Dmitri Borgmann, in "Vowel Patterns" in his book "Language on Vacation" (Scribner's, 1965), muses on the finding of what would be the 'ultimate triumph' a 5-letter word constructed from one each of the five vowels A, E, I, O, and U. If you turn to page 638 of "The Encyclopedia of Paleontology" (Dowden, Hutchinson& Ross, 1979), edited by Rhodes W. Fairbridge and David Jablonski, you will find IOUEA, the name of a Cretaceous fossil sponge genus!
"IOUEA: A Cretaceous Coup,"
Word Ways: Vol. 26
, Article 7.
Available at: http://digitalcommons.butler.edu/wordways/vol26/iss2/7