This research article published by MDPI, 2020This paper reports on farmers’ knowledge, perceptions, and reactions towards the African apefly (Spalgis lemolea lemolea), which appeared to be associated with some vegetables in some locations in Tanzania. Information was obtained from a sample of 100 key respondents using a semi-structured questionnaire and from focus groups selected from key locations in five districts in the country with histories with the African apefly. Acute and sub-acute toxicity tests of the African apefly were performed on female Swiss hybrid mice (Mus musculus) to assess whether or not the African apefly was toxic to mammals. The mice were exposed to increasing apefly meal concentrations in acute and sub-acute tests, and signs of toxicity were observed for 14 and 28 days, respectively. Blood samples were collected by cardiac puncture for hematological and biochemical analysis. Gross and microscopic examinations of the internal organs were done. The survey results showed that 92.1% of the respondents perceived the African apefly as poisonous and had stopped consuming the vegetables associated with it. In the toxicity tests, however, no death or toxic signs were displayed, and there was no significant difference between the control and treated mice in weight, hematological parameters, and histo-pathological examination results. These findings strongly indicate that, despite the negative perception by farmers regarding the African apefly, it is not poisonous. However, further studies on how farmers can be trained to have a positive perception of the African apefly and how the insect can be conserved for further research regarding its role in Tanzania are recommended.