[1] Species of Falcaustra have been known parasites that occur in the digestive tracts of fish, amphibians, and mammals.

[1] Falcaustra tannaensis is a nematode with a cylindrical body tapering anteriorly and posteriorly.

[1] Mouth opening is triangular, surrounded by 3 large lips, each with 2 papillai, amphidial pore at lateral edge of each subventral lip.

Cervical papillae slightly posterior to nerve ring, inconspicuous.

[1] It is also related to Falcaustra pelusios, a nematode that infects the gastrointestinal tract of turtles.