Agglutinates human and mice erythrocytes. This activity can be specifically inhibited by mannosamine. This lectin shows very low toxicity in both mammals and insects. Expressed by the venom gland. The presence of a 'disulfide through disulfide knot' structurally defines this protein as a knottin. Exists in two forms, due to cis-trans isomerization at Gly-79-Pro-80. The trans isomer is the most abundant (75%). Belongs to the neurotoxin 10 (Hwtx-1) family. 51 (Hntx-8) subfamily. Hntx-8 sub-subfamily.