This Early Miocene sunfish, Austromola angerhoferi, is estimated to have a total length of 3.2 meters (10’6”), making it the largest known Cenozoic teleost fossil. Mola mola can get somewhat larger — 3.33 m — although considering Austromola is know from only three specimens (the others being 1.5–1.7 and 2.4 m), I’d imagine it was considerably larger on average. Austromola is essentially “modern” in shape, although with some minor plesiomorphic traits (more vertebrae, hexagonal scales).
Gregorova, R. et al. (2009) A giant Early Miocene sunfish from the North Alpine Foreland Basin (Austria) and its implication for molid phylogeny. Journal of Vertebrate Paleontology 29(2) 359–371.
The earliest illustration of Sunfish, presumably Mola mola, from A) Rondelet in 1554 and B) Gesner in 1558. Considering this is from the era of terrible walruses, the fact that they’re at all recognizable is pretty amazing.
Johnson, G. & Britz, R. (2005) Leis’ Conundrum: Homology of the Clavus of the Ocean Sunfishes. 2. Ontogeny of the Median Fins and Axial Skeleton of Ranzania laevis (Teleostei, Tetraodontiformes, Molidae). Journal of Morphology 266 11–21.
Pumpkinseed Sunfish (Lepomis gibbosus)
The pumpkinseed is the most widely distributed and abundant sunfish in the eastern United States. They seem to prefer weedy, warm-water lakes and ponds, using weed patches, docks, and logs for cover and usually staying close to shore. They are present in the calm pools of most rivers. The average pumpkinseed is about 5 - 6 inches in length, although some may approach 10 inches.
(via: Cornell Univ.)