Pomadasys kaakan ( Cuvier, 1830 )

Lin, Chien-Hsiang, Li, Kuang-Ti & Chang, Chih-Wei, 2013, Identification Of Pomadasys Species (Pisces, Haemulidae) From An Archaeological Midden Site In Nankuanli East (Taiwan), Based On Otolith Morphology, Raffles Bulletin of Zoology 61 (1), pp. 293-302 : 297

Pomadasys kaakan ( Cuvier, 1830)

( Fig. 3b ; no. 3–4 in pl. 1)

Material examined. — 13 sagittae ( NMMBOL 1952, 3796–3805, 3919–3920).

Description. — Shape oval, with convex medial face and slightly concave lateral face due to moderate thickness of central portion. Dorsal margin subangular and ventral margin round. Crista superior moderately developed along the ostium, ridge-like anterior and well-developed posterior to caudal flexion. Dorsal trough visible to crista superior. Crista inferior moderately developed along ostium, well developed along cauda. Ostium elongate with rounded posteroventral corner. Cauda flexion approximately halfway along its length, but curvature smooth (not angled). Excisura moderately wide, pointing anteriorly, without notch. Smaller samples of OL <8 mm (NMMBOL 3801, 3803, 3919, 3920) with shallow, very acute and pointing upwards excisural notch on dorsal margin near anterior ostium.

Dimensions. — OL, 5.91–10.42 mm; OH, 3.73–7.75 mm; OT, 1.30–3.14 mm; OsL, 2.47–4.59 mm; OsH, 1.17–2.10 mm.

Diagnosis. — The narrow ostium of this species is different from the deep ostium of P. quadrilineatus , and the position

of the caudal flexion (at its half) and its gentle curvature is distinct from P. argenteus . The otolith morphology of P. kaakan is very similar to that of P. argenteus , and a careful examination is necessary to differentiate the two. Most P. kaakan have an excisura without a notch, and even if they do, the excisural notch is very different from that of P. maculatus .

Figures

Fig. 3. Medial surfaces of the right sagittae of Pomadasys argenteus, NMMBOL00223 (a); P. kaakan, NMMBOL01952 (b); P. maculatus, NMMBOL00719 (c); P. quadrilineatus, NMMBOL00799 (d). Scale bar = 1 mm.