Shelley the Turtle appeared on Sesame Street primarily during the late 80s and early 90s. Shelley was a friendly but slow turtle.
His most recent apparance, with the same voice but referred to in the dialogue only as "The Turtle," occurred in Season 30, and involved his attempts to join the menagerie on Old MacDonald's farm. [cite]
The puppet later appeared with a new shell as Seymour.