Leeches (Glossiphoniidae)

Taxonomic group

Family: Glossiphoniidae

Diagnostic features

The glossiphoniids are the most common leeches in our fresh waters. Like other leeches they are visibly segmented, very flexible and there is a suction disc at the tail end. The small, pale native Alboglossiphonia is our most common genus, but an introduced glossiphoniid Helobdella is also common in many streams. Helobdella has a more “bumpy” dorsal surface than Alboglossiphonia.

[Alboglossiphonia] (native). Image: Stephen Moore Image — Alboglossiphonia (native). Image: Stephen Moore

[Helobdella] (introduced). Image; Stephen Moore Image — Helobdella (introduced). Image; Stephen Moore

Typical habitats

Glossiphoniids are common in slow-flowing, weedy streams and ponds, particularly in farmland and urban catchments.

Feeding

The glossiphoniid family of leeches are predators of other freshwater invertebrates.

Indicator value

Hard bottom: unassigned; general leech value 3
Soft bottom: unassigned; general leech value 1.2

The tolerance values (ranging from 0 to 10) give an indication of which are the sensitive taxa (values of 8 or more) and which are the tolerant taxa (values of 3 or less). For more information see: Indicator species

Glossiphoniids are found in many freshwater habitats including streams and ponds with poor water quality. This family has not been assigned tolerance values but the Subclass Hirudinea (leeches) have low tolerance values of 3 (hard bottom sites) and 1.2 (soft bottom sites).