Black Millipedes. It's about 4cm. Body dia is only about 2.5mm
小紅黑馬陸 Leptogoniulus sorornus
體長約40mm, 身體以紅色和黑色為主, 近腳的地方也是紅黑色的。
Millipedes are myriapods of the class Diplopoda that have two pairs of legs on most body segments. Each double-legged segment is a result of two single segments fused together as one (the name "Diplopoda" comes from the Greek words διπλοῦς (diplous), "double" and ποδός (podos), "foot"). Most millipedes have very elongated cylindrical or flattened bodies with more than 20 segments, while pill millipedes are shorter and can roll into a ball, like a pillbug.