Mesolicaphrium


Mesolicaphrium is a genus of extinct litoptern from the late middle Miocene of southern Colombia. It was named in 2020 by Andrew McGrath and colleagues, for the species previously classified as Prolicaphrium sanalfonensis from the La Victoria and Villavieja Formations of the Honda Group, Colombia. The type species is M. sanalfonense, known from the jaw symphysis and two right mandibular rami, and teeth. Mesolicaphrium is derived from the similarity to the names Prolicaphrium and Neolicaphrium, and being in between both taxa in age. The taxon was recovered in a phylogenetic analysis as the sister taxon of Diplasiotherium, closely related to Olisanophus.

Description

The deciduous mandibular premolars of M. sanalfonense all have two roots. The dp1 is smaller mesiodistally and labiolingually than the others. The dp2 differs from the dp1 in having its paraconid attach to the paralophid near the tooth's mesial end and in the greater size of its metaconid spur, in addition to the former tooth being larger in overall size. The dp3 is molariform, exhibiting a double crescent morphology. The dp4 differs from the dp3 in having a paraconid that is smaller and that attaches to the mesiolingual end of the paracristid, as well as in having a smaller ectostylid.