Hamatocaulis Hedenäs, 1989.

Hamatocaulis is a generic segregate from Drepanocladus, once a large genus of aquatic to semiaquatic pleurocarps. The leaves of Hamatocaulis are considered plicate but that feature may be difficult to demonstrate on many specimens. However, a careful removal of the leaves, including the bases, from a portion of a stem will reveal one or two small kinks in the leaf scar somewhere between the costa and the leaf margin on both sides of the leaf. The leaves, while falcate, are much broader at the base than most leaves that are considered falcate. That base, on the intact stem, peculiarly is oriented erect and close to the stem with only the distal half of the leaf giving the falcate and secund appearance. Hamatocaulis is restricted to bogs and fens.
see key to Drepanocladus Etc.

Species included:
Hamatocaulis vernicosus (Mitten) Hedenäs