Some Remarkable Pre-Historic Snakes

Earth suffered a miserably hot climate during the Paleocene Epoch (65 million-55 million years BP).  The average annual temperature, not the average high, but the average temperature in South America near the equator was 91 degrees F.  Rainfall totals were higher than they are today as well.  Just imagine the humidity of a 110 degree afternoon after a mid-day shower.  Humans and most modern species of mammals would find such conditions unbearable.  But it was a perfect environment for the titanic snake (Titanoboa cerregonensis).

The bones of 24 titanic snakes were found at the Cerrejon open pit coal mine, the largest strip mine in the world.  It’s located in Colombia, South America.  It’s the only fossil site on that continent, yielding vertebrate bones from the Paleocene Epoch.  

The titanic snake grew to 45 feet long and weighed 2500 pounds.  This replica is displayed at the University of Florida Museum of Natural History.  Note the crocodiliforme in its mouth.

Jon Bloch holding Titanoboa vertebrae compared to modern snake. Florida Museum photo by Jeff Gage.

Not only was the titanic snake long but it was massive.  In this photo its vertebrae is compared to that from an anaconda which reaches lengths of  17 feet.

The largest extant species of snake in the world today is the reticulated python (Python reticulatus) which reaches lengths of 23  feet.  The titanic snake was double the length and much more massive.  It too killed its prey using constriction.  It likely preyed upon crocodiliformes, primitive mammals, and ground nesting birds.  South American animal life from the Paleocene epoch is poorly known.  The Cerrejon coal mine is the only Paleocene vertebrate fossil site known on the entire South American continent.  The ribs and vertebrae (but no skulls so far) from at least 24 individual titanic snakes were found here along with remains of 7 foot long crocodiliformes (Cerrojenisuchus improcerus), and a 5 foot wide turtle (Puentomys mushaisaensis).  Crocodiliformes are an extinct family offshoot of the ancestors of modern crocodiles and alligators.  Scientists believe the wide rounded shell of the turtle species they found evolved as a defense mechanism against the titanic snake.  The shape would have made them difficult for the snake to swallow.  The titanic snake was probably the top predator in its environment.  The Paleocene began after the K-T impact annihilated all the non-avian dinosaurs.  Reptiles rapidly replaced ecological niches left vacant after the demise of the dinosaurs.

The titanic snake became extinct long before man evolved, but Australian aborigines did co-exist for a while with the rainbow serpent (Wonambi naracoortensis).  The rainbow serpent reached lengths of 18 feet and lived as an ambush predator of kangaroos when they went to drink at waterholes.  It constricted its prey to death.  The Wonambi is named after the rainbow serpent of Australian aborigine legend.  Supposedly, the rainbow serpent is what is visible when sunlight shines on water at an angle that produces shimmering lights from the color spectrum.  The rainbow serpent is regarded as the guardian of water holes.  Aborigines still will not let young children play near waterholes for fear of the snakes.  Scientists speculate the legend may be based on tribal memories of the Pleistocene species of Wonambi because, if the snake preyed upon kangaroos, it was surely capable of taking a small child.

Replica of the rainbow serpent.  It’s extinct, so the actual color pattern is unknown.

Reptiles were the top predators in Australia until man colonized the continent ~40,000 years ago.  Rainbow serpents along with Megalania, a 23 foot long monitor lizard, and Quinkana, a 21 foot long land crocodile, ruled the food chain. (See also https://markgelbart.wordpress.com/2010/03/31/the-real-dragon-of-the-pleistocene-megalania/) Overhunting by man drove almost all of Australia’s megafauna into extinction.  The giant predatory reptiles became extinct when giant kangaroos, 3 ton rhino-like wombats, marsupial lions, 150 pound echidnas, and ostrich-sized birds all disappeared within a few thousand years of man’s initial appearance.  Some scientists proposed that anthropogenic fires transformed the landscape and contributed to these extinctions, but the latest studies show these fires occured a century after the Australian megafauna became extinct.  These findings are consistent with studies of megafauna extinction in North America and Madagascar. The increase in pyrogenic habitat was likely a consequence of megaherbivore extinction.  After man killed much of the megafauna, flammable plant material accumulated to a greater degree than formerly.

Southeastern North America was home to a remarkable prehistoric snake–the Chocktaw giant sea snake (Pterosphenus schucherti).  It lived during the Eocene (55 million-33 million years BP) when the coastal plain of the south was  a shallow ocean.  Pterosphenus grew to 18 feet long, double the size of the largest species of modern sea snake.

Photo of a yellow sea snake (Hydrophis spiralis), the largest species of extant sea snake.  It grows to 9 feet long, half the size of pterosphenus.  Sea snake lungs are almost as long as their bodies, giving them an impressive capacity for storing air.  They also can fulfill 25% of their respiratory needs through their skin.

All 62 extant species of sea snakes have a venomous bite, so it’s probable pterosphenus did as well.  Sea snake venom is the most deadly snake venom in the world, and it causes instant death for fish.  A quick-working venom is an evolutionary advantage, especially in a watery environment where a snake-bitten fish could swim far enough away that the snake couldn’t find it.  Most species of sea snake don’t bite men, and they can’t even coil and strike, so about the only way for a man to get bitten would be to grab it by the head.  The below map shows the fossil distribution of the Chocktaw giant sea snake.  Note all these localities were underwater then.  The type specimen was discovered in Chocktaw, Alabama, hence the name.  In Georgia a pterosphenus back bone was found in the Hardie Kaolin Clay Mine located in Wilkinson County.  The snake lived in bays and open ocean.

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2 Responses to “Some Remarkable Pre-Historic Snakes”

  1. James Robert Smith Says:

    One of my older brothers was the supervisor of a giant kaolin mine on the middle Georgia/South Carolina border. I’ve never thought to ask him if they encountered any fossils (other than the kaolin itself which is the material from micro-fossils). Of course when I’d visit, the main tools were vast digging vehicles which would have ground up and destroyed any fossils. Still…I should ask him.

  2. markgelbart Says:

    Many marine fossils have been found in kaolin clay mines and also in the vicinity of the former eocene shoreline. The most famous is Georgiacetus voglensis–a primitive whale that is a good example of a transitional species.

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