Robert Ivens:
Arizona Gray Squirrel (Sciurus arizonensis)
Robert Ivens:
Common Chuckwalla (Sauromalus ater)
Robert Ivens:
Common Chuckwalla (Sauromalus ater)
Robert Ivens:
Common Chuckwalla (Sauromalus ater)
Robert Ivens:
Black-throated Sparrows (Amphispiza bilineata)
Robert Ivens:
Black-throated Sparrows (Amphispiza bilineata)
Robert Ivens:
Black-throated Sparrow (Amphispiza bilineata)
Robert Ivens:
Black-throated Sparrow (Amphispiza bilineata)
Robert Ivens:
Sonoran Horned Lizard (Phrynosoma goodei)
Robert Ivens:
Curve-billed Thrasher (Toxostoma curvirostre)
Robert Ivens:
Curve-billed Thrasher (Toxostoma curvirostre)
Robert Ivens:
Sidewinder (Crotalus cerastes)
Robert Ivens:
Harris' Antelope Squirrel (Ammospermophilus harrisii)
Robert Ivens:
Western Diamond-backed Rattlesnake (Crotalus atrox)
Robert Ivens:
Sierra Madre Dancer (Argia lacrimans)
Robert Ivens:
Sierra Madre Dancers (Argia lacrimans)
Robert Ivens:
Rock Wren (Salpinctes obsoletus)
Robert Ivens:
Black-tailed Gnatcatcher (Polioptila melanura)
Robert Ivens:
Arizona Snaketail (Ophiogomphus arizonicus)
Robert Ivens:
Arizona Black Rattlesnake (Crotalus cerberus)
Robert Ivens:
Arizona Black Rattlesnake (Crotalus cerberus)
Robert Ivens:
Two-tailed Swallowtails (Papilio multicaudata)
Robert Ivens:
Two-tailed Swallowtails (Papilio multicaudata)
Robert Ivens:
Wasps
Robert Ivens:
Apache Spiketails (Cordulegaster diadema)
Robert Ivens:
Riffle Darner (Oplonaeschna armata)
Robert Ivens:
Sonoran Desert Toads (Incilius alvarius)
Robert Ivens:
Juniper Hairstreak (Callophrys gryneus)
Robert Ivens:
Baja Bluet (Enallagma eiseni)
Robert Ivens:
Variable Dancer (Argia fumipennis)
