The roundtail horned lizard (''Phrynosoma modestum'') is one of the smaller

species In biology, a species is the basic unit of Taxonomy (biology), classification and a taxonomic rank of an organism, as well as a unit of biodiversity. A species is often defined as the largest group of organisms in which any two individuals of ...

horned lizard Horned lizards (''Phrynosoma''), also known as horny toads or horntoads, are a genus of North American lizards and the type genus of the family Phrynosomatidae. The common names refer directly to their horns or to their flattened, rounded bodies, ...

. Their specific epithet is from the

Latin Latin (, or , ) is a classical language belonging to the Italic branch of the Indo-European languages. Latin was originally a dialect spoken in the lower Tiber area (then known as Latium) around present-day Rome, but through the power ...

word ''modestum'', meaning modest or calm. They are found in the

United States The United States of America (U.S.A. or USA), commonly known as the United States (U.S. or US) or America, is a country primarily located in North America. It consists of 50 U.S. state, states, a Washington, D.C., federal district, five ma ...

, in western

Texas Texas (, ; Spanish language, Spanish: ''Texas'', ''Tejas'') is a state in the South Central United States, South Central region of the United States. At 268,596 square miles (695,662 km2), and with more than 29.1 million residents in 2 ...

New Mexico ) , population_demonym = New Mexican ( es, Neomexicano, Neomejicano, Nuevo Mexicano) , seat = Santa Fe, New Mexico, Santa Fe , LargestCity = Albuquerque, New Mexico, Albuquerque , LargestMetro = Albuquerque metropolitan area, Tiguex , Offi ...

eastern

Arizona Arizona ( ; nv, Hoozdo Hahoodzo ; ood, Alĭ ṣonak ) is a U.S. state, state in the Southwestern United States. It is the list of U.S. states and territories by area, 6th largest and the list of U.S. states and territories by population, 14 ...

, southeastern

Colorado Colorado (, other variants) is a state in the Mountain states, Mountain West subregion of the Western United States. It encompasses most of the Southern Rocky Mountains, as well as the northeastern portion of the Colorado Plateau and the wes ...

and eight states in northcentral

Mexico Mexico ( Spanish: México), officially the United Mexican States, is a country in the southern portion of North America. It is bordered to the north by the United States; to the south and west by the Pacific Ocean; to the southeast by Guate ...

where they are referred to as "''tapayaxtin''".

Habitat

Roundtail horned lizards prefer rocky and sandy, semiarid habitat with sparse vegetation, near

harvester ant Harvester ant, also known as harvesting ant, is a common name for any of the species or genera of ants that collect seeds (called seed predation), or mushrooms as in the case of '' Euprenolepis procera'', which are stored in the nest in commun ...

or especially

honeypot ant Honeypot ants, also called honey ants, are ants which have specialised workers (repletes, plerergates, or rotunds) that are gorged with food to the point that their abdomens swell enormously. Other ants then extract nourishment from them, throug ...

colonies, which is their primary

diet Diet may refer to: Food * Diet (nutrition), the sum of the food consumed by an organism or group * Dieting, the deliberate selection of food to control body weight or nutrient intake ** Diet food, foods that aid in creating a diet for weight loss ...

Description

The color of roundtail horned lizards usually reflects the color of the soil in their native habitat. Most are uniformly

grey Grey (more common in British English) or gray (more common in American English) is an intermediate color between black and white. It is a neutral or achromatic color, meaning literally that it is "without color", because it can be compos ...

in color, but they can also be light

brown Brown is a color. It can be considered a composite color, but it is mainly a darker shade of orange. In the CMYK color model used in printing or painting, brown is usually made by combining the colors orange and black. In the RGB color model use ...

, or even a pale

yellow Yellow is the color between green and orange on the spectrum of light. It is evoked by light with a dominant wavelength of roughly 575585 nm. It is a primary color in subtractive color systems, used in painting or color printing. In ...

. Often, darker-colored regions occur around the neck and groin, and sometimes striping on the tail. They are short, flat, round-bodied lizards with short limbs, and small heads, which have a distinctive crest of nearly equal-length horns. Unlike other horned lizards, they lack a fringe of lateral scales and do not seek to flatten themselves to the ground to eliminate shadow; instead, they hunch their bodies into the shape of a rock for

camouflage Camouflage is the use of any combination of materials, coloration, or illumination for concealment, either by making animals or objects hard to see, or by disguising them as something else. Examples include the leopard's spotted coat, the b ...

, boldly casting a shadow. Their maximum size is 7 cm (2.7 in) snout-to-vent length, and 10.5 cm (4.3 in) total length. Smith, H.M. and E.D. Brodie, Jr. (1982). ''Reptiles of North America, A Guide to Field Identification''. Golden Press. New York. pp. 126–127. Phrynosoma_modestum2

Reproduction

Roundtail horned lizards are

oviparous Oviparous animals are animals that lay their eggs, with little or no other embryonic development within the mother. This is the reproductive method of most fish, amphibians, most reptiles, and all pterosaurs, dinosaurs (including birds), a ...

, breeding and laying

eggs Humans and human ancestors have scavenged and eaten animal eggs for millions of years. Humans in Southeast Asia had domesticated chickens and harvested their eggs for food by 1,500 BCE. The most widely consumed eggs are those of fowl, especial ...

in early summer.

References

Bibliography

*Hammerson, Geoffrey A. ''Amphibians and Reptiles in Colorado''. 2nd edition.

External links

Herps of Texas: ''Phrynosoma modestum''Horned Lizard Conservation Society
{{Authority control Phrynosoma Reptiles of Mexico Reptiles of the United States Fauna of the Southwestern United States Reptiles described in 1852