The Fantail Skipareee

Order: Pseudobatoidiformes

Family: Pseudobatoidae

Genus: Mirobatus

Convergent evolution is the unique adaptation of similar body plans converging on similar niches due to its success in completely different and unrelated groups independently. There are numerous examples of this on Earth, like a fish-shaped body plan with a a fusiform body with a large tail fin for thrust has evolved countless times in completely unrelated clades (ray-finned and cartilaginous fish, mosasaurs, cetaceans, ichthyosaurs, etc.) which is highly efficient for fast, open-water swimming due to how hydrodynamic it is. However, convergent evolution does not necessarily mean that they come upon the same bauplan (occasionally it does, see phytosaurs, champsosaurs and pseudosuchians and very famously, carcinisation), but often have somewhat different body forms which solve the same problem, but in different ways, like how whale sharks and basking sharks are both filter feeders but look nothing alike.

The flattened body plan is the optimal body plan for benthic animals and it has evolved numerous times on Earth. On Alladoras, the wildly diverse array of benthic pelagys have all converged upon flattened bauplans, but the skiparees (Ctenorostria) are by far the most diverse of them, encompassing numerous species which are analogous to stingrays. A very common species, found in sandy seabeds and carpgrass prairie occasionally is the fantail skiparee, a modestly-sized (2 metres in wingspan) is a prime example of its clade, demonstrating many of the unique features of it while also being a quite unique species itself. Skiparees are very unique in that their pectoral fins begin behind their head and ends where the pectoral fins are ancestrally located. This makes a very wide pectoral fin, distanced from their fins, which allows their bodies to be further flattened, and also moves the gill basket upwards. Their dorsal and ventral fins are reduced to allow them to rest comfortably on the sea floor. The front of the pectoral fins jut forward, disconnected to the body and aid them to flush out benthos by 'scooping' out sand. The fantail often spends its days either buried deeply in sand or looking for food on the sea floor, which it uses the barbels lining the edges of its paddle-shaped rostrum to detect vibrations through the water.

Skiparees are unusual for being durophages with only small beak-shaped mandibles which lack any teeth, which seems rather unsuited for this sort of lifestyle, but their only job is to grasp prey and bite off any limbs which may be detrimental to the consumption process, swallowing the hard-shelled body and using the pharyngeal jaws to crush the shell and eat the soft parts. The pharyngeal jaws are a secondary pair of jaws located within the throat, mostly used to draw food into the throat, but in the fantail, they perform a more important role, with the rows of platelike teeth crushing the protective shells of its prey, and then swallowing the soft parts, and regurgitating the larger parts of the shell, with the smaller parts excreted once digestion has finished.

Aside from the unusual way the skiparee consumes its prey, the fantail specifically is unique. Its name, Mirobatus (miracle ray) is due to their frequent appearance after algal blooms. When these algal blooms appear, they attract skiddlecrabs, but deter pelagys as the algae reach poisonous levels. When the algal bloom reduces, skiddlecrabs begin to boom in population, from thousands to hundred thousands in a month. The "miracle rays" arrive, which signals that the bloom has reduced to safe levels and will die out soon, and also heralding a feast, in which soft-shelled skiddlecrabs group in the hundreds of thousands in massive groups, thus maintaining the health of the carpgrass. The fantail skiparee is an important species in these environments, and are one of the many factors relevant for the survival of the carpgrass ecosystems.