Révision des espèces de Cladochonus McCoy, 1847 (Tabulata) décrites dans le Frasnien de la Belgique par LECOMPTE en 1939 - Cladochonus frasniens de Belgique

The original material of the three species from the Frasnian of Belgium formerly assigned to the genus Cladochonus McCoy, 1847 by LECOMPTE (1939) has been revised. Two of these species are considered valid and maintained in the genus: C. robustus LECOMPTE, 1939 and C. maillieuxi LECOMPTE, 1939; C. brevicollis devonicus is for us a synonym of the last species. A microstructural study of C. robustus affords a useful comparison with the microstructure of typical Cladochonus from the Carboniferous. A systematical hierarchy of characters is proposed for the family Pyrgiidae DE FROMENTEL, 1861.