part of part of connects connects organ part main bronchus trachea bifurcation of trachea MA:0003114 EMAPA:37555 FMA:7464 UBERON:0015247 bifurcatio tracheae SCTID:361954003 This is the point at which the trachea splits into two (left and right) principal bronchi. It is located in the region of the fourth to sixth intercostal space, though this varies with species and with respiratory phase. This position closely associates the bifurcation with the heart base. The thickened median crest initiating the bifurcation is called the tracheal carina . tracheal bifurcation