Pat, I am just not certain. But I do know that is isn't a specific temperature but a range of temperatures that are acceptable for spawning. Spawning will peak at a warmer temperature than the onset and by the time the crappie spawn peaks the LMB will be spawning to.
Here is link to the Google search "crappie spawning temperature" Here is link to the google search "largemouth bass spawning temperature" You will notice in surfing these links that there is variability in what people think is the range of temperatures but they are also very similar in terms of the range and expected peaks of spawning for both species. One reference state the LMB peak is between 64F and 68F. Another reference states that the Crappie peak is 68F to 72F which is just the opposite of what I thought (like you that Crappie peak before).
To be sure, I really don't know. This much I do know,both LMB and Crappie are adapted to spawn earlier than other species in order to exploit the prey fry that follow their own fry emergence. Their spawning temperature ranges are also very similar.
