Tetsuchū

The are the second breed of insect that Shinan Aburame uses, often time in conjunction with his Nenshōchū. The Tetsuchū are actually an advanced breed of Kikaichū. Shinan's father created the Tetsuchū when a series of his Kikaichū mutated to increase their physical endurance against attacks during the interim between the Second and Third Shinobi World Wars. Shinan's father was able to cultivate this mutation to the degree that the Kikaichū essentially became something new. Insects with body's as strong as metal.

The Tetsuchū are naturally slower than their counterparts, though chakra can be used to speed them up for short periods of time, as a result of having metal-like bodies. They have a life span of a few hours like their counterpart and constantly reproduce within their host in order to keep their numbers high. The wings of the Tetsuchū are also razor sharp, allowing them to slice through opponents. While a single insect would only be capable of delivering a tiny cut, a swarm of them are capable of mutilating an opponent.