Arthurdendyus testaceus is a species of land planarian belonging to the tribe Caenoplanini.

It is native to Australia and New Zealand.

[1] The body of Arthurdendyus testaceus is long and tapers to a point at each end; it is around 7–8 cm in length.

The dorsal side is a red color, ranging from a dull brick-red to a bright cherry-red.

This flatworm- (or platyhelminth-) related article is a stub.