Metopobactrus prominulus (O. Pickard-Cambridge, 1872). a: male from Ordesa, lateral habitus, scale = 0.2 mm; b: male from Picos de Europa, lateral habitus, scale = 0.2 mm; c: female from Picos de Europa, dorsal habitus, scale = 0.5 mm; d: male from Ordesa, left palp, retrolateral, scale = 0.1 mm; d: male from Ordesa, left palp, prolateral, scale = 0.1 mm; e: male from Picos de Europa, left tibia, prolateral, scale = 0.1 mm; f: male from Picos de Europa, left tibia, retrolateral, scale = 0.1 mm; g: female from Picos de Europa, epigynum, ventral, scale = 0.1 mm.