Then the men of Israel said to Gideon, Rule you over us, both you, and your son, and your son's son also; for you have saved us out of the hand of Midian.
"They had golden ear-rings because they were Ishmaelites"  (Judges 8:24).  All of those who were defeated by Gideon were also called, "Midianites," and here it is clear that they were also identifiable as "Ishmaelites."  This passage refutes the critical enemies of Genesis who allege "multiple sources," "contradictions," etc., in  Genesis 37:27-28, where the company of people to whom Joseph's brothers sold him are referred to in those verses both as "Ishmaelites," and as "Midianites."