Adult Spotted Glistening Meadow Worms are about three inches long. Newborns are extremely short. They are light pink and have a darker shade of pink on their legs.
They tend to move like an inchworm. Sea snails are their enemies, like said snails and worms.
Newborns spit out a green secretion.
From the episode, Mrs. Wormsley was pregnant for approximately one 24-hour period. The worm would stay under something in order to ensure its young's safety. Its belly was stretched out only until its children's birth, which was the next day.
The adults make a nest out of what seems to be brown, dead seaweed. Under that seaweed is a small hole, with the size of the hole varying depending on the size of the adult. The nest easily breaks apart when large objects impact it.
Mrs. Wormsley is the most notable specimen of its species. She has five young children, who all look similar to each other.