I have a lot of monarch caterpillars with 4 “spikes”, two front and back. I also have a few caterpillars with an extra set of spikes on the body. Are these monarchs too?
Bill in South Texas
The caterpillar in your photo is another member in the “Royal” Milkweed Butterfly genus that includes the Monarch. Your caterpillar belongs to the Queen, Danaus gilippus. There is one subspecies in Florida and the Mexican subspecies known as the Mexican Queen, Danaus gilippus strigosus, ignores the international border and strays north into Texas, New Mexico, Arizona and California. Unlike the Monarch, the Queen does not migrate.