Tongue anomaly is called as:

A completely cleft or bifid tongue is a rare condition that is apparently due to lack of merging of the lateral lingual swellings of this organ. A partially cleft tongue is considerably more common and is manifested simply as a deep groove in the midline of the dorsal surface. The partial cleft results because of incomplete merging and failure of groove obliteration by underlying mesenchymal proliferation. Interestingly, it is often found as one feature of the oral-facial-digital syndrome in association with thick, fibrous bands in the lower anterior mucobuccal fold eliminating the sulcus and with clefting of the hypoplastic mandibular alveolar process.  Ref:Shafer’s Ed 7th Pg 26