New light in the North Pacific: Two new species of Typhlotanaidae (Crustacea: Tanaidacea) from the Aleutian region

• Description of two new species of the genus Typhlamia from the Aleutian Trench region. • These are the first confirmed occurrences of the genus Typhlamia in the Aleutian region. • The Aleutian Trench may limit movement and separate populations. The deep-sea paratanaoidean family Typhlotanaidae remains understudied, both taxonomically and phylogenetically, particularly in the North Pacific. This study examines previously undocumented representatives of the genus Typhlamia collected from the Aleutian region. Using an integrative approach that combines morphological analysis and, in one case, molecular data based on 18S rDNA sequences, we identify distinct lineages within the genus. The genetic data reveal a well-supported clade that is clearly separated from the other sequenced members of Typhlamia, suggesting the genus may be polyphyletic and in need of revision. Morphological characteristics further support the distinctiveness of the examined specimens. Their occurrence on either slope of the Aleutian Trench indicate that this region may act as a partial biogeographic barrier, while also hosting previously undocumented deep-sea diversity. These findings highlight the Aleutian region as an important area for understanding the evolution, dispersal, and hidden biodiversity of deep-sea peracarids. LSIDurn:lsid:zoobank.org:pub:8574DCBD-8E4A-40BC-914A-473DC69A4634.