Notably, until its discovery it was supposed that " Thylacosmilus " was a close relative of the family Borhyaenidae, or even a specialized member of the same, having emerged in the late Miocene; the most primitive characteristics and age of " Anachlysictis " suggest a previous origins of the thylacosmilids at the base of the superfamily Borhyaenoidea, whose monophyly needs review.
22.
In attacking prey ( but probably not necessarily in a defensive situation, as it was too slow-moving ) it most likely was the dominant carnivore of Miocene Patagonia, being able to kill even large animals such as the elephant-like " Astrapotherium " and in the predatory role being on par with a pack of " Thylacosmilus " ( metatherian sabre-tooth ).
23.
Unlike other remains assigned to the family Thylacosmilidae ( a group of metatherian predators equipped with " saber teeth " ) that had been found previously, " Anachlysictis " is the first record of such borhyaenoids in northern South America, and also most primitive and ancient in the family ( in fact, is the first confirmed record that did not belong to the genus " Thylacosmilus ", until the official publication of " Patagosmilus " in 2010 ).
24.
"Anachlysictis ", unlike its better known relative, " Thylacosmilus ", was smaller, weighing around 18 kilograms ( ~ 8.16 pounds ), and the specialized features of the latter such as the flanges on the lower jaw to adjust the fangs were smaller ( due to the upper canines not being as long, in terms of proportions ) and lacked the rim of the eye socket, which would give to the skull a flattened profile.
25.
This is because, as in other related predatory saber-toothed species, such as " Thylacosmilus " and the cat " Smilodon ", this muscle is reduced, leaving more space for the jaw joint to increase its opening angle, which although affecting mandibular power is compensated because they do not need such a large bite force to use their canines because they let the well-developed neck muscles bring down the skull and allow the fangs to cross through the flesh of their prey.
