Triabin is a serine-protease inhibitor with a calycin fold [1].

1: Structure of the thrombin complex with triabin, a lipocalin-like exosite-binding inhibitor derived from a triatomine bug. Fuentes-Prior P, Noeske-Jungblut C, Donner P, Schleuning WD, Huber R, Bode W; Proc Natl Acad Sci U S A 1997;94:11845-11850. PMID:9342325