#scifilandscape

Goliath Spiny Shark

Kingdom: Animalia

Phylum: Chordata

Clade: Eugnathostomata

Clade/Class: Acanthodii

Order: Ischnacanthiformes

Family: Ischnacanthidae

Genus: Tyrannoselache

Species: T. polycanthus (“many-spines tyrant shark”)

Temporal range: late Miocene to recent (7.7 mya - present)

Information: 

T. polycanthus, better known to the natives of Xenogaea as horduuń/hórduuń (/ˈxo̞r.duːŋ/, “dread”) or mevoskaska/mévoskaska (/ˈmɛ.vo̞.ska.ska/, unknown etymology, likely of pre-Xenogaean substratic origin), and to Western scientists as the Goliath spiny shark, is unusual amongst the acanthodian family (a group of stem-chondrichthians [cartilaginous fishes] colloquially called “spiny sharks”) for its sheer size: around 17-18 feet in length and weighing between 2.7-3 tons, the Goliath spiny shark is one of the largest known non-coelospondyl acanthodians ever discovered, practically rivaling the sizes of its distant shark cousins and with an attitude to match, nearly 100 times the size of its closest known relatives, making it an anomaly amongst its family, its size a mystery, especially amongst an already wide assortment of other large predators in its environment. However, the most commonly-accepted theory is that its ancestors adapted to life in the deep sea before eventually moving back to shallower waters, its size an atavism of its ancestors’ deep sea gigantism. Nonetheless, despite its humble origins, the Goliath spiny shark is still a force to be reckoned with, being notoriously territorial and responsible for many sinkings of small boats and canoes. Like the sharks it is distantly related to, its method of killing prey, although gruesome, is highly effective: prey is usually pursued from below before the animal, with a sudden burst of speed, seizes it, propelling the both of them into the air as it violently shakes its prey to dislodge bite-sized chunks. An incredibly patient and persistent predator, it has been known to stalk prey for several miles, sometimes even propelling itself onto land to chase fleeing prey. Alternatively, prey may be flanked and rammed into from the side before a similar method of dispatching it is utilized. Speaking of prey, as a near-apex predator, the Goliath spiny shark is an opportunistic predator which hunts a wide variety of different prey items, both vertebrates and invertebrates alike. Though sea turtles and cephalopods appear to be some of its favorite prey, it has been known to eat pinnipeds, sirenians, small cetaceans, sea-monkeys/mermaids, small-to-medium-sized marine reptiles (namely plesiosaurs and ichthyosaurs), and several varieties of large reef fish and sharks, hybodonts, and other shark-like fishes. In areas where it shares its habitat with the mud tiger, the two species are known to occasionally prey on one another, and though never confirmed, great whites are notably absent from the areas where the Goliath spiny shark is found, suggesting either predation on young individuals or competition for the same food sources. Individuals living near the edge of the deep ocean may also sometimes venture out into deeper waters to pursue tuna. Scavenging is also quite common. 

Found all across Archaeonesia’s shallow seas, the Goliath spiny shark primarily stalks the waters around kelp forests and coral reefs, though it has occasionally been as much as 10 miles inland. Typically a nocturnal or crepuscular hunter, its eyesight is superb, with its sense of smell, although substantially better than a human’s, being relatively rudimentary in comparison to sharks. Contrary to the stereotypes of sharks and their relatives being ram ventilators, the Goliath spiny shark is not, being able to remain perfectly still on the ocean floor while still being able to breathe, and it does so during the day to rest. While not necessarily gregarious, 2 or more individuals may occasionally work in groups to take down large prey, and cooperation with other large carnivores is also documented. Nonetheless, these animals tend to be territorial and generally do not take kindly to trespassers, chasing off crocodilians and mosasaurs which enter its territory and readily killing other large predators which enter its domain. Cannibalism is well-documented, with larger adults readily consuming subadults and juveniles who stray too close. Notably, however, it will abandon its hunting grounds entirely if large predatory placoderms show up (with the exception of the estuarine flatshark, which it is notably tolerant towards due to pursuing different prey animals), large mosasaurs, and orcas are spotted in its area. Exceptionally intelligent for a fish, it appears to some ability to solve rudimentary problems and seems to be able to way-find with great efficiency, memorizing landmarks or other pieces of the scenery and returning to these areas if hunts have proven successful there before. They also engage in what is believed to be playful behavior, nudging objects in their environment and reorienting them seemingly as a way to stimulate itself when not hunting. Its peculiar habit of arranging objects, namely stones and pieces of corals, in highly-organized patterns across its hunting ground, and its strong tendency to correct their positions when the waves or other animals move them out of place, has consequently earned it the affectionate (and somewhat humorous) nickname of the “OCD fish” or the “autism fish” in online spaces. 

An exceptionally colorful large predator, it is covered in spotted and striped patterns all along its body of varying black and brown hues while its flanks are tan and its underside cream-colored, and during the spring and summer months, when these massive fish breed and when food is most available, the colors of the male will become all the more vibrant. Males will court a female by presenting her with a fresh kill, after which copulation begins. Goliath spiny sharks are internal fertilizers, the males utilizing a pair of modified pelvic fins called claspers to inseminate the female before the two part ways once more. Gestation is quite long, taking anywhere from 10-12 months. Unlike other acanthodians, the Goliath spiny shark is ovoviviparous, giving birth to around 2-4 pups. Cannibalism in the womb is known but does not appear to be common. Nonetheless, when the pups are born, they immediately flee to find cover, as the mother may eat her own young if they linger for too long. For the first decade of their life, they will slowly begin to reach full size, eventually moving out of the safety of the coral reef and into less obstructed waters, around 16-18 years old, they will reach sexual maturity. If all goes well, a young Goliath spiny shark can except to live between 50-60 years.