title: Lesueurillidae
text: # Lesueurillidae
  
  Lesueurillidae is an extinct family of paleozoic molluscs (gastropods?) with anisostrophically coiled shells of uncertain position (Gastropoda?) (according to the taxonomy of the Gastropoda by Bouchet & Rocroi, 2005).
  
  ## Taxonomy
  
  The taxonomy of the Gastropoda by Bouchet & Rocroi, 2005 categorizes Lesueurillidae in the superfamilia Euomphaloidea within the Paleozoic molluscs with anisostrophically coiled shells of uncertain position (Gastropoda?). This family has no subfamilies.
  
  ## Genera
  
  Genera in the family Lesueurillidae include
  
  * Eccyliopterus Remelé, 1888
     * Eccyliopterus abendanoni
     * Eccyliopterus alatus (Roemer, 1876) - type species
     * Eccyliopterus corniculum
     * Eccyliopterus declivis Koken, 1925 - synonym: Eccyliopterus spirillum.
     * Eccyliopterus incresens
     * Eccyliopterus ottawaensis
     * Eccyliopterus owenanus
     * Eccyliopterus regularis - synonym: Eccyliopterus princeps.
     * Eccyliopterus replicata
     * Eccyliopterus septiferus
     * Eccyliopterus tolli
     * Eccyliopterus vagrans
  * Lesueurilla Koken, 1898 - type genus of the family Lesueurillidae
     * Lesueurilla acutangulum
     * Lesueurilla bohemica
     * Lesueurilla beloitensis
     * Lesueurilla dilatata
     * Lesueurilla grandis
     * Lesueurilla helix
     * Lesueurilla infundibulum (Koken, 1896) - type species
     * Lesueurilla isabellaensis
     * Lesueurilla kushanensis
     * Lesueurilla louderbacki
     * Lesueurilla magna
     * Lesueurilla prima
     * Lesueurilla shirakii
     * Lesueurilla sinkiangensis
  * Mestoronema P. J. Wagner, 2002
     * Mestoronema bipatellare Koken, 1925 - type species
     * Mestoronema marginalis (Koken, 1925)
     * Mestoronema scotica (Longstaff, 1924)
  
  ## Description
  
  Fossils of family Lesueurillidae has sharp peripheral band and a short notch formed from deep V-shaped sinus. They are similar to Maclurites but they differ in early ontogenesis from them.
  
  