The albacore's pectoral fins can be longer than 30% of the fish's total length.

Date 1828-1849.
Source http://www.flickr.com/photos/biodivlibrary/10438834583
Author Buffon, Georges Louis Leclerc; Cuvier, Georges; Valenciennes
Full title Histoire naturelle des poissons / par m. le bon Cuvier ... et par M. Valenciennes.
Source: https://commons.wikimedia.org/wiki/File:Histoire_naturelle_des_poissons_(10438834583).jpg

The albacore (Thunnus alalunga), known also as the bonito or longfin tuna, is a species of tuna of the order Perciformes. It is found in temperate and tropical waters across the globe in the epipelagic and mesopelagic zones. There are six distinct stocks known globally in the Atlantic, Pacific, and Indian oceans, as well as the Mediterranean Sea. The albacore has an elongate, fusiform body with a conical snout, large eyes, and remarkably long pectoral fins. Its body is a deep blue dorsally and shades of silvery white ventrally. Individuals can reach up to 1.4 m in length. Order: Perciformes, Family: Scombridae, Genus: Thunnus, Species: Thunnus alalunga (Bonnaterre, 1788).
Synonyms:
Thunnus germo (Lacepède, 1801)
Scomber alalunga Bonnaterre, 1788