Three new species of Spongiopsyllus Johnsson, 2000 (Copepoda: Siphonostomatoida: Entomolepididae) associated with Aplysina cauliformis (Carter, 1882) (Porifera: Demospongiae) from Todos-os-Santos Bay, Northeastern Brazil

Entomolepididae is a small siphonostomatoid family with a distinct shield-like body morphology, comprising 9 genera and 20 species. These genera are divided into two subfamilies, mostly based on their body segmentation, the genera with fused pedigerous somites 2 and 3 are included in the Parmulodinae subfamily, and the genera with free pedigerous somites 2 and 3 are included in the Entomolepinae subfamily. Spongiopsyllus is an endemic Entomolepinae genus, and its four known species are known only of Northeastern Brazil. This study reports three new species of this genus, all found associated with the sponge Aplysina cauliformis. The three new species share 16-segmented antennules, the position of the aesthetasc on the 14th segment, a 2-segmented antennal endopod and 4 setae on the outer lobe of the maxillule. Spongiopsyllus athosi sp. nov. has the maxillule with 3 setae on the inner lobe, and maxilliped endopod 3-segmented with setal formula (2,1,1+claw); S. porthosi sp. nov. has the maxilliped endopod 3-segmented with setal formula (2,2,0+claw); and S. aramisi sp. nov. differs from its congeners by having the antennal exopod with 6 spinules, plus the maxilliped endopod 3-segmented with seta formula (2,1,1+claw). An updated key to the species of the family is provided.