The genus Trichoniscoides Sars, 1899 (Isopoda: Oniscidea: Trichoniscidae) from Portugal, with descriptions of three new species

The genus Trichoniscoides Sars, 1899, is exclusively European and comprises 58 species, with 39 occurring on the Iberian Peninsula. Most species in this region are troglobiotic, but recent studies have identified several new species of this genus that are not associated with caves. We describe three new epigean species from northwestern Portugal. All three have a granulated dorsal integument and a hook-like process on the merus of the male pereopod 7. Trichoniscoides castanheirensis sp. nov. is also distinguished by a lanceolate and ciliated tip on the male endopod of pleopod I, Trichoniscoides cordovensis sp. nov. by a male endopod of pleopod II with a pointed tip reinforced by a chitinous shaft, and Trichoniscoides oloensis sp. nov. by a large triangular expansion on the male exopod of pleopod I, which is unique within the genus, along with its ciliated rami. Additionally, we provide distribution maps and a key for all Portuguese species.