 I. anglicus , described by Friedrich Holl in 1829 , is the original type species of Iguanodon , but , as discussed above , was replaced by I. bernissartensis . In the past , it has been spelled as I. <unk> ( <unk> and <unk> , 1993 ) and I. <unk> ( Holl , 1829 <unk> . <unk> , 1850 ) . It is known from teeth from the middle Valanginian @-@ age Lower Cretaceous <unk> Clay Formation ) of <unk> , West Sussex , England . It is currently classified in the genus Therosaurus as T. anglicus . 
