This possibility (that Chronoperates is a late-surviving basal holotherian mammal) has been hinted at by some other workers.    From Wordnik.com.  [Archive 2006-05-01] Reference

Thirdly, the tooth enamel of Chronoperates is reportedly of pseudoprismatic type, a morphology not present in placental mammals and thus by inference expected in non-mammalian synapsids.    From Wordnik.com.  [Archive 2006-05-01] Reference

Now, if Chronoperates did possess a Meckel’s cartilage, this would be a first for a post-Mesozoic synapsid, and would further support ideas that Chronoperates is actually a late-surviving basal mammal.    From Wordnik.com.  [Archive 2006-05-01] Reference

If this is correct, then the geological range of non-mammalian cynodonts had just been extended by about 100 million years, and it’s for this reason that the name Chronoperates means ‘wanderer through time’ (since 1992, Upper Jurassic and Cretaceous non-mammalian cynodonts have been described, thereby shortening this gap, but I don’t want to cover them here: wait for next post).    From Wordnik.com.  [Archive 2006-05-01] Reference

He concluded that ‘the fossils currently available do not justify classification of Chronoperates as a non-mammalian cynodont’ (p. 278).    From Wordnik.com.  [Archive 2006-05-01] Reference

With a lower jaw that (when complete) would have been less than 30 mm long, and with tooth crowns about 2 mm tall, Chronoperates would have been shrew-sized.    From Wordnik.com.  [Archive 2006-05-01] Reference

In their Classification of Mammal: Above the Species Level, McKenna & Bell (1997) classified Chronoperates as a basal holotherian (Holotheria = kuehneotheriids, spalacotherioids, dryolestoids, therians etc.).    From Wordnik.com.  [Archive 2006-05-01] Reference

The image above (sorry again for the poor resolution) shows the holotype jaw of Chronoperates together with a life restoration of the Jurassic docodont Haldanodon (no life restorations of Reigitherium available, unfortunately).    From Wordnik.com.  [Archive 2006-05-01] Reference

Well, hey, that’s about as exciting as the possibility that Chronoperates might be non-mammalian.    From Wordnik.com.  [Archive 2006-05-01] Reference

Sues argued that the teeth of non-mammalian cynodonts were actually pretty different from those of Chronoperates, that Mesozoic mammals didn’t share pseudoprismatic enamel with Chronoperates, and that the interpretation of the troughs on the dentary as probable attachment areas for post-dentary bones was unconvincing.    From Wordnik.com.  [Archive 2006-05-01] Reference