Brookula Iredale, 1912

Type species: Brookula stibarochila Iredale, 1912, OD.

Distribution: Mainly in the oceans of the southern hemisphere, northern hemisphere records from the Indian and Pacific Oceans only. Shallow water to abyssal depth (Gage & Taylor 1991). Miocene to Recent (Finlay 1924).

Diagnosis: Shell 1.2–2.5 mm, trochoid globose, thin, orthostrophic, paucispiral, dextral, with up to 4 rounded whorls. Periostracum absent. Umbilicus ranges from closed to widely open. Protoconch with smooth or anastomosing ribbed sculpture, up to 400 µm in diameter. Shell sculpture consists of axial ribs; spiral sculpture well defined, but weaker, sometimes overriding and forming beads at intersections with axial ribs; fine growth lines present. Suture deeply constricted. Aperture rounded, with a slightly thickened lip and complete peritreme, nacreous layer absent. Operculum circular, multispiral, with central nucleus.

Radula rhipidoglossate, formula 5­2­1­2­5; rhachidian stout, higher than wide, with cusped edge well serrated. Outer lateral and marginal teeth similar, except for smaller cusps in the latter.

Cephalic tentacles with a dense fringe of sensory papillae at the distal end; foot anterior with two wide, posterior with two shorter lappets, laterally with short, elongate epipodial tentacles without epipodial sensory organs but a fringe of slender hair­like cilia.