Insect toxin. Expressed by the venom gland. The presence of a 'disulfide through disulfide knot' structurally defines this protein as a knottin. Contains 4 disulfide bonds. Cleavage of the propeptide depends on the processing quadruplet motif (XXXR, with at least one of X being E). LD(50) is 50 ug/g in flesh fly larvae (S.carnaria). LD(50) is 50 ug/g in house crickets (Acheta domesticus). Belongs to the neurotoxin 19 (CSTX) family. 11 (latartoxin) subfamily.