Melvius
Scientific Classification
Kingdom: Animalia
Phylum: Chordata
Class: Actinopterygii
Order: Amiiformes
Family: Amiidae
Subfamily: Vidalamiinae
Tribe: Vidalamiini
Genus: Melvius
Type Species: Melvius thomasi
Described by Bryant, 1987
Species:
-Melvius thomasi, Bryant, 1879 (type)
-Melvius chauliodous, (Hall and Wolburg, 1989 [originally Amia? chauliodous])
Common Name: Hell Creek Bowfin.
Synonym:
-Amia? chauliodous Hall and Wolburg, 1989
Current Park Population: (2; both adults; 1 male, 1 female)
Park Diet: Frozen fish, crabs, crayfish, crickets, chopped earthworms, shrimp, freeze-dried tubifex worms, shrimp pellets, ground beef, beef heart, and beef liver.
Natural Diet: Smaller fish and aquatic invertebrates such as crustaceans, mollusks, aquatic insects, small animals, and young dinosaurs.
Lifespan: 33 years
Habitat: Rivers, Streams, Waterways, Lakes, Creeks, Floodplains, Swamps, lagoons, Estuaries, and brackish water near coastal areas.
Native Ecosystem: Western North America, on what was then an island continent known as Laramidia. Hell Creek Formation, Montana, USA, North America, 74.8-66 Million Years Ago, Kirtlandian-Lancian (late Campanian-Maastrichtian), Early Cretaceous-Present.
Breeding Season: April-June.
Eggs Laid: 2,000 to 5,000 eggs
Hatching Time: One to Two Weeks.
Danger Level: 6 out of 10.
Park Star Rating: 1 star
"I was quite surprised that the specific epithet of the fish has my namesake." -Thomas Tran.
Summary: Melvius was a large amiid fish from the Hell Creek Formation. Amiids are fish that belong to the same family as modern bowfins. It seems to have been a fairly large amiid, and, like modern ones. It was adapted to the murky, under-oxygenated waters of the swamp, often breathing atmospheric air, if the water was too unbreathable.
History of Discovery: The type species, Melvius thomasi, was described by Bryant in 1987. A second species Melvius chauliodous, was named and described by Hall and Wolburg in 1989, and it is now considered to be one of the index taxa of the Kirtlandian land-vertebrate age.
Description: They resemble Bowfins both in anatomy and size. They are dark brown on top with black spots, a dark yellowish green layer around the lateral line, a pale underbelly, and yellowish green fins.
Size: These bowfins measure an average of 1 - 1.5 meters.
Respiratory System: Like gars, bowfin are bimodal breathers – they can breathe both water and air. Their gills exchange gases in the water allowing them to breathe, but they also have a gas bladder that serves to maintain buoyancy and also allows them to breathe air through a small pneumatic duct connected from the foregut to the gas bladder. They can break the surface to gulp air, which allows them to survive conditions of aquatic hypoxia that would be lethal to most other species.
Paleobiology
Diet: It was probably a voracious formidable ambush predator, known to move into the shallows at night to prey on smaller fish like Lepisosteus and Lonchidion and aquatic invertebrates such as crustaceans, mollusks, and aquatic insects. If given the chance they'll prey on small animals and young dinosaur hatchlings. Melvius are remarkably agile, can move quickly through the water, and they have a voracious appetite. Their undulating dorsal fin propels them silently through the water while stalking their prey. The attack is straightforward and swift with a movement that lasts approximately 0.075 seconds. These fish recognize their keepers during feeding and swim to the surface in anticipation of their next meal.
Life History: Melvius reach sexual maturity at two to three years of age. Melvius spawn in the spring or early summer, typically between April and June, more commonly at night in abundantly vegetated, clear shallow water in weed beds over sand bars, and also under stumps, logs, and bushes. Optimum temperatures for nesting and spawning range between 16–19 °C (61–66 °F). The males construct circular nests in fibrous root mats, clearing away leaves and stems. Depending on the density of surrounding vegetation there may be a tunnel-like entrance at one side. The diameter of the nests commonly ranges between 39–91 cm (15–36 in), at a water depth of 61–92 cm (24–36 in).
During spawning season, the fins and underside of male bowfin often change in color to bright lime green. The courtship/spawning sequence lasts one to three hours and can repeat up to five times. Courtship begins when a female approaches the nest. The ritual consists of intermittent nose bites, nudges, and chasing behavior by the male until the female becomes receptive, at which time the pair lie side by side in the nest. She deposits her eggs while he shakes his fins in a vibratory movement, and releases his milt for fertilization to occur. A male often has eggs from more than one female in his nest, and a single female often spawns in several nests.
Females vacate the nest after spawning, leaving the male behind to protect the eggs during the eight to ten days of incubation. A nest may contain 2,000 to 5,000 eggs, possibly more. Fecundity is usually related to the size of the fish, so it isn't unusual for the roe of a large gravid female to contain over 55,000 eggs. Bowfin eggs are adhesive and will attach to aquatic vegetation, roots, gravel, and sand. After hatching, the larval bowfin does not swim actively in search of food. During the seven to nine days required for yolk-sac absorption, they attach to vegetation utilizing an adhesive organ on their snout and remain protected by the parent male bowfin. Bowfin aggressively protects their spawn from the first day of incubation to a month or so after the eggs have hatched. When the fry can swim and forage on their own, they will form a school and leave the nest accompanied by the parent male bowfin who slowly circles them to prevent separation.
Interactions with other species: Often ignored by the large dinosaurs, adults and young are most vulnerable to predators like Pectinodon, Dromaeosaurus, Acheroraptor, Anzu, Quetzalcoatlus, and juvenile T. Rex, Lonchidion, predatory fish like Melvius, packs of Didelphodon, Borealosuchus, Thoracosaurus, Champsosaurus, Brachychampsa, Axestemys, Palaeobatrachus, Scapherpeton, Habrosaurus, and even other Melvius.
Adults would prey on Palaeobatrachus, and young Scapherpeton, Lonchidion, Melvius, Myledaphus, Casterolimulus, Lepisosteus occidentalis, and Paleopsephurus. They would catch small animals and young dinosaurs that swim in the waterways or come to drink.
Extinction: Due to Freshwater acidification and changing water temperatures would lead to the demise of the Mevlius. Only two species the Bowfin and Eyetail Bowfin.
Danger Tip: Angry and aggressive, the Melvius is a tough, angry fish to fight at the end of a line. Wear gloves when handling as a bite might lead to bacterial infections.
Significant Events: On the Team's Final Day of their First Rescue Mission, the team comes upon a pair of Melvius alongside Lepisosteus occidentalis, Lonchidion, Paleopsephurus, Myledaphus, and a group of Casterolimulus crawling along the river alongside amphibians, Habrosaurus, and Scapherpetons. They were captured in nets to be transported to the Park. They now reside in the Hell Creek Forest Building.
Hell Creek Forest Building Aquarium: This large tank houses most of the Hell Creek Fishes and aquatic life like Casterolimulus, Paleopsephurus, Lonchidion, Lepisosteus occidentalis, and Myledaphus replicating the freshwater waterways, visitors can view them with underwater thick glass panel viewing. You might get a glimpse of one of the Melvius taking gulps of air from the surface.
Conclusion: For anglers who love to catch fish like Bowfin would be bewildered when they learn that this ancient fish has been around during the age of the dinosaurs. The Melvius is a formidable fish worthy of seeing at Prehistoric Park.
The Field Guide might take a long time, like structuring and writing descriptions of the creatures, but also my time in college and spending time with my family. So you can suggest additional information quotes, descriptions, and natural or speculative behaviors for the prehistoric animals that I can edit and you send your suggestions either in reviews or Private Messages.
Examples: Inferring what the toons are doodling on the sketches or snarking quotes.
Negative, hateful, and spam comments are not allowed and will be reported, this is WildExpert24 signing off.