Professor (Associated) Errol Hassan was born in 1935 in Kukla Village of Baf town in Cyprus. After his Primary and Secondary education in Cyprus, he graduated from Agricultural Faculty of Ankara University in 1960. He completed his PhD. thesis on Forestry Entomology with the highest academic achievement, Magna Cum Laude at George-August University, Germany, in 1966. He worked as Adjunct Associate Professor in The University of Queensland, Gatton Campus, Australia since 1973. Professor Hassan retired in 2000 when in Queensland University. He was asked to continue to give lectures in the university with Honorary degree. He provided many lectures to undergraduate and postgraduate students, supervised thesis of many M.S. and Ph.D. candidates. He was also doing consulting at both national and international levels and was developing training workshops in applied entomology. He published many articles on Plant Extracts, Essential Oils, Biopesticides, and Integrated Pest Management, and received 608 citations. Professor Hassan named a parasitoid species new for science with the name of his wife in memory of their marriage for more than 50 years. He had a good relationship with Turkish colleagues, and contributed many of them with his scientific experience. He passed peacefully on June 27, 2022. He touched the lives of so many people in Turkey, and will be remembered forever. Editor-in-Chief note: Professor Errol Hassan started to contribute to Editorial Board of Trakya University Journal of Natural Sciences since 13 November 2017 in the fields of Entomology and Agriculture. He read all submitted manuscripts in these fields with an incredible devotion and without a sign of offence, and provided criticisms to improve all. When we made a contact with Professor Errol Hassan to propose him to become the guest editor of the special issue of “Biodiversity of Insects”, he replied in the affirmative with a kind manner. He continued to contribute all submissions both in the Editorial Board of the journal and as the guest editor role of the special issue until May 2022. Upon his sickness and the hospitalization process, Prof. Dr. Kadri KIRAN, as the editor-in-chief of the journal, undertook all assigned work load of him and did his best to continue in the scientific line Professor Errol Hassan adopted. We will never forget advices, contributions on the published manuscripts and academic politeness of Professor Errol Hassan, all which he never conceded with the aim of improving the scientific quality of the journal.