<p>Plant-based green silver nanoparticles (AgNPs) have emerged as a sustainable, low-cost, and environmentally friendly approach in nanomedicine, industry, and agriculture. However, little is known about their environmental impact on aquatic organisms. Therefore, the current study aimed to assess the possible reproductive impairments and transgenerational effects of parental exposure to AgNPs synthesized from an aqueous extract of <i>Croton urucurana</i> leaves (G-AgNP1 = 0.05&#xa0;mg L⁻¹; G-AgNP2 = 0.14&#xa0;mg L⁻¹) in three generations (parental F0, and offspring F1 and F2) of the freshwater neotropical snail <i>Biomphalaria glabrata</i>. In addition, the possible effects of <i>C. urucurana</i> leaves aqueous extract (AqEx = 5.4&#xa0;mg L⁻¹) were also tested. The exposure of F0 to G-AgNP2 for 7&#xa0;days induced high mortality compared with the other groups, but with no significant impairment in their fecundity. A decrease in heart rate was observed for embryos from parental exposure to G-AgNP1 and AqEx for F1 and F2. While contrasting observations were made for G-AgNP2, with a reduction in the number of heartbeats per min for F1 and an increase for F2. Behavioral carry-over effects were detected after two generations. Overall, the current study demonstrates the reproductive toxicity and transgenerational effects of G-AgNPs on <i>B. glabrata</i>, indicating the relevance of evaluating transgenerational effects as a potential hazardous risk to gastropod populations.</p> Graphical Abstract <p></p>