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BIOLOGY[]

Testudinata, the turtles, form an ancient clan of amniotes far removed from any other living group. Their lineage can be traced back to the Triassic, when heavily-scaled early turtles with beaks but tooth-paved palates crawled along the banks of rivers, relying on their enlarged armor plates to protect them from predators; their closest known relatives, however, magnificent armored plant-eaters that commonly reached the size of today's biggest panzertoitles, died out at the end of the Permian.

The two most speciose clades of turtles, the Pleurodira and the Polycryptodira, have evolved the remarkable ability to withdraw their heads into their shells by different methods. (Occasionally, this ability has been secondarily lost.)

PLEURODIRA[]

These turtles withdraw the head by bending the neck sideways, and are not quite as rare in Spec as in our timeline.

BRANCHIORECTIDAE[]

Featherbotties are a remarkable group of highly specialized marine pleurodires found in tropical and subtropical reef environments throughout the Indo-Pacific region. They have been linked to the Bothremydidae, a diverse and widespread group of freshwater and marine pleurodires that died out on Home-Earth around the end of the Oligocene, but not enough analyses have been conducted yet that we could state this as a matter of fact.

These colorful turtles possess paired feathery extensions of the endgut (whose proper name is "chelonibranch" but which is almost universally referred to as the "arsegill") that contain closely packed blood vessels. The arsegill can be deployed as a functional breathing organ or retracted into a rectal pouch to avoid damage when the animal is on land or under attack.

Greenback Featherbotty (Brachiorectum viride)[]

The arsegill array of the Red Sea golden featherbotty, Branchiorectum paraureum

The forelimbs have become modified into flippers with 3 – 4 large claws. The hindlimbs are webbed but still retain functional digits. The tail has atrophied to the point where it is no longer externally visible. Featherbotties range in size from a carapace length of 15 to 55 cm.

The featherbotties dwell in high-energy marine areas where the water has a high dissolved oxygen content (e. g. surge channels and seaward reefs). They anchor themselves to a hard surface with their powerful foreclaws and raise their posterior into the current using their hindlimbs as props if necessary. The deployed arsegill supplies sufficient oxygen and expels sufficient CO2 to allow the turtle to remain underwater for days without surfacing. The featherbotties use their powerful beaks to feed on a variety of organisms. Different species prey on small fish, mollusks, crustaceans, echinoderms, coral polyps and algae.

The yellowfin arsegill fish, Chelyphilus flavissimus: one of many colourful species that associate with featherbotties.

A number of fish and crustacean species are known to take refuge in featherbotty arsegills, aggressively defending their hosts against gill-nipping predators. In return, these symbiotic protectors feast on the scraps of the turtle's messy feeding or on plankton and organic debris trapped in the arsegill filaments.

Some species of coral-eating featherbotty (the "bumstingers") store nematocysts extracted from their prey in their brightly coloured arsegill filaments forming a potent anti-predator defesce.

Female featherbotties come ashore to lay their eggs, burying their eggs in beach sand, and often congregate in spectacular arribadas. The hatchlings are exact miniatures of the adults and immediately head back to the water, where they attempt to eke out an existence of the reef. Unlike other marine turtles, featherbotties do not normally migrate far from their nesting sites; this behaviour has led to a high degree of speciation.

Greenback featherbotty, Brachiorectum viride (east tropical Pacific)

23 species of featherbotty have been described, with at least as many on the way. The exact number of species has been obscured by the presence of several widely distributed species-complexes comprised of very similar forms in the South Pacific.

The long-necked featherbotties are small to medium-sized generalist feeders. With their long necks and narrow heads, they probe nooks and crannies for crustaceans, worms, and mollusks. Among this group, the greenback featherbotty (Branchiorectum viride) is one of the smaller species and a common sight on shallow tropical reefs from the Malayan Peninsula southwards to northwest Australia.

Magnificent Bumstinger (Bensenochelys titanus)[]

Magnificent bumstinger, Bensenochelys titanus (Indian and Pacific Oceans)

The largest and most widely distributed featherbotty, the magnificent bumstinger (Bensenochelys titanus) is also one of the most spectacular. This large featherbotty can be found on offshore reefs from east Africa and the Red Sea eastwards to the Philippines and southwards to the northern Great Barrier Reef.

Like other bumstingers, the magnificent feeds primarily on stinging coelenterates, crushing hard corals with its formidable beak. Soft corals, jellyfish and sea anemones are also eaten. The nematocysts of its meals are transferred to the long pale tendrils on the ends of the brightly coloured arsegills. A sting from these tendrils can be quite severe, and divers should exercise caution when around these turtles.

CRYPTODIRA[]

These turtles are characterized by a peculiar jaw muscle arrangement.

MEIOLANIIDAE[]

The horned turtles are small-to-large-sized terrestrial turtles with exclusively vegetarian diets. These animals possess thick shells and stout legs for carrying their weight, and many species sport spines at the base of the neck and on the tail. Because they cannot draw the head into the shell, they protect it by a massive development of bony knobs and outright horns.

This clade of bizarre turtles evolved late in the Cretaceous and, during the Cenozoic, spread throughout the Southern Hemisphere. Today, some horned turtle species dwell in Australia and southern North America, but the most spectacular meiolaniid forms, the panzertoitles, can only be found on the South American pampas.

The great herbivores of the South American pampas are the pseudosauropods and the dinoceratopians, but no less magnificent are the panzertoitles, the massive, horned turtles of the Neotropics. These gentle giants plod staunchly across the plains, bulldozing their way through shrubs and digging in the ground for tubers. Panzertoitles are the largest terrestrial turtles on Spec, and the males quite commonly reach lengths of over two meters.

Panzertoitle (Loricachelonia atlas)[]

Panzertoitle, Loricachelonia atlas (South America – pampas)

With their crown of horns and long, club-like tails, panzertoitles can look quite menacing, but these turtles are actually quite specific in temper. Their tails, reminiscent of the caudal weapons of some of the long-extinct ankylosaurids, despite the fact that some species of ankylosaur still thrive in the world of Spec, are generally only used during male-dominance battles. However, nesting mothers (smaller and quicker than the males) are ferociously protective of their eggs, and it is only at this time when the species becomes dangerous. Many a cazadin who has attempted to steal the eggs of a brooding panzertoitle has left the scene with a broken leg, if at all.

Tiger Tank (Striatochelys difficilis)[]

The largest of the armored turtles in North America, the tiger tank is a species of turtle with a lot of similarities to its South American Cousin, the Panzertoitle. Growing up to the size of an alligator snapping turtle, though not as belligerent as the snapping turtle, these creatures might be slow-moving and docile, but these creatures are not to be underestimated. These creatures have been known to use their mace-like tail to wound potential predators; there are even reports of draks suffering broken bones due to a failed attempt to attack a Tiger Tank. Unlike the vanguards, which use their spiked tails to inflict blood loss on their attackers, the Tiger Tank has been known to break bones. Despite this, the Tiger Tank is a rather peaceful creature, as mentioned earlier.

Gopher Panzer (Geolorica rugosa)[]

The smaller of the two armored turtles, growing to the size of a gopher tortoise back on home earth, the gopher panzer is a rather shy creature, but it will not hesitate to defend itself from an attacker. Interestingly enough, this is the only species of turtle in the world of Spec that is considered as a burrowing species. Similar to the gopher tortoises on home earth. Unlike the gopher tortoise, however, these creatures are decorated with a series of small spikes and a small tail with spikes on it, somewhat resembling the famous Stegosaurus.

POLYCRYPTODIRA[]

These turtles, which means most turtles of both timelines, can withdraw the head by bending the neck in the vertical plane.



- Brian Choo, Daniel Bensen and David Marjanović

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