The plainfin grenadier (Ventrifossa divergens) is a species of rattail.

This is a deep-water fish found at depths of up to 772 m.[citation needed] It has a wide distribution in the Indian and western Pacific Oceans.

[1] This species reaches a length of 30 cm.

[citation needed] As suggested by the common name, it has a uniformly dark first dorsal fin, lacking the contrasting blotch seen in many species in the genus.

It also has a black margin to its snout.