The Prehistoric Park Animal Field Guide Volume 1

by WildExpert24

As a Prehistoric Park employee, you get the privilege to work with the likes of previously extinct animals. However, if you want to survive longer than five minutes, then you need to have knowledge of its inhabitants. From the world of Cartoon's Prehistoric Park, this Guide will give you info on behavior, diet, lifespan, and more. Welcome to the Ultimate Prehistoric Guidebook.

25. Acheroraptor

Acheroraptor

Scientific Classification

Kingdom: Animalia

Phylum: Chordata

Clade: Dinosauria

Clade: Saurischia

Clade: Theropoda

Clade: Paraves

Clade: Eumaniraptora

Family: Dromaeosauridae

Genus: Acheroraptor

Type Species: Acheroraptor temertyorum meaning "Acheron Plunderer."

Described by David C. Evans, Derek W. Larson, and Philip J. Currie, 2013

Current Park Population: (8; all adults; 4 male, 4 female)

Park Diet: Pre-killed sheep, pigs, and goats, thawed mice, and chicks.

Natural Diet: Small animals like mammals, amphibians, reptiles, birds and small to medium-sized dinosaurs, and young large dinosaurs.

Lifespan: 15 years

Habitat: Open Subtropical Forest, fern prairies, and Swamp floodplains.

Native Ecosystem: Western North America, on what was then an island continent known as Laramidia. Hell Creek Formation, Montana, USA, 67.2-66 Million Years Ago, Maastrichtian Stage.

Breeding Season: April-June

Gestation Period: Three0four months

Eggs Laid: eight to fifteen eggs

Hatching Time: Two-Five weeks

Danger Level: 7 out of 10.

Summary: If there is another iconic carnivore than T. Rex, that is the raptor. One, in particular, is the Acheroraptor, a North American cousin to the famous Velociraptor of Mongolia. Found in Hell Creek it is one of the two geologically youngest known species of dromaeosaurids found alongside the larger Dakotaraptor, and possibly Dromaeosaurus. Despite its small size, Acheroraptor is a cunning, intelligent, and fierce hunter.

Discovery and Naming: Acheroraptor was first described and named by David C. Evans, Derek W. Larson, and Philip J. Currie in 2013 and the type species is Acheroraptor temertyorum. The generic name is derived from the Greek Ἀχέρων, Acheron, "underworld", in reference to the provenance from the Hell Creek Formation, and the Latin raptor, "thief". The specific name honors James and Louise Temerty, the chairman of Northland Power and the ROM Board of Governors, and his wife, who has supported the museum for many years.

Acheroraptor is known from the holotype ROM 63777, a complete right maxilla with several maxillary teeth (some isolated), and from a referred dentary (lower jaw) ROM 63778, both housed at the Royal Ontario Museum, Canada. Both specimens were collected approximately four meters from one another, from the same mixed faunal bonebed that occurs in the upper part of the Hell Creek Formation of Montana, dating to the latest Maastrichtian stage of the Late Cretaceous, immediately prior to the Cretaceous–Paleogene extinction event. The holotype specimen was collected on August 28, 2009, by commercial fossil hunters, one of whom also collected the dentary several years later, and who was later able to provide detailed geographic data from GPS and photographs of the specimen in situ in the ground on the day of discovery. Both specimens were subsequently purchased by the Royal Ontario Museum from a private collector.

Description: They are the size of turkeys almost completely head to toe with thick light brown feathers, with the only bare parts of their bodies being their snouts, feet, and uppermost fingers, the wings, the back edges of the hind legs, and tail feathers were dark gray-brown with black-barred stripes and feather tips, the legs and eye rings were scaly bright gold, the snouts were dark gray and black-tipped, a black stripe marking over their eyes border by white stripes on their faces.

Males have a pale yellow throat and chest with barred light brown stripes and a big head crest mane with black feathers which extends from their neck and towards the back and shoulders.

Females have a white belly and throat and lack feather manes.

Chicks are covered with downy fluff which is tannish brown with black and white spottings with a white underbelly

Classification: The phylogenetic position of the Acheroraptor was explored by Evans et al. (2013) using several data matrices. Both specimens of Acheroraptor were coded as a single taxon into Turner et al. (2012) data matrix, an extensive phylogenetic analysis of theropods that focuses on maniraptorans. Acheroraptor was recovered as a member of the clade containing Eudromaeosauria and Microraptorinae, confirming its referral to the Dromaeosauridae, and possibly to Eudromaeosauria. Within that clade, however, most taxa were recovered in a large polytomy, due to the limited codings available for Acheroraptor.

Evans et al. (2013) also coded the specimens of Acheroraptor (together and separately) into an updated version of the smaller, dromaeosaur-specific dataset from Longrich and Currie (2009). Velociraptor osmolskae and Balaur bondoc were added, Itemirus was excluded (following its identification as a tyrannosauroid by Miyashita and Currie (2009)), and following Turner et al. (2012) the codings for Adasaurus mongoliensis were separated into these based on the holotype from the Nemegt Formation, and these based on IGM 100/23 from the Bayanshiree Formation. Several characters were also rescored and modified, and two maxillary characters were added to the matrix from Turner et al. (2012). This analysis yielded a more resolved topology, placing Acheroraptor in a relatively basal position within the Velociraptorinae, which was otherwise found to include only Asian dromaeosaurids. The cladogram below shows the phylogenetic position of the Acheroraptor following this analysis.

A 2022 study of eudromaeosauria reclassified Acheroraptor as a derived member of Saurornitholestinae, with Atrociraptor as its sister taxon.

They can even scale up and climb up trees to escape large predators and hunt prey as well.

Paleobiology

Social Behavior: They normally live alone or in loosely knitted family packs.

Diet: Acheroraptors fill the niche of the mesopredators in the prey on small mammals, reptiles, birds, and amphibians, occasionally fish and small-medium sized dinosaurs like Leptoceratops, Thescelosaurus, and Trierarchuncus, and young adult dinosaurs like juvenile Pachycephalosaurus, Triceratops, Torosaurus, Ornithomimus, and Edmontosaurus.

Paleoecology: Acheroraptor is the youngest species of dromaeosaurid, and is from the Hell Creek Formation. The Hell Creek Formation is from the time of the Cretaceous-Paleogene Extinction Event and has been dated to 66 ± 0.07 million years ago. Many animals and plants have been found in the Hell Creek Formation, the discovery site of Acheroraptor. As it is known from the Tyrannosaurus-Triceratops fauna, Acheroraptor is the youngest dromaeosaurid, along with the much larger Dakotaraptor.

Evans et al. found that Acheroraptor was the only dromaeosaurid from the Hell Creek Formation. Common teeth previously referred to as Dromaeosaurus and Saurornitholestes would then be considered Acheroraptor. Evans et al. also concluded that there was probably only one dromaeosaurid in the Hell Creek-Lance assemblage. In 2015, this view was disproven, with the description of Dakotaraptor, a far larger second dromaeosaur from the formation. Other non-dromaeosaurid theropods from the formation are tyrannosaurids, ornithomimids, troodontids, birds, and caenagnathids. The tyrannosaurids from the formation are Nanotyrannus and Tyrannosaurus, although the former might be a junior synonym of the latter. Among ornithomimids are the genera Struthiomimus as well as Ornithomimus, and "Orcomimus." The birds known from the formation are Avisaurus, Brodavis baileyi, and two unnamed hesperornithoforms, possibly Potamornis. Only three oviraptorosaurs are from the Hell Creek Formation, Anzu, Leptorhynchos, and the third and undescribed specimen, very similar to Gigantoraptor, from South Dakota. However, only fossilized footprints were discovered as of 2016. The known troodontids from this formation include Troodon, Pectinodon, and Paronychodon. A single species of coelurosaur is known from similar fossil formations including Richardoestesia.

Ornithischians are abundant in the Hell Creek Formation. The main groups of ornithischians are ankylosaurians, ornithopods, ceratopsians, and pachycephalosaurians. One ankylosaurian and two nodosaurians are known, Ankylosaurus, Denversaurus, and possibly Edmontonia. Multiple genera of ceratopsians are known from the formation, the leptoceratopsid Leptoceratops and the chasmosaurines Nedoceratops, Torosaurus, Triceratops, and Tatankaceratops. Hadrosaurs are common in the Hell Creek Formation and are known from multiple species of the ornithopod Thescelosaurus, and the hadrosaurids Edmontosaurus, and an undescribed genus similar to Parasaurolophus. Five pachycephalosaurians have been found in the Hell Creek Formation. Among them are the derived pachycephalosaurids Sphaerotholus, Stygimoloch, Dracorex, Pachycephalosaurus, and an undescribed specimen from North Dakota.

Mammals are plentiful in the Hell Creek Formation. Groups represented include multituberculates, metatherians, and eutherians. The multituberculates represented include Paracimexomys, the cimolomyids Paressonodon, Meniscoessus, Essonodon, Cimolomys, Cimolodon, and Cimexomys; and the neoplagiaulacids Mesodma, and Neoplagiaulax. The alphadontids Alphadon, Protalphodon, and Turgidodon, pediomyids Pediomys, Protolambda, and Leptalestes, the stagodontid Didelphodon, the deltatheridiid Nanocuris, the herpetotheriid Nortedelphys, and the glasbiid Glasbius all represent metatherians of the Hell Creek Formation. A few eutherians are known, being represented by Alostera, Protungulatum, the cimolestids Cimolestes and Batodon, the gypsonictopsid Gypsonictops, and the possible nyctitheriid Paranyctoides.

Interactions with other species: They prey on Leptoceratops, Thescelosaurus, and Trierarchuncus, and young adult dinosaurs like juvenile Pachycephalosaurus, Triceratops, Torosaurus, Ornithomimus, and Edmontosaurus. They normally don't attack the adults as they are larger and more dangerous to them.

Leptoceratops have been known to find back and even in the case of killing and eating an Acheroraptor. Thesecelosaurus and Trierarchuncus use their speed to evade the raptors although Thesecelosaurus can fight back with their legs and sharp beak.

Alamosaurus, Pachycephalosaurus, Triceratops, Torosaurus, Ornithomimus, Edmontosaurus, and Ankylosaurus often ignore them but can be aggressive to the Acheroraptors if they have young. Acheroraptors sometimes feed on the lizards attracted to the flies lured by the scent of dead meat of a large Carnivore like T. Rex.

T. Rex would ignore them but will drive them off if they get too close or when they have young.

Extinction: Acheroraptor would become extinct at the end of the Cretaceous along with Alamosaurus, Pachycephalosaurus, Triceratops, Torosaurus, Ornithomimus, Edmontosaurus, Ankylosaurus, Leptoceratops, Thescelosaurus, Trierarchuncus, and Tyrannosaurus will die out during the K-PG Mass Extinction Event. Although Acheroraptor will benefit from the abundance of herbivore carcasses but will die off from starvation when the carcasses disappear and the small animals are in hiding.

Danger Tip: Despite their size, Acheroraptors can be dangerous, especially in a pack with their cunning and intelligence, they can kill you by pinning you down with their foot claws and restraining their sickle claws, and biting to the throat with their sharp teeth.

Significant Events: On the team's third day of their first mission, a pack of Acheroraptors was encountered attacking a herd of Leptoceratops. Jake transforms into a monster with many arms to distract and scare them. After the pack notices the Leptoceratops herd disappearing into the portal, the Acheroraptor pack follows them to the portal. They now reside in one of the Hell Creek Paddocks.

Hell Creek Paddocks: The Acheroraptor live in one of two separate paddocks in the Hell Creek Region. It is mostly forested with climbing structure logs to allow climbing behavior.

Conclusion: Acheroraptor is the first dromaeosaurids to have in the park and learning from them will help us understand raptor biology and behavior in the future when more species of dromaeosaurs arrive. Acheroraptors are a cunning addition to Paleo 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.

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