Aquatic macroinvertebrates of Nee Soon 
101 
Fig. 20. Distribution and abundance of order Rhynchobdellida in the Nee Soon drainage. Solid 
circles indicate sites where representatives were collected and circle sizes are proportionate to 
abundance/numbers of individuals captured as reflected in the accompanying legend. 
being ectoparasites which feed on blood, and others being predators which hunt down 
and swallow smaller invertebrates whole (Ruppert & Barnes, 1994). In the Nee Soon 
drainage, one family (Erpobdellidae) from this order has been found in the course of 
this study, and only a single specimen was documented (Site 11) (Fig. 19). 
Order Rhynchobdellida 
The Rhynchobdellida are also known as the jawless leeches, but this common name 
is misleading due to the fact that many leech species from the order Arhynchobdellida 
are also jawless. The true mark of a member of the Rhynchobdellida is the possession 
of a proboscis, which is used to feed. In the Nee Soon drainage, one individual from 
the family Glossiphoniidae was documented (Site 32) (Fig. 20). 
