How many species of marsupial moles are found in the Australian interior?

Marsupial moles are highly specialized marsupial mammals, known from two species found at the Australian interior.

Notoryctes typhlops (southern marsupial mole, known as the itjaritjari by the Pitjantjatjara and Yankunytjatjara people in Central Australia).

Notoryctes caurinus (northern marsupial mole, also known as the kakarratul)

Notoryctids are small, fossorial mammals that anatomically converge on other fossorial (and distantly related) mammals, such as living golden moles (Chrysochloridae) and extinct epoicotheres (Pholidota).

Like chrysochlorids and epoicotheres, notoryctids use their forelimbs and enlarged central claws to dig in a parasagittal (i.e., up and down) plane, as opposed to the "lateral scratch" style of digging that characterizes talpid moles.

Marsupial moles spend most of their time underground, coming to the surface only occasionally, probably mostly after rains. They are blind, their eyes have become reduced to vestigial lenses under the skin which lacks a pupil. Therefore they are functionally blind. They have no external ears, just a pair of tiny holes hidden under thick hair.