Comparative immunological study of the snail Physella acuta (Hygrophila, Pulmonata) reveals shared and unique aspects of gastropod immunobiology.

•Analysis of Physella acuta immune genes compliments comparative immunology.•Transcriptomics revealed taxon-specific differences in immune capability.•Interaction of P. acuta with E. paraenseireveals that the FREP biology of physid snails differs from planorbid snails.•Limited arsenal of antimicrosbial peptides is common to planorbid and physid snails.•Strategic use of organisms for comparative immunology facilitates questions on the evolution of immunity within metazoans.