What is "arthropleura"

Arthropleura \Ar`thro*pleu"ra\, n. [NL., fr. Gr. 'a`rqron joint + ? the side.] (Zo["o]l.) The side or limb-bearing portion of an arthromere.

Arthropleura ( Greek for Jointed Ribs) is a genus of extinct, 0.3–2.3 metre (1–7.5 feet) long millipede arthropods, native to the upper Carboniferous of what is now northeastern North America and Scotland. The larger species of the genus are the largest known land invertebrates of all time, and would have had few, if any, predators.