Plate 4

Plate 5

Lethrinus opercularis Valenciennes in Cuvier & Valenciennes, 1830: 289, Trincomalee, (Ceylon).
Lethrinus croceopterus Valenciennes in Cuvier & Valenciennes, 1830; 302, Seychelles.
Lethrinus argenteus Valenciennes in Cuvier & Valenciennes, 1830: 303, Seychelles.
Lethrinus leutjanus (not of Lacepède); Bleeker, 1850: 14, Sibogha, Sumatra; 1876-77: 120, pl. 354, East Indies.
Lethrinus nebulosus (not of Forsskål); Weber & Beaufort, 1936; 453, Indo-Australian Archipel.

Specimens examined.

Svntypes. —MNHN9057 (2 individuals: 144 and 197mm standard length) from Trincomalee, Ceylon.
Holotype of L. croceopterus. —MNHN9066 (126) from Seychelles.
Lectotype of L. argenteus. —MNHN9061 (1 of 2: 157) from Seychelles, here designated.
BMNH1927. 4. 14. 39 (173), MNHN9063 (3: 111, 117, 126) from Seychelles.

D. X, 9; A. III, 8; P₁. 13; P₂. I, 5; C. 8 + 7; L. lat. 47 to 48; Ltr. 6 or 7/i/14 or 15.

Proportional measurements of some specimens are shown in Table 10.

Head length less than body depth. End of jaws on the vertical through anterior nostril. Interorbital area slightly convex. Third or fourth dorsal spine longest. 6 scale rows between lateral line and median dorsal spines. Inner base of pectoral densely covered with scales. Lateral teeth of jaws include strong molars in adults.

Color. —Olive-green above, paler below. Bright red spot on posterior end of operculum. A few dark streaks sometimes from eye forward. Individual scales on the back sometimes with white center. Fins yellow to red.

Distribution. —Seychelles to East Indies.

Remarks. —The present species resembles L. lentjan in many characteristics and seems to be closely related to it. L. opercularis is different from L. lentjan mainly in having scales which cover the inner base of the pectoral densely and in lacking the red spot on its outer base of the pectoral, which can be observed in L. lentjan. The relationship of these two species should be studied better in the future.

The two specimens in Paris labeled as the type of L. argenteus (MNHN9061) belong to different species from each other. The smaller (157mm standard length) agrees better with the original description and is here designated as the lectotype.