Karkapneumids

 

Kingdom: Animalia
Phylum: Arthropoda
Subphylum: Crustacea
Class: Malacostraca
Order: Decapoda
Suborder: Pleocyemata
Infraorder: Anomura
Superfamily: Paguroidea
Family: Parapaguridae
Subfamily: Karkapneumidae
Genus: Desicundus
Species: D. achlanutis

Common name: achlanut crab, karkachla

The achlanut crab, as can be seen in the taxonomy chart, belongs to the subfamily Karkapneumidae. This is an amalgam of the Greek words for "lung crab". While not possessing lungs in their true sense, the achlanut crab does possess a pair of brachiostegal lungs, similar to the ones found in Holocene coconut crabs.

The achlanut crab is actually quite similar to the Holocene coconut crabs of the Indian and Pacific oceans, though this is more a feat of convergent evolution than of relation. One could say that the achlanut crab is just an Atlantic version of this behemoth of the Holocene arthropods. Those who say that would, superficially, be correct. But ultimately, they’d be wrong.

Similarities to the coconut crab end at the superfamily level and at the respiratory level. Both are paguroids, but the coconut crab is a coenobitid rather than a parapagurid.

True, the aclanut crab is the largest arthropod in Platonia, but it is still dwarfed by the coconut crab. The achlanut crab measures just a little over 12 inches long, compared to the 16 inch length of the coconut crab.

It gets its scientific name from two traits.

The species name (D. achlanutis) comes from the achlanut crab’s diet of achlanuts, which is a new species of pear that possesses a tough skin. Not coconut tough, but more rubbery and a lot harder.

The genus name (Desicundus) comes from the Greek word “desios” meaning “right-handed” and the Latin word “indicundus” meaning “steroid” Essentially, Desicundus means “right-handed steroid”. It earned this name because the achlanut crab’s right claw is considerably larger than the other. Though this is only in males.

This enlarged claw is used to harvest achlanuts. The claw has serrated “teeth” on the inner surface. This is used to saw through the stem of the achlanut. A group of males (usually four) climbs up a tree with a sufficient supply of achlanuts, then they set themselves to the task of chopping through the stems.

After a sufficient amount is harvested, the males descend the tree and join the rest of the group, which usually is one hundred strong (males and females included).

Mating usually occurs on the beach. The males all make a show of lifting their right claw in a manner similar to fiddler crabs. The males with the most impressive display (and thus the largest claw) then mate, and the females lay the fertilized eggs in tide pools.

For all of their non-mating adult life, achlanut crabs live in the interior forests. As such, their time on the beach leaves them quite vulnerable to predators, the beach-combers chief among them.

Tracholanids

 

Before I get into talking about two tracholanid species, I'd like to discuss this group's evolution.

The red-eared slider, introduced to the United Kingdom during the Holocene (which, by the way, is a shorter way of saying the Human Era), is the ancestor to this lineage of giant turtles that echo those of New Caledonia and the Galapagos. Common throughout the UK (and the rest of western Europe after man's demise), this aquatic turtle was poised to evolve into large herbivores when it reached Platonia.

The red-eared slider possessed a weak keel, which, in its tracholanid descendents, has evolved away to make way for a larger size.

There are three genera in the tracholanid family, and I shall present one of each.

Horned Trapper

 

Kingdom: Animalia
Phylum: Chordata
Class: Reptilia
Subclass: Anapsida
Order: Testudines
Superfamily: Testudinoidea
Family: Tracholanidae
Genus: Taurufus
Species: T. casses

Common name: horned trapper

The horned trapper, like all tracholanids, is descended from the red-eared slider. Their ancestor was an omnivore and, on Platonia, this led to a mass increase in diversity. While most tracholanids are herbivores, those in genus Taurufus are carnivores.

Of particular note is the horned trapper, hunting in a similar matter to another Holocene turtle. The alligator snapping turtle, as well as its cousins, makes use of its tongue, which has evolved to imitate a wriggling worm and could thus lure their fish, amphibian, and other prey.

A similar method is utilized by the horned trapper. Only, the horn trapper is terrestrial.

Thus, the horned trapper’s tongue has evolved to lure terrestrial prey, such as skip-birds. These tiny passerines (which I shall describe later) are primarily herbivores, but will not shy away from insects or even a dead achlanut crab.

It is the latter that is used to lure a skip-bird into the horned trapper’s mouth. The tongue has lengthened and become redder with some small brown specks. This all to imitate a crab leg. The head has even become redder to imitate a crab’s body. The red “ears” of the red-eared sliders have also evolved into red horn-like extensions to imitate two pincers.

This lure is quite effective and, through slight wiggling of the tongue, the skip-bird is lured directly into the mouth, making for an easy meal.

The horned trapper measures 26 inches from head to tail. Its carapace is mottled green and brown in order to blend in with the grass. Its plastron has been remained relatively unchanged, save for the fact that is has been reduced slightly. Because of this, horned trappers and other members of Taurufus still possess a sprawled leg stance. The other two genera have more erect stances.

Quote:

 

Kingdom: Animalia
Phylum: Chordata
Class: Reptilia
Subclass: Anapsida
Order: Testudines
Superfamily: Testudinoidea
Family: Tracholanidae
Genus: Grompikerkis
Species: G. lamargos

Common name: kanabo turtle

The kanabo turtle is a tracholanid that has evolved to take the place of pigs on Platonia. From the tip of its tail to the top of its head, it measures 60 inches. Fifteen inches of that length gave the kanabo turtle its name.

The genus name Grompikerkis comes from two Greek words, which, together, mean “knobby tail”. It’s not like the tails of the prehistoric ankylosaurs, not at all. Sure, the same principle applies, but it’s not very similar.

The fifteen inch length of the tail is covered in hard knobs, looking more like the kanabo club used by Japanese samurai (hence its common name). Its shell does provide sufficient protection from predators, yes. But, since the plastron is so greatly reduced (more like a rectangle with a circle in the center) (to allow for an erect stance and efficient leg movement), its stomach is vulnerable. To combat predation, the knobby tail evolved.

Kanabo turtles are loners outside of mating season. Adults generally hang out in more open spaces, seeing as their diet consists of grasses, bushes, shrubs, and bird eggs, though it is quite generalistic.

Young kanabo turtles, on the other hand, hide out in the dense forests making use of their large numbers and the cover. Despite their best efforts, only about twenty kanabo turtles from a clutch of fifty will survive to adulthood.

Mating occurs year-round, though females will only breed once a year. Kanabo turtles generally reach maturity around twenty years of age, and they’ll live to about sixty.

Platonian tortoise

 

Kingdom: Animalia
Phylum: Chordata
Class: Reptilia
Subclass: Anapsida
Order: Testudines
Superfamily: Testudinoidea
Family: Tracholanidae
Genus: Tracholanis
Species: T. ulanawa

Common name: ulanawa

The ulanawa is the only species in its genus, but it is also the first tracholanid discovered and the reason for the family name.

Named after the Cherokee word for “turtle” because its shell looks like a very very tiny island when sticking out of the water, the ulanawa is more aquatic than its tracholanid cousins. But not by much.

You see, the ulanawa is about 54 inches long, and stands at a height of 40 inches. Its plastron is greatly reduced, being little more than seven inches across. This gives it a fully erect stance and allows it to stand up in the water. Its feet aren’t webbed and it wades rather than swims. So, technically, it’s only aquatic in that it spends much of its time in the water.

The ulanawa subsists on a diet of various water plants. It has a “saddleback” shell to allow it to reach its neck out of the water to breath. In order reach plants and to reach above the surface, its neck has grown longer. When fully outstretched, it can another foot to the ulanawa’s body length (note: the 54 inch length does not include the neck).

When on land, it is often a target for predators, due to its exposed stomach and possessing a lot of meat. The ulanawa combats this by spending as much time in the water as possible and, when on land, laying on its stomach as much as possible.

Mating generally occurs in the spring time. Like their ancestors, the ulanawa mate in the water. But unlike their ancestors, they only lay a small amount of eggs (only about five). Due to laying such a small number, the ulanawa exhibit a behavior unheard of in other turtles: they actually care for their young.

Females will dig a hole in a mud wall near the river and lay her eggs in there. She will check up on them periodically and, once hatched, she will deposit food in the nest. Once the young outgrow the nest, they will leave and watch their mother for a couple months, learning what is safe to eat and what is not. After this period of time, the mother abandons her young so they can fend for themselves.

And there you have it. Three iconic tracholanids. If you notice anything off (like maternal care in the ulanawa or the reduced plastron in the latter two species), please let me know. I couldn’t find as much information as I wanted.

• Option #1: the North American grasslands of 15MYH. Main attractions: pronghorn radiation and urocyon radiation.
  
  
• Option #2: the Russian plains of 100MYH. Main attraction: club-tailed birds.
  
  
• Option #3: the Alaskan swamp of 190MYH. Main attraction: completely different mammals and birds. Rise of saltokochlids.