A new subgenus of Lastreopsis, subg. Rhopalotricha, is here described based on the results of our recent phylogenetic analyses. Its species differ from others in the genus by having a distinctive type of hair within the grooves of the rachises and costae adaxially. These are 1–3(–4)-celled and clavate, whereas the remainders of the species in the genus have hairs that are 3–12-celled and non-clavate. Subgenus Rhopalotricha also differs by having spores with broadly folded perispores with echinulate surfaces (vs. tuberculate or spiny, and with smooth surfaces). Subgenus Rhopalotricha occurs in the Neotropics, islands of the southwestern Pacific (Samoa, Fiji, and Vanuatu), New Zealand, and Australia. A key is provided to distinguish the species, each of which is treated with synonymy, description, geographic distribution by country, elevation ranges, and discussions. Lectotypes are also designated for Dryopteris amplissima var. subeffusa, Aspidium macrum Fée, and Aspidium latissimum Fée.