thermonema lapsum thermonema lapsum thermonema lapsum is a gram-negative and thermophilic bacterium from the genus of thermonema which has been isolated from a hot spring in rotorua in new zealand.homospermidine and homospermine are the major polyamines of thermonema lapsum thermonema lapsum scientific classification domain: bacteria phylum: bacteroidota class: cytophagia order: cytophagales family: thermonemataceae genus: thermonema species: t. lapsum binomial name thermonema lapsumhudson et al. 1989 type strain 23/9, atcc 43542, dsm 5718, ncimb 13422