Tim Fitzharris / Vervain (Verbena officinalis) at Franklin Mountains State Park, Chihuahuan Desert, Texas

Jack Dykinga / Aerial view of Urique Canyon after summer monsoonal rain, Barranca Del Cobre NP, Chihuahua, Mexico

Tim Fitzharris / Opuntia (Opuntia sp) in Chihuahuan Desert landscape, Big Bend National Park, Texas

Tim Fitzharris / Agave (Agave sp) plants and Chisos Mountains seen from Chisos Basin, Big Bend National Park, Chihuahuan Desert, Texas

Tim Fitzharris / Cloud over White Sands National Park, Chihuahuan Desert, New Mexico

Michael & Patricia Fogden / Southern Grasshopper Mouse (Onychomys torridus) male singing on its territory, Chihuahua Desert, Mexico

Mitsuaki Iwago / Chihuahua (Canis familiaris) two puppies nuzzling

Lynn M. Stone / Chihuahua with Rhododendron leaves in background. Haddam, Connecticut, USA. May.

Mark Raycroft / Chihuahua (Canis familiaris) parent with puppy, North America

Mark Raycroft / Chihuahua (Canis familiaris) puppies, North America

Mark Raycroft / Chihuahua (Canis familiaris) puppy, North America

Mark Taylor / Chocolate-and-tan Chihuahua standing.