Flora of North America says the "antherodes yellow sometimes with central maroon spot". The key here is SOMETIMES, not always. One important key that can't be seen in the any of the photos is the spathes. If that were visible it would be easy to be sure because there are only three species is North America that have distinct bases, C. communis, C. caroliniana and C. diffusa.
Since it is not possible we have to look at other clues.
The photo one shows distinctive dark green stripes on the spathe which is indicative of C. communis, so ID is probably correct.
Photo two shows no distinct stripes on spathe plus it has a larger proximal petal that is nearly the same color as the distal petals so not likely C. communis. It looks to me more like C. virginica. piksihk who contributed the photo lives in a county where C. virginica grows so that would be my best guess without actually having the plant in hand.
Photo three and four, I have no guess. Other than the lack of maroon spot there is not enough visible to make any guess.
Photo five, JonnaSudenius is not in North America, but the fact that it has three equal size large blue petals indicates that it is not C. communis which has a very reduce proximal petal that is lighter than the distal petals. This is the quote from FNA for C. communis, " proximal petal paler or white, very reduced, distal petals blue to bluish purple".
