Dictionary of Ichthyology  

Spreitzer vertebrae = a unique type of anterior caudal vertebrae in which the haemal arch is not closed; the open haemal arches of the first 2-3 caudal vertebrae allowing the expansion of the abdominal cavity posteriorly into the caudal peduncle, especially in adults with swollen gonads. Found in Ammocrypta (Percidae) and named for August Edward Spreitzer who was the first person to report on this type of vertebra (John C. Bruner, pers comm., 2004).

Spreitzer vertebrae (sprv), lateral and ventro-lateral views of Ammocrypta pellucida, drawing by, and courtesy of, John Clay Bruner (see Bruner (2004)).

Canadian Museum of Nature