mola • Phylum: Chordata • Subphylum: Vertebrata • Class: • Division: Teleostei • : (, boxfish, porcupine , pufferfish) • : • , : Mola mola

Teleost and Tetradontiformes

• Division Teleostei – the most dominant living – account for 96% of all living fishes

http://www.amonline.net.au/fishes/fishfacts/fish/mola.htm • Order Tetradontiformes – the most highly derived fishes – “The pinnacle of teleostean evolution” • World’s heaviest bony fish – Characterized by a high degree of fusion or loss of numerous in the head and body • Can grow to be 2m long and weigh as much as 1000kg (2200 pounds) – Date back to the early Eocene (55 to 38 million years ago) • The largest mola ever recorded was 2235 kg (4,927 lbs). • It measured 3.1 m (10 ft) from snout tip to "tail" fin and 4.26 m (14 ft) from to anal fin tip

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http://w w w .groton.k12.ct.us/WWW/fsr/student/spr04/Jessi/FISH.htm • They lack true teeth and instead have tooth plates • Molas have a large number of cartilaginous elements or that are shaped like a beak -lined bones in their skulls and in their fin supports. • Mola mola comes from the latin word “millstone” • The body is essentially rectangular in side view with very • Their aptly named “sunfish” because they are usually tall, thin dorsal and anal fins that propel the fish found basking on their sides at the surface • They lack a true tail but have a “pseudocaudal” tail fin made up primarily of dorsal and anal fin rays

Reproduction Mola diets • Spawning habits • Mostly pelagic feeders unknown • Capable of producing • Diet consists of , Portuguese man-o- 300 million , an war, ctenophores and . apparent record among • , sponges, serpent star bits, grass, fishes , small fishes and deepwater eel • After hatching, the larvae have also been found in M. mola guts larvae look more like pufferfish. They • Indicating that they forage both at the measure just 2.5 mm surface, among floating weeds, on the • As they grow the seafloor and into deep water spines disappear, as do their tails

http://www.oceansunfish.org/lifehistory.html

2 Molas and parasites Parasites cont’d • Molas are infamous for their impressive • Molas have been seen parasite load frequenting kelp beds • Up to 40 genera as well as other have been found on cleaning stations one individual • Could bask on side to let gulls remove parasites

http://www.amonline.net.au/fishes/fishfacts/images/mmolapar.jpg&imgrefurl

Molidae evolution Predators

• Large portion of in Pacific • Market in Asian culture • Highly derived group – The most advanced tetraodontiforms are the three species of temperate • Sea lions and tropical molas (Molidae) • Orcas • Molidae has returned anatomically to a starting point in fish evolution • Parasites • It is therefore important to bring up that evolution does not mean moving from primitive to advanced forms

3 The Diversity of Fishes, Helfman G.S., B.B. Collette, and D.E. Facey, Massachusetts, Blackwell Science, Inc. 1999 http://www.oceansunfish.org/lifehistory.html

“The mola’s rediscovery of the utility of cartilage underscores the observation that all living fishes are the successful result of the trial and error processes of mutation and natural selection”

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