Diclonius

Diclonius (meaning "double sprout") is an extinct genus of hadrosaurid dinosaur from the Late Cretaceous Period. The genus is based solely on the remains of fossilized teeth. Its fossils have been found in North America. The name is in reference to the tooth roots, which are doubled and in contrast to Monoclonius ("single stem"), which Cope named in the same paper.

The type species, Diclonius pentagonus, is a nomen nudum discovered by Cope in 1876. Other formally undescribed species include D. calamarius and D. perangulatus. A "fourth" species has been reclassified as Anatotitan. They are all tooth taxa, known only from teeth and one jaw.

Although Cope referred several other batches of teeth to the genus, under several species, the name is considered a nomen dubium.

Species
Type:
 * D. pentagonus Cope, 1876 (type); fragmentary dentary with teeth

Other Species:
 * D. calamarius Cope, 1876; teeth
 * D. mirabilis (Leidy, 1856) Cope, 1883; included in part with Trachodon mirabilis and Anatotitan copei
 * D. perangulatus Cope, 1876; teeth

*Note: Diclonius mirabilis is actually the assignment of Trachodon mirabilis to Diclonius by Cope (1883).