Welcome Doc,

This link http://home.xnet.com/~eo/word.html which I posted recently under forum Weekly Themes, thread "This week's theme: yours to discover" has this to say:

The shortest word with the vowels in alphabetical order is CAESIOUS (light blue), with eight letters. Slightly longer such words are ACHEILOUS, ACHEIROUS, AEROBIOUS, ARSENIOUS, ARTERIOUS, AUTECIOUS, and FACETIOUS. Pierre Abbat says ACEITOU (Portuguese for past tense of to accept) and ALEIJOU (Portuguese for past tense of paralyze) are the shortest words he knows in any language written in the Roman alphabet which have all five vowels in order. PANCREATICODUODENOSTOMY is the longest word with all six vowels in order.

whilst from http://alabanza.com/kabacoff/Inter-Links/fun/puzzles/language we get:
shortest [word with] vowels in reverse order muroidea
longest [word with] vowels in reverse order subcontinental