Diplodocus hallorum (Seismosaurus)
Mrs. Mama is a character in the Land Before Time series. She is a Diplodocus, which is called a "Longneck" in the films and television series. She first appears in The Land Before Time IX: Journey to Big Water, and is voiced by Miriam Flynn. "Mrs. Mama" is not her real name, but what Ducky referres to her as. In the credits, she is credited as "Diplodocus Mom".
When Ducky accidentally falls into her nest, and the others try to get her out, Mrs. Mama thinks that they are trying to hurt her eggs, and corners them against a rocky wall. However, when Ducky apologizes for disturbing the nest, and explaines what is happening, she realizes that they are just children, and softens toward them. She also lets them spend the night in her nest, as it is getting late and they need a safe place to sleep. During this time, her eggs hatch.
Mrs. Mama is shown to be very protective of her children, and to be hostile towards anything she thinks is a threat. However, she is very friendly and hospitable to those she can trust.