 "Mastigopsis hjorti" is similar to "Idioteuthis cordiformis" in that it has large fins, skin tubercles, no pocket between the bridles and the large dividing, protective membranes on the tentacular clubs but the main difference is that this species has photophores on its eyes.The suckers on the tentacular club are all of similar size, except for those nearest the tip.The funnel has a locking-apparatus which has an oval, slightly curved depression and towards the posterior its sides protrude having no cartilaginous fleshy projections.