Schismatoglottis porpax S.Y. Wong, Kartini & P.C. Boyce (Araceae) is described as a new species of the Schismatoglottis Multinervia Complex and compared with congenious species, notably with the morphologically closest taxon S. hayi. Schismatoglottis porpax raises the number of species in the Multinervia Complex to five, and furthermore represents the first record of the Multinervia Complex for Sabah. Schismatoglottis porpax is illustrated from living plants, and the spadices of the five described species of the Multinervia Complex are compared.