Placoid scales are present in :
(a) Hippocampus
(b) Scoliodon
(c) Labeo
(d) Protopterus
Answers
A fish scale is a small rigid plate that grows out of the skin of a fish. The skin of ... The placoid scales of cartilaginous fishes are also called dermal denticles and are structurally ...
Answer:
Placoid scales are present in Scoliodon fish.
Explanation:
Placoid Scales:
Placoid scales (or denticles) are spiny, toothlike projections seen only in cartilaginous fishes. Ganoid scales, sometimes considered a modification of the placoid type, are chiefly bony but are covered with an enamel-like substance called ganoin.
Scoliodon has an elongated, spindle-shaped body tapered at the ends, making it a very fast swimmer. The trunk and tail are laterally compressed, while the head region is dorsoventrally compressed. The entire body is covered by an exoskeleton of placoid scales.