[3][4] This species may be a senior synonym to Grimpoteuthis wuelkeri (but has fewer suckers), but the poor condition of the only known specimen (the holotype) hinders comparison.

[4] Grimpoteuthis plena, along with G. wuelkeri and G. discoveryi, may all be junior synonyms of G. umbellata, but this also cannot be resolved given the poor condition of the only known G. umbellata specimen.

[5] Grimpoteuthis plena was found in the northwestern Atlantic Ocean, at 1,963 meters deep.

[5] Specifically, the single known specimen of G. plena was collected at a latitude of 37º 35’N and a longitude of 71º 18’W in the northwestern Atlantic Ocean, with other species of the same genus being found nearby.

[4] The single G. plena specimen was found in the year 1880 by Verrill.