I. australis

I. australis may refer to:
 * Ictalurus australis, the bagre del panuco, a fish species endemic to Mexico
 * Ichthyococcus australis, the Southern lightfish, a fish species
 * Icichthys australis, the southern driftfish or ragfish, a medusafish species found around the world in all southern oceans
 * Indigofera australis, the Australian indigo, a leguminous shrub species