Image of Neognathophausia ingens (Dohrn 1870)

Description:

Mysids and Lophogastrids are "opossum shrimps" because the females carry their eggs and young in a thoracic pouch or "marsupium". The dorsal wall of the pouch is the ventral surface of the thorax, while the ventral wall is composed of "oostegites", which are inner, plate-like processes (endopods) projecting from the coxa of the thoracic legs of mature females. The processes overlap one another, forming the pouch. In this 15 cm female with young, the pouch can be clearly seen. She is live and swimming with her pleopods. Photo by Dave Cowles