TITLE: GCN CIRCULAR NUMBER: 36056 SUBJECT: EP240408a: BOOTES-6/DPRT optical upper limit DATE: 24/04/09 23:00:10 GMT FROM: Alberto Castro-Tirado at Inst.de Astro. de Andalucia I. Perez-Garcia, E. Fernandez-Garcia, M.D. Caballero-Garcia, R. Sanchez-Ramirez, S. Guziy, S.-Y. Wu and A. J. Castro-Tirado (IAA-CSIC, Granada), P. J. Meintjes and H. J. van Heerden (UFS, South Africa), A. Martin-Carrillo and L. Hanlon (UCD, Ireland), M. Gritsevich (Univ. of Helsinki) and C. J. Perez del Pulgar (UMA, Malaga), on behalf of a larger collaboration, report: Following the detection of the fast X-ray transient EP240408a by the Einstein Probe (Hu et al. GCNC 36053), the BOOTES-6/DPRT 0.6m robotic telescope at Boyden Observatory in Maselspoort (South Africa) observed the fast X-ray transient location starting on Apr 9, 18:54 UT (~ 25 h after trigger) in different optical bands. No new optical source is detected on the co-added images (clear-filter) within the EP/WXT error box down to 20.5 mag. We thank the staff at Boyden Observatory for their excellent support.