Information is presented on a recently described dwarf shark, Galeus
piperatus, which occurs through a wide range of depth in turbulent waters
of highly varying physical parameters in Golfo de California, Mexico.
It barely exceeds 300 mm in total length and an egg-case presumed to be
of this species is only 35 mm long. Young about 80 mm long are well
formed and very active. The sexes are remarkably alike in most respects
but differ in tooth structure. The denticles of the young bear a single
hooked spine, but are pedunculated tridents in the adult. The claspers are
large, robust, and of highly complex external and internal structure
