Robledo Mountains - Flickr - aspidoscelis (8)

The Robledo Mountains are a

mountain range A mountain range or hill range is a series of mountains or hills arranged in a line and connected by high ground. A mountain system or mountain belt is a group of mountain ranges with similarity in form, structure, and alignment that have arise ...

Doña Ana County, New Mexico Doña Ana County is located in the southern part of the State of New Mexico, United States. As of the 2020 U.S. Census, its population was 219,561, which makes it the second-most populated county in New Mexico. Its county seat is Las Cruces, t ...

just northwest of Las Cruces. They are an uplifted block of

Paleozoic The Paleozoic (or Palaeozoic) Era is the earliest of three geologic eras of the Phanerozoic Eon. The name ''Paleozoic'' ( ;) was coined by the British geologist Adam Sedgwick in 1838 by combining the Greek words ''palaiós'' (, "old") and ' ...

rocks on the west side of the

Rio Grande Rift The Rio Grande rift is a north-trending continental rift zone. It separates the Colorado Plateau in the west from the interior of the North American craton on the east. The rift extends from central Colorado in the north to the state of Chihuahu ...

. The range was named for Pedro Robledo, who died on May 21, 1598 and was buried nearby. Robledo was the first casualty of the Oñate expedition, sent to colonize the upper Rio Grande valley. A native of

Toledo, Spain Toledo ( , ) is a city and municipality of Spain, capital of the province of Toledo and the ''de jure'' seat of the government and parliament of the autonomous community of Castilla–La Mancha. Toledo was declared a World Heritage Site by UNESC ...

, Robledo was accompanied on the expedition by his wife and five children. These mountains are home to Early Permian trackways of

invertebrates Invertebrates are a paraphyletic group of animals that neither possess nor develop a vertebral column (commonly known as a ''backbone'' or ''spine''), derived from the notochord. This is a grouping including all animals apart from the chordat ...

and

vertebrates Vertebrates () comprise all animal taxa within the subphylum Vertebrata () (chordates with backbones), including all mammals, birds, reptiles, amphibians, and fish. Vertebrates represent the overwhelming majority of the phylum Chordata, with c ...

. In 2009, the main locality was designated the 100th ''active'' national monument 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 states, a federal district, five major unincorporated territori ...

, and named

Prehistoric Trackways National Monument Prehistoric Trackways National Monument is a national monument in the Robledo Mountains of Doña Ana County, New Mexico, United States, near the city of Las Cruces. The monument's Paleozoic Era fossils are on of land administered by the Bur ...

. Rock outcrops in the area preserve numerous examples of early

Permian The Permian ( ) is a geologic period and System (stratigraphy), stratigraphic system which spans 47 million years from the end of the Carboniferous Period million years ago (Mya), to the beginning of the Triassic Period 251.9 Mya. It is the last ...

trackways. These trackways include prints of '' Dimetrodon'', ''

Edaphosaurus ''Edaphosaurus'' (, meaning "pavement lizard" for dense clusters of teeth) is a genus of extinct edaphosaurid synapsids that lived in what is now North America and Europe around 303.4 to 272.5 million years ago, during the Late Carboniferous to ...

'', ''

Eryops ''Eryops'' (; from Greek , , 'drawn-out' + , , 'face', because most of its skull was in front of its eyes) is a genus of extinct, amphibious temnospondyls. It contains the single species , the fossils of which are found mainly in early Permian (a ...

'', ''

Cacops ''Cacops'' ("ugly look" for its strange appearance), is a genus of dissorophid temnospondyls from the Kungurian stage of the early Permian of the United States. ''Cacops'' is one of the few olsoniforms (dissorophids and the larger trematopids) ...

'' and many other small

pelycosaurs Pelycosaur ( ) is an older term for basal or primitive Late Paleozoic synapsids, excluding the therapsids and their descendants. Previously, the term ''mammal-like reptile'' had been used, and pelycosaur was considered an order, but this is now ...

Wilderness

Established in 2019 by the U.S. Congress, the Robledo Mountains Wilderness protects this ecologically diverse portion of the

Chihuahuan Desert The Chihuahuan Desert ( es, Desierto de Chihuahua, ) is a desert ecoregion designation covering parts of northern Mexico and the southwestern United States. It occupies much of far West Texas, the middle to lower Rio Grande Valley and the lo ...

in New Mexico. The 16,776 acre desert

wilderness area Wilderness or wildlands (usually in the plural), are natural environments on Earth that have not been significantly modified by human activity or any nonurbanized land not under extensive agricultural cultivation. The term has traditionally re ...

contains an assortment of canyons, cliffs, caves, and creeks and is managed by the U.S. Bureau of Land Management.Robledo Mountains Wilderness
- Wilderness Connect

References

External links

Las Cruces District Office
- BLM Mountain ranges of Doña Ana County, New Mexico Mountain ranges of New Mexico Organ Mountains–Desert Peaks National Monument Wilderness areas of New Mexico {{NewMexico-geo-stub