Is iced tea spoon same measure as tea spoon?

Iced tea spoons in most flatware patterns have smaller bowls than that same pattern's tea spoons.

Further, neither an iced tea spoon nor a tea spoon is a teaspoon measure, nor are they intended to be. If you need a teaspoon (as in a recipe), that means to use a measuring spoon, not a piece of arbitrarily-sized flatware.