The Crimson-collared Grosbeak is primarily found in northeastern Mexico from central Nuevo León and central Tamaulipas south to northern Veracruz; however, it occasionally strays into the Rio Grande Valley of southern Texas, mostly in winter.
Mature males have black plumage with a dull red (Sibley 2000) or pinkish red (Howell and Webb 1995) "collar" on the nape, shoulders, and belly (much like the Crimson-collared Tanager); the belly is mottled with black. Mature females have a black head and breast like males but greenish upperparts and yellowish underparts. Young birds are similar to females but have less black. The beak is black, big and stubby, with the upper mandible jutting roughly perpendicular to the forehead.
The song is a warble, often slurred upward at the end. Calls are penetrating whistles starting with an "s" sound, slurred downward or one upward followed by one downward.
- Steve N. G. Howell and Sophie Webb (1995). A Guide to the Birds of Mexico and Northern Central America. Oxford University Press. ISBN 0-19-854012-4.
- Sibley, David Allen (2000). The Sibley Guide to Birds. Alfred Knopf. p. 534. ISBN 0-679-45122-6.