Veilmouth Horror

Istiognathus tarachodi is a species of Terastioikolinine Caligobeloid amphibian from Hades.   The Veilmouth Horror or Eldritchian Veilmouth is a peculiar Hadean organism only seldomly sighted by expeditions departing the Styx Station to venture in the depths of the underworld.   Using the dark environment to its advantage, the predator extends the veil-like muscular membranes around the mouth, putting in full display the array of green bioluminescent spots; The arrangement and amount of the spots mimic the appearance of a small shoal of passive females pressionatatids while the bioluminescent Sphaera Lania in the centre mimics a single larger active male, characteristic gender ratio of some monopressioductatids of Hades.   This illusion lures prey to attack the male at the centre of the shoal, clueless about the true nature of its target, making I. tarachodi a very efficient ambush predator.   The blue bioluminescent ring around the mouth is thought to be a signal to scare off potential predators such as the Soulseers by the use of Batesian mimicry.   The amphibian uses the same aposematic signals as true poisonous animals to warn predators about a fake danger by only partially mimicking the signals of the model to selectively scare off unwanted attentions.   Thanks to Negative frequency-dependent selection, the animal can blend with the model even if only partially mimicking it by thriving in environments where the latter is rarer, thus making their phenotype expression more fit.   Being an ambush predator, I. tarachodi doesn't move often, usually preferring to stay still in the water with its hunting apparatus extended.   When moving, the animal will close the membrane to reduce drag, moving the retractable arm-like armour sections to the sides of the body, assuming a more hydrodynamic shape.   Given the open nature of its environment, the animal will use its powerful echolocation mostly to avoid bumping on other organisms or to keep track of where the ice ceiling is compared to its position.   The animal gained worldwide media attention when it was first sighted by a tracking camera installed on the Ice ceiling, which captured the mysterious creature ambushing prey, sparking a new wave of interest in the ecosystems of Hades and kickstarting a new race to discover what else lurks in the dark waters of the underworld.