Damage from western corn rootworm (WCR; Diabrotica virgifera virgifera) can cause significant yield loss in corn production regions of North America and Europe. Corn rootworm traits developed based on Bacillus thuringiensis proteins have been an important tool utilized by growers in North America to counter this loss. However, the potential for resistance to these trait proteins has generated urgency to develop new traits that can complement or replace existing rootworm traits. In this context, a protein designated IPD079Aa was identified from the fern, Huperzia phlegmaria, which demonstrated activity against WCR. Sequence homology-based screening led to the identification of a related protein, IPD079Ea from the fern Ophioglossum pendulum, that also had high WCR activity. Interestingly, IPD079Ea exhibited broader spectrum of activity (including southern corn rootworm; Diabrotica undecimpunctata) than IPD079Aa and provided excellent root protection when expressed in transgenic corn. This led to more detailed studies to understand the mode of action of these proteins. Based on sequence, IPD079Ea structure was predicted to include an N-terminal MACPF domain coupled to a C-terminal beta prism domain, consistent with a pore forming mechanism of action. Binding studies were conducted using brush border membrane vesicles (BBMVs) from WCR which revealed that these IPD079 proteins bind specifically to BBMVs through the same receptor. More importantly, IPD079Ea did not share binding sites with proteins that are surrogates for current WCR commercial trait proteins (Cry3 or Cry34/35), indicating low potential for cross-resistance. Similar binding studies with IPD079Ea using BBMVs from insensitive lepidopteran insects showed no binding under conditions tested, consistent with specific receptor recognition for insecticidal activity. Overall these results show that IPD079Ea has great potential for development into a trait with a new mode of action for protection against corn rootworm damage. These and other data related to the mode of action of IPD079Ea will be presented.