In the early days of Specworld exploration, legendary specbiologist Tiina Aumula led many expeditions into tropical Asia and northern Africa. Among the countless new specimens obtained from these forays were a number of graceful "raptor"-type theropods that were clearly very different animals from the more heavy-set draks of the family Boreonychidae.


These tropical predators soon gained widespread attention when initial studies suggested that they were modern representatives of the Troodontidae. These were slender birdlike theropods of the Late Cretaceous with numerous small teeth and large brains. The new gracile raptors were assigned to this family with little hesitation and were informally known by the horrid mouthful of "Spec-troodont". Today, these forms are known by the more pronounceable name of "mattiraptor". Although the mattiraptors are a highly varied group of theropods, they share many features that indicated a troodont ancestry including:

  • all the initially described species had long, low snouts that lacked any form of bony protuberances.
  • elaborate craniofacial sinus system with a bulbous parasphenoid capsule. - troodont-like metatarsus: laterally compressed mII, strongly pinched mIII, stout mIV. - poorly developed "terrible claw".
  • fused calcaneum & astragalus.

However it was also apparent that these "spec-troodonts" possessed a number of very un-troodont-like characteristics such as:

  • smaller tooth count than Cretaceous troodonts (76 in Bennumimus as opposed to 122 for Troodon)
  • teeth that do not bear more than a superficial resemblance to troodont teeth, being comparatively larger and lacking the characteristic constriction between root and crown.
  • vertebrae lacking any troodontid peculiarities.
  • well developed olfactory bulbs.
  • strongly opisthopubic dromaeosaur-like pelvis.

The most unusual feature of the mattiraptors is the unusually mobile first toe. This rather long digit is able to rotate against the other toes and in some forms, formed a sort of pedal-thumb, rather like the opposable hallux of a perching bird. This feature is well developed in Bennumimus and the recently discovered Nanoraptor, while it has been secondarily lost in forms like Echinornithoides.

These differences were noted and passed off as the result of 65 million years of evolution from a Troodon-like ancestor. All this was well and good until the discovery of the arboreal "troodont" Nanoraptor (the "verminator") by David Namen.

This little African theropod, while clearly showing strong similarities to the "spec-troodonts", also bore a short snout filled with dromaeosaur-like teeth and a primitive metatarsus that lacked troodont-like features (the metatarsal III is only weakly pinched). This enigmatic animal prompted DNA hybridization tests to ascertain its relationship to the other "troodonts", as well as to the more conventional dromaeosaur-type deinonychosaurs. When this study yielded unexpected results, the project was expanded into an exhaustive genetic study comparing all the Specworld's raptors.

Firstly, the verminator was clearly a "spec-troodont", not some aberrant arbronychosaur as some had suggested. Secondly, the "spec-troodonts" as a whole were genetically very similar to the Hesperonychidae (American raptors) with mitochondrial DNA studies suggesting a divergence time of no later than the Oligocene. This strongly suggested that these gracile raptors were not late-surviving troodontids, but rather the highly derived products of a late Paleogene radiation of dromaeosaurs.

The superfamily Mattiraptoroidea was erected to accommodate the former Specworld Troodontidae which were now considered to be diverse enough to be split into several families. The common ancestors of the mattiraptors and hesperonychids probably spread their North American range into Eurasia and Africa during periods of marine regression in the Early Oligocene. One lineage became arboreal omnivores for which they developed their unusually dexterous digit I. During the loss of forest habitats in the Miocene, most came down from the trees and began branching into the collection of terrestrial mattiraptors that we see today.

There are true troodonts still living in Spec, but their numbers have been greatly reduced.


The most primitive family of mattiraptors, monotypic Nanoraptoridae is distinguished by its similarity to the other deinonychosaurs in the form of teeth, "primitive metatarsus" and opposable first toe, lost in more advanced mattiraptors.

These two species are the only well-documented members of Nanoraptoridae. Material is still coming out of Africa suggesting more species, but nothing solid yet. From several traps, remains, and photographs, we are beginning to understand the verminator's physiology and lifestyle. They are small predators that are well adapted for tree life. Their reversed hallux allows for easy branch gripping, and their strong arms also increase stability. During the night, they feed mostly on mammals, both terrestrial and arboreal.

Basin Verminator (Nanoraptor congoi)

The basin verminator is a cat-sized mattiraptor that populates most of the Congo Basin and parts of southern Africa. Some of the smallest of all Spec theropods, these verminators doggedly hunt a wide range of prey, mostly mammalian. Basin verminators spend most of their time in the trees. They only come down to the forest floor during the night, usually to ransack mammal burrows. Lately, they seem to have developed the bad habit of looting Spec scientists' camps during the night.

The two species of the Nanoraptor genus. Top: Basin verminator, Nanoraptor congoi (Central Africa: the Congo Basin) Bottom: Silver verminator, Nanoraptor dui (Eastern Africa: Great Rift Valley)

Silver Verminator (Nanoraptor dui)

The silver verminator was the second species of verminator discovered. It is usually located in the Great Rift Valley forests. Its shiny pelt ranges from gray to black, depending on the region, and they tend to be more robust then their Congo relatives. Each solitary hunter guards a plot of forest real-estate from other competitors. When a territory is invaded, the defender will chase off the intruders with gaudy screams and howls.


Stork-like benumimes haunt the wetlands of the Africa, Mediterranean coast, Asia Minor, and the Indian Subcontinent. Highly derived mattiraptors, benumimes are adept fishers, using flexible necks and long, tooth-filled jaws to snatch slippery fish and other small, aquatic animals. The killing claws on the inner toes are vestiial, and are used in some species for grooming or for ritual combat. Benumimes are also distinct in their reversed opposable first toes giving their feet a distinctive, birdlike oot print. This primitive feature of mattiraptors, lost in the more advanced harracks, unites the bennumimes with the verminators.

Egyptian Bennumime (Bennumimus aegyptianus)


Egyptian bennumime, Bennumimus aegyptianus (Northern Africa: Nile Delta)

The largest and most famous of the bennumimes, the Egyptian bennumime can be found in the Nile Delta and the few other places in northern Africa wet enough to support river life. The Egyptian bennumime stands about as tall as a man, and besides fishes it also eats small amphibians and mammals. Their vocal calls have been known to sound like cats.


Clade Vulpessauridae is the most specious group of the mattiraptors, and those most similar to the troodonts. The largest vulpessaurs are nocturnal, using their keen ears and stereoscopic vision to locate prey.

Woofer (Vulpessaurus nameni)


Woofer, Vulpessaurus nameni (Central and Southern Africa)

Eurasian Harrack (Vulpessaurus avidus)


Eurasian harrack, Vulpessaurus avidus (Northern Eurasia)

Named after their harsh, croaking calls, the Eurasian harrack is a vulpessaurid that is very common all around Northern Europe. These 1.2 m long predators hunt small mammals and often use their long forelimbs to dig them out from their holes. They also catch small birds and scavenge. Harracks live in very loose packs, with each individual protecting its own territory, but when a large food resource - such as a ceronychid carcass - is located, the harrack that found the food will call the others to feed (after it has finished eating, naturally).

Eurasian Harrack and salmonite, see The Salmonite Run

Nirvi (Boreopteryx nirvi)

A common predator in Northern Eurasia and North America, these species of mattiraptoroidea are actually one of the few species that specialize in scavenging carcasses.

Nirvi, Boreopteryx nirvi (Northern Eurasia and North America)

St. George's Skreet (Serpephagus georgi)

This species specializes in hunting and killing snakes. Their cries have been known to sound more melodious, especially during the mating season.

St. George's skreet, Serpephagus georgi (Southern Asia and Africa)


A skreet doing what it does best: killing snakes.

Corant (Anguivenator indicus)


Corant, Anguivenator indicus (Southern Africa)

The corant is a skreet-like predatory mattiraptor known especially as a serpent hunter. Recent analysis suggests that the corant and St. George's skreet are more closely related to each other than either is to Vulpessaurus.

                                                  ,=N. congoi  (Basin verminator )  
                      |                           |
                      |                            `=N. dui  (Silver verminator)
                  |   `=Bennumimidae=Bennumimus aegyptianus ( Egyptian bennumime ) 
                  |                                    ,=V. longipes (Vulpessaur )
                  |                                    |
                  |      ,=Vulpessauridae=Vulpessaurus=| 
                  |    |                               |=V. avidus (Eurasian harrack ) 
                  |    |                               |
                  |    |                               |
                  |    |                               |
                  |    |                               `=V. nameni (Woofer)
                  |    |
                  |  ,=|
                  | |  |
                  | |   `=Boreopteryx nirvi (Nirvi)
                  | |
                    |   ,=Serpephagus georgi (St. George's skreet)
                        `=Anguivenator indicus (Corant)
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