Thylacinus megiriani was a quadrupedal marsupial predator, that in appearance looked similar to a dog with a long snout.

Thylacinus megiriani, along with crocodiles and giant monitor lizards, were thought to be the only predators in Alcoota.

The holotype was obtained at the Alcoota fossil area by the geologist Dirk Megirian, whose work in carefully excavating the specimen was honoured by the author in the specific epithet megiriani.

[2] The type material was exceptionally fragmented in its sandstone deposition at Alcoota, requiring the assembly of the dentary for examination and comparison.

Murray's reconstruction is of one larger and more robust dentition and palate than T. cynocephalus, but resembling the gracile and elongated snout, more so than the species T.