The first special turtle release is known as the Halloween turtles – (see Whats a Halloween turtle?) and these were laid on 31st October 2009.
Since 2010 Special turtles have taken on more precedence as it is only through breeding these together that you have a chance for a Birthstone turtle. Specials discussed in other questions, in their order of appearance on the grid are – * Grand Opening (or Party Turtle) – September 2009 * Halloween Turtle – October 2009 * Crash Turtle — November 2009 * Anomaly Turtle (a Crash) -November 2009 * Gray Man Group Turtle – November 2009 * Winter Turtle – December – January 2010 * Holiday Turtle – December 22 – 29, 2009 * New Years Turtle – January 1st 2010 * Birthstone Turtles – Jan, Feb, March…