I have been to Malta in the end of March 2016. Although time was limited during this two-day trip, I also searched once for H. algirus in the so-called bend over park (weird place, indeed...). A snake was caught within a short time, but unfortunately it was the "wrong" species.
Hierophis viridiflavus from the H. algirus site.Could it be the case that since the last confirmation of the existence of H. algirus on Malta (2007?), this introduced species has been replaced by the native H. viridiflavus?