Anthonomus pedicularius (Linnaeus, 1758)
on Crataegus

Crataegus monogyna, Belgium, prov. Hainaut, Bailièvre, 8.v.2020 © Stéphane Claerebout

opened gall with larva

head of the larva
Crataegus monogyna, Dronten, two galled flowers in the inflorescence, 23.v.2010 © Arnold Grosscurt
opened gall with young pupa

Crataegus monogyna, Zwolle, 8.v.2018 © Arnold Grosscurt: opened gall with larva

larva
gall
Larvae and pupae in the flower buds. The buds remain closed, turn brown, often drop off.
host plants
Rosaceae, monophagous
Crataegus laevigata, monogyna.
That the species would live also on Pyrus, as Buhr writes, is not confirmed by Dieckmann.
references
Baviera & Caldara (2020a), Buhr (1964a), Colonnelli, Osella & Cornacchia (2011a), Delbol (2013a), Dieckmann (1968a, 1988a), Forbicioni, Abbazzi, Bellò ao (2019a), Knutelski (2001a), Lehmann & Hannover (2016a), Pedroni, dal Cortivo & Gatti (2017a), Podlussány (2007a), Redfern & Shirley (2011a), Rheinheimer & Hassler (2010a), Roskam (2009a), Tempère & Péricart (1989a), Tomasi (2014a), Ugarte San Vicente (2005a), Yunakov, Nazarenko, Filimonov & Volovnik (2018a).