https://multituberculateearth.wordp.....cia-formation/
https://sites.google.com/view/allot.....ucia-formation

Another tiny insectivore is the mole sized Tumi yumi, more robust and heavier than Sorilestes andina. This is South America's only Palaeogene microcosmodontid, a lineage that diversified in the northern continents both as small insectivores and eventually as carnivores, some of the largest terrestrial mammalian predators of all time. None of that grandeur is seen in this tiny South American offshoot, which didn't even leave descendents. It appears to be closely related to weasel-like forms in North America, which makes its subterranean habits quite perplexing, especially since necrolestids also occur in the Santa Lucia Formation. It indeed converged upon them in several ways, most notably its large clawed forelimbs. The skull is shorter, but bears massive lower incisors and shearing molars and plagiaulacoid, which might suggest a speciation towards larger prey like beetles and small vertebrates.