The collection reported here of Palamocladium leskeoides, made in Tennessee, represents the first documented observation of antheridia on this species in North America. Palamocladium leskeoides is a dioicous moss species with a pantropical distribution. Uncommon in the United States, it grows in disjunct populations in moist habitats on calcareous rock. We visited Rock Island State Park (Warren County, Tennessee) in 2019 and relocated a population of this species that was last collected from that location in 1979. Two small voucher specimens were collected and one was observed to have a perigonium containing antheridia attached to the stem. The invasive evergreen Euonymus fortunei was also observed covering surfaces that could otherwise be suitable habitat for P. leskeoides. We plan to assist Rock Island State Park with remediation of invasive plants to improve the available habitat and monitoring the population of this rare moss.