About Calosoma macrum LeConte, 1853
Calosoma macrum, commonly called the long caterpillar hunter, is a species of ground beetle that belongs to the subfamily Carabinae. This species was first described by John Lawrence LeConte in 1853. It can be found in the Mexican states of Coahuila and Tamaulipas, and in the United States in Arizona, Louisiana, New Mexico, Oklahoma, and Texas. In these regions, it lives in open areas at mid-altitude. Adult individuals of Calosoma macrum measure between 24 and 30 millimetres (0.94 to 1.18 inches) in length, are solid black in color, and occur at elevations ranging from 1,000 to 1,600 metres (3,300 to 5,200 feet).
