Around 800 possible genetic attributes (fin shape, body color, size, etc.) are available, which can be selectively shaped into virtually infinite numbers of unique fish.

However, these species differ in premaxillary dentition, juvenile and adult coloration, and adult maxillary barbel length and caudal fin shape.

Due to genomic recombination, F1 hybrids often display novel and bizarre fin shapes.

The caudal fin shape is variable, from slightly forked through, emarginate, truncate, or even slightly rounded, but not deeply forked.

Eight major fin shapes can be distinguished among the Decapodiformes: sagittate (the most common shape in squid), rhomboid, circular/elliptical, lanceolate, ear-shaped, ribbed, lobate, and skirt-like.

It differs from P. albilabris in having a taller dorsal fin and larger eye; it differs from P. butleri in having a shorter dorsal fin and shorter nasal barbels, a rounded pectoral fin shape, fewer procurrent caudal fin rays, and fewer gill rakers.

The full adult color pattern and fin shapes appear by at least 20 cm (8 in).

Caudal fin shapes vary considerably between shark species, due to their evolution in separate environments.

Concertgoers typically respond to the chorus line of "fins to the left, fins to the right" by extending their arms above their heads in a fin shape and moving them from left to right.