What is the average weight of a pterodactyl?

The Word pterodactyl is a term applied to a number of different flying reptiles. Some 5 dozen different kinds have been recorded, and they range in size from that of a small bird to the really big ones with 40 foot wingspans. They didn't weigh much, though. Remember that they had to fly. The weight of the heaviest of the flying reptiles, those really big ones, was less than 100 pounds.