Horned Toad

The common name “Horned Toad” for Texas Horned Lizards comes from two of its most prominent physical characteristics. Phrynosoma cornutum has two large horns on the center of its head accompanied by lots of smaller horns around it (Bockstanz 2016). It is commonly called a “toad” due to its short flattened body and short legs (Seymour 2016). Spines are found all over the body of the Texas Horned lizard and down its tail (Seymour 2016). Sexual dimorphism between males and females can be seen in two ways, body size with females being larger and the presence of femoral pores on males (Figure2). It has been shown that southern populations of P. cornutum are on average larger that northern populations (Henke & Montemayor 1997). In southern populations
Texas Horned Lizards are designated adults when their snout to vent length (SVL) is 75mm or greater (Henke & Monetmayor 1997) while northern populations adult females are considered mature as 63mm or greater and 49mm or greater for males (Ballinger 1974). The average sizes of our samples most closely resemble the northern populations.