title: Melanopsis letourneuxi
text: # Melanopsis letourneuxi
  
  Melanopsis letourneuxi is a species of freshwater gastropod endemic to streams in coastal Morocco and Algeria.
  
  ## Distribution, ecology and threats
  
  Melanopsis letourneuxi is found almost exclusively in relatively shallow medium-sized streams with stony substrates, rarely occurring in stagnant sources. The species had historically been reported from several localities in north Africa, including a site in Algeria or (disputedly) Morocco - "in the source and the river Moulouya, west of Maghnia" from which it has not been documented recently- and two confirmed adjacent Moroccan sites -Berguent and Ras el Ain at Aïn Beni Mathar - in which it is exceedingly rare. Remaining populations are threatened by water abstraction, pollution, and shell-collecting.
  
  ## Populations
  
  Historically, several varieties (excluding the nominal var.) had been identified by Pallary and Bourguignat, including:
  
  * † Melanopsis letourneuxi var. semesa
  * Melanopsis letourneuxi var. magna (Berguent at Aïn Beni Mathar)*
  * Melanopsis letourneuxi var. minor (Ras el Aïn at Aïn Beni Mathar)*
  * Melanopsis letourneuxi var. emaciata (Berguent at Aïn Beni Mathar)
  * Melanopsis letourneuxi var. mattarica (Ras el Aïn at Aïn Beni Mathar)
  
  † Denotes that the variety is not mentioned by the nomenclator of Neubauer 2016
  
  *Denotes that the variety is considered invalid by the nomenclator of Neubauer 2016
  
  