After a time it can reach a length of up to 7 cm .
In contrast to other leeches , T. rex does not drop off its host after feeding but can remain attached at the site of its bite for days and weeks .
After a time T. rex can reach a length of up to 7 cm .
In contrast to other leeches , T. rex does not drop off its host after feeding but can remain attached at the site of its bite for days and weeks .