The Tapeworm Spiniloculus-Mavensis (Tetraphyllidea, Onchobothriidae) From the Brownbanded Bambooshark in Australia

Abstract

Sixteen specimens of the tapeworm Spiniloculus mavensis were collected from the spiral valve of the brownbanded bambooshark in Australia. These specimens were examined with both light and scanning electron microscopy (SEM) and were compared with specimens of Acanthobothrium lineatum. The scolices of 50% of the specimens of S. mavensis were spined. The concept of a loculus is discussed; it was determined that each of the bothridia of S. mavensis possesses three loculi distinguished by two types of costae. The anterior costa is composed of radial muscle fibres similar to the costae in other onchobothriids such as A. lineatum; the posterior costa consists of transverse muscle fibres with little external representation and is therefore difficult to see with SEM. It is suggested that this construction accounts for the disagreement among previous authors with respect to the number of post-hook loculi. The specific description of S. mavensis is supplemented and the description of Spiniloculus is emended.