Updating the presence, distribution and chorology of Moroccan Dryopoidea (Coleoptera: Elmidae and Dryopidae)

Abstract

This work presents an updated list of water beetles of the Elmidae and Dryopidae occurring in Morocco. The study is based on an exhaustive review of literature (1914–2021) complemented with field and laboratory investigations on more than 2200 collected individuals between 1997 and 2019. As a result, 30 species belonging to nine genera of Elmidae and Dryopidae are listed with their distribution in Morocco and North Africa. From the 30 species, Elmidae are represented by 21 species and seven genera, whereas Dryopidae are represented by nine species and only two genera. A chorological analysis shows that the Elmidae and Dryopidae from Morocco are essentially Mediterranean (60%), with a very high prevalence of endemics in the broadest sense (77.78%) within this group, whilst those Palearctic species (33.33%) or Afrotropical-Mediterranean (6.67%) are clearly less represented. This chorotype pattern is notably different to that observed in other aquatic beetle families in the same study area, where the percentage of endemic species was much lower. Moroccan Dryopoidea include seven endemic species exclusive to Morocco, six Maghrebian and one Ibero-Maghrebian species.