Creature type (Dungeons & Dragons) all animal type monsters are based on real world animals. Creature entries based on mythological, fictional, or nonexistent animals are usually classified as magical beasts (see below). Besides ordinary fish, birds, reptiles and mammals, the animal type is also applied to depictions of dinosaurs, prehistoric animals, and "dire" or specially modified, often larger and scarier, versions of real world animals. Some real world animals are not given the animal type in the game. Examples include arthropods (insects, spiders, etc.) and worms, which the game classifies as "vermin" (see below) and not animals. Mollusks, such as octopuses, are often classified as
Mummichog morphological differences. and genomic Further, eggs of the northern subspecies have filaments (adhesive chorionic fibrils) that eggs of the southern subspecies lack. While the northern subspecies deposits eggs in the sand, the southern subspecies often deposits eggs inside empty mussel shells. The mummichog is very similar to the banded killifish, "Fundulus diaphanus", and indeed the two species have been known to interbreed. The two species may overlap in their choice of habitat, but in general the banded killifish is more commonly found in freshwater, which is not the case for the mummichog. The banded killifish tends to have thin dark