Vokes, H. E., 1938. Upper Miocene Mollusca from Springvale, Trinidad, British West Indies. American Museum Novitates, 988.
        
            New Species-Group Names:
            
                - 
                    couvaensis Vokes, 1938. pl. 18. f. 16. 
                
                 
                - 
                    maga Vokes, 1938. pl. 19. f. 17. 
                
                 
                - 
                    medialira Vokes, 1938. p. 18. f. 18.