This family consists of PhTx insecticidal neurotoxins that are found in the venom of Brazilian, Phoneutria nigriventer. The venom of the Phoneutria nigrivente contains numerous neurotoxic polypeptides of 30-140 amino acids which exert a range of biological effects. While some of these neurotoxins are lethal to mice after intracerebroventricular injections, others are extremely toxic to insects of the orders Diptera and Dictyoptera but had much weaker toxic effects on mice [1].

1: Purification and amino acid sequence of a highly insecticidal toxin from the venom of the brazilian spider Phoneutria nigriventer which inhibits NMDA-evoked currents in rat hippocampal neurones. de Figueiredo SG, de Lima ME, Nascimento Cordeiro M, Diniz CR, Patten D, Halliwell RF, Gilroy J, Richardson M; Toxicon 2001;39:309-317. PMID:10978749