is believed to help bring rain (Manaster 1997).
Legislation exists in most states to protect Horned Lizards from capture and sale into the pet trade. One obstacle to continued success that P. douglassii faces (as well as other Horned Lizards) is the invasion of some habitat by non-native fire ants. These ants tend to outcompete the natural populations of ants and thus decrease the availability of food (Pianka and Hodges).
Phrynosoma douglassii has no negative effects upon humans.
Humans do not derive any economic benefit from Phrynosoma douglassii.
Phrynosoma douglassii is an insectivore and often considered a dietary specialist with a myrmecophagous diet, or a diet consisting primarily of ants. They are also known to eat a variety of other insects based upon availability, including Coleopterids and Orthopterids. The method of foraging exhibited by P. douglassii is classified as sit-and-wait predation. They are not fast movers and prefer to wait for a prey item to come into their range. They possess uncomplicated homodont dentition which limits their diet to smaller sized prey, such as ants. They will only respond to moving prey items and will consume a variety of prey items dependent upon the local fauna. Due to their larger size, females are able to forage on a broader range of prey sizes than males (Powell and Russell 1983).
Phrynosoma douglassii is the most widely distributed of the Horned Lizards. There are five subspecies which range from southwestern Canada through the western United States to as far south as central Mexico (Manaster 1997).
Biogeographic Regions: nearctic (Native )
Phrynosoma douglassii is suited to a wide range of habitats and can even live at altitudes as high as 900-11,300 feet above sea level (Manaster 1997). It can typically be found throughout its range in dry areas and at high altitudes (Pianka and Hodges).
Phrynosoma douglassii achieves a size in the range of 2.5 to 6 inches in length which may vary between subspecies. The size of the subspecies Phrynosoma douglassii brevirostre reflects the sexual dimorphism of the species, with the larger females growing up to 7.7 cm while males only grow to 5.5 cm (Powell and Russell 1983). Color varies depending upon the animal's surroundings, as their color provides them with camouflage. The color generally ranges from red-brown to yellow-grey. Its body is flat, broad, and almost oval shaped. It has a crown of short spines on the back of the head that extend vertically--these are the horns. The dorsal scales are irregular and there is a single row of spiny scales along each side of its body (Pianka and Hodges; University of Texas).
The mating season for P. douglassii extends from April to June. This species is viviparous and the young are born in July or August after three months of development. An average of twenty-three young are born which are offered no parental care beyond birth. The babies are capable of caring for themselves within a few hours of being born. Because they lack well developed horns at birth, the babies are especially vulnerable to predation (Manaster 1997). Viviparity has possibly evolved in response to the dry and cool mountain climate that these lizards inhabit (Pianka and Hodges).
The pygmy short-horned lizard (Phrynosoma douglasii) is a species of small horned lizard in the family Phrynosomatidae. The species is native to the northwestern United States and adjacent southwestern Canada. Like other horned lizards, it is often called a "horned toad" or "horny toad," but it is not a toad at all. It is a reptile, not an amphibian.[3]
The specific name, douglasii, is in honor of Scottish botanist David Douglas.[4]
The pygmy short-horned lizard is often mistaken for its close relative the greater short-horned lizard (P. hernandesi) which has the same basic body type consisting of small pointed scales around the head and back.[3] Until recent mitochondrial DNA evidence, the greater short-horned lizard was considered to be the same species as the pygmy short-horned lizard. They are now considered distinct species with the pygmy short-horned lizard occupying the northwest portion of the United States and extreme southern British Columbia (now extirpated from Canada).[3] When placed together the two are easily distinguished at full size, the pygmy short-horned lizard being much smaller. The greater short-horned lizard is a highly variable species with different geographic populations exhibiting differences in colour, pattern, and size, with some authorities describing five subspecies. The pygmy short-horned lizard ranges in size from 1.25–2.5 in (3.2–6.4 cm) in snout-to-vent length (SVL) and is a flat-bodied, squat lizard with short spines crowning the head.[5] It has a snub-nosed profile and short legs. The trunk is fringed by one row of pointed scales, while the belly scales are smooth. The colour is gray, yellowish, or reddish-brown, and there are two rows of large dark spots on the back. When threatened or aggressive, its colours become more intense.The pygmy short-horned lizard is also a species at risk in Alberta according to the Committee on the Status of Endangered Wildlife in Canada (COSEWIC).
The diet of P. douglasii varies from different habitats, but mostly among age and sex classes; neonates feed among almost exclusively on ants (89%) while adults consume fewer ants (72%) and yearlings consume the lowest proportion of ants (60%). [6] It is also considered a lizard that tolerates well low temperatures, so it can reach biomes that are not accessible for most other reptiles.[7]
{{cite web}}: CS1 maint: url-status (link) The pygmy short-horned lizard (Phrynosoma douglasii) is a species of small horned lizard in the family Phrynosomatidae. The species is native to the northwestern United States and adjacent southwestern Canada. Like other horned lizards, it is often called a "horned toad" or "horny toad," but it is not a toad at all. It is a reptile, not an amphibian.
