How to Identify Blue cod

To identify Blue cod (Parapercis colias), look at these key features.

Physical Characteristics

Body shape

elongated

Coloration

Highly variable, often adapting to the local substrate. Dominant colors range from mottled blue-grey to greenish-brown on the dorsal surface, fading to lighter shades on the ventral side. Males tend to be more intensely colored, especially during breeding season, often displaying vibrant blue, green, and orange hues, particularly around the head and fins. Females and juveniles are typically duller, with more cryptic brown and grey patterns. Distinctive dark spots or blotches may be present along the flanks.

Scale type

ctenoid

Mouth position

terminal

Distinctive features

Large head with prominent eyes set high on the head., Robust, slightly compressed body., Large, fleshy lips., A single, long dorsal fin with both spiny and soft rays., Pectoral fins are large and fan-like., Caudal fin is truncate to slightly rounded., Lateral line is complete and prominent.

Dorsal fin

Single, long dorsal fin with 5-6 spines followed by 20-22 soft rays. The spiny and soft ray portions are continuous.

Tail fin

Truncate to slightly rounded caudal fin.

Pectoral fin

Large, fan-shaped pectoral fins with 15-17 rays.

Distinctive fins

Pelvic fins are jugular (positioned anterior to the pectoral fins) with 1 spine and 5 soft rays, often appearing thick and fleshy.

Identification Tips

1. 1

   Coloration

   Look for the mottled blue-grey to greenish-brown body, often with darker blotches. Males can exhibit striking blue, green, and orange patterns, especially on the head and fins.

2. 2

   Head and Mouth

   Note the large head, prominent eyes, and thick, fleshy lips. The mouth is terminal and relatively large.

3. 3

   Dorsal Fin

   Observe the single, continuous dorsal fin with both spiny and soft ray portions.

4. 4

   Pelvic Fins

   Identify the jugular pelvic fins, positioned forward of the pectoral fins, which are often thick and robust.

Explore Blue cod