Feces from southern brown bandicoots, Isoodon obesulus, inhabiting the Perth metropolitan area were examined using fecal flotation and light microscopy, and were frequently found to contain oocysts (10/24; 42%). To enable formal description of the proposed new Eimeria species, i.e., Eimeria quenda n. sp., fecal oocysts from 1 juvenile male I. obesulus were allowed to sporulate in 2% potassium dichromate (K2Cr2O7) at room temperature. Sporulated oocysts are spheroidal to subspheroidal 24.5 × 23.6 (22.526.0 × 22.524.8) m, with L/W ratio of 1.04 (1.001.13), lack a micropyle and oocyst residuum, and are contained within a smooth trilaminate oocyst wall 1.8 (1.62.0) m thick. Sporocysts are ovoid, 12.6 × 9.2 (12.013.8 × 8.510.0) m, with L/W ratio of 1.37 (1.201.53), have a sporocyst residuum, and 2 comma-shaped sporozoites, each containing 2 spheroidal refractile bodies. Sporulation takes 13 days at room temperature. This is the second formal description of an Eimeria species parasitic in the order Peramelemorphia.