Saccogaster, Alcock, 1889

Van Hinsbergh, Victor W. M. & Helwerda, Renate A., 2019, Fish Otoliths from the Cabarruyan Piacenzian-Gelasian fauna found in the Philippines, Zootaxa 4563 (3), pp. 401-443 : 422-423

Saccogaster sp.

(Figures 72–73)

Material: 3 specimens in total. Anda1 (1) RGM 962240; Anda2 (1) RGM 962241 ; Anda4 (1) RGM 962242 .

One adult, one juvenile, and one eroded otolith are available. The adult specimen has an elliptical to fusiform shape (OL:OH=2.00), while the younger one has a regular oval shape (OL:OH=1.72). In the adult specimen the dorsal rim has very obtuse pre- and postdorsal angles, while the ventral rim is regularly rounded; the posterior part is slightly protruded. The rims are smooth. The inner and outer surfaces are convex. A small centrally localized oval sulcus is oriented with its length axis along the length axis of the otoliths; it is covered by a single elevated colliculum. The sulcus is connected to the anterior tip of the otoliths by a collicular crest. A slight dorsal depression is visible, while the ventral field is convex. The outer surface is smooth and particularly in dorsoventral direction strongly convex. The transition from outer to inner side is sharp. The inner side is slightly convex, almost flat.

The outline and particular shape, size, and orientation of the sulcus are characteristic for the genera Cataetyx , Grammonus and Saccogaster . The equal-sized dorsal and ventral fields, the sulcus and the thin ridge between the sulcus and anterior point identify the specimens as Saccogaster , but on the basis of the two specimens a species identification seems premature to us.

PLATE 7