Seeds diffusion involving ants is a key link in the renewal of plant populations in desert ecosystems. Analyzing the interaction mechanisms between ants and plants is of great value for the conservation of endangered species. This study focused on Ephedra rhytidosperma， a plant species endemic to the Helan Mountains. Through field behavior observations （continuous tracking and recording for 3 days）， controlled experiments （removal treatment of aril， density gradients of 10， 20 and 30 individuals·m^-2） and combined with laboratory analysis， this study revealed the mechanism of action of Cataglyphis aenescens in the seeds dispersal of this species. The results showed that the peak of seeds transportation by Cataglyphis aenescens occurs from 10：00 to 11：00 in the morning， with an average transportation distance of 4.0 meters. The aril， due to its high nutritional content， has become a key factor affecting the transportation of Ephedra rhytidosperma seeds. The transportation quantity of Cataglyphis aenescens for the three different types of targets is as follows： intact seeds > aril > seeds with aril removed， and the transportation efficiency also decreases after aril removal. Cataglyphis aenescens shows bidirectional regulation in the transportation of seeds of different densities. High-density seeds are more likely to attract ants， but the removal rate is lower. This study revealed the nutritional reciprocity mechanism of Ephedra rhytidosperma seeds diffusion mediated by Cataglyphis aenescens， providing an important scientific basis for the recovery of endangered plant populations in desert ecosystems.

Ephedra rhytidosperma  /  Ant propagation  /  Aril  /  Seed density