Key to the species of Ascoleucetta

1. Atrial skeleton composed of spicules exclusive of this region........................................... A. amitsba

- Atrial skeleton composed of spicules occurring also in other regions of the sponge.................................. 2

2. Diactines are present................................................................................... 3

- Diactines are absent..................................................................... A. sagittata sp. nov.

3. Microdiatines around the inhalant apertures....................................................... A. ventricosa

- Trichoxeas around the inhalant apertures......................................................... A. compressa