Key to species of Flagellotrema Ozaki, 1936

1 Oesophagus with only 1 complete clockwise loop; excretory papilla small, yet distinct .............................. .......................................................................................................................... F. convolutum Ozaki, 1936 .

- Oesophagus with 2 complete clockwise loops; excretory papilla massive................................................2.

2 Oesophageal bulb half the length of ventral sucker; cirrus-sac small, less than 1/5 of total body length ....... ........................................................................................................................................ F. amphitrite n. sp.

- Oesophageal bulb approximately the same length as ventral sucker; cirrus-sac large, approximately 1/5 of total body length ............................................................................................................... F. reburrus n. sp.