The protocone and the metaconule
are oppressed to form a contiguous proto-metaconule complex.
M1 subtriangular, with well-developed metaconule
united to the protocone, lingual part with a tendency to reduction.
is present posterior to the protocone.
1 (basalmost artiodactyls [paraphyletic]: diacodexid, primitive [unassigned, some dichobunine] dichobunid dichobunoids): Ml-3 (Ms) bunodont, triangular; metaconule
unenlarged; no hypocone (Old World [OW] origin).
(SDSM 82103)--Wang's (5) diagnosis for the subfamily is based on cranial characters and dental characters of P4, M1, and m1 which cannot be used to determine the identification of the tooth and "the subfamily is mainly defined by its lack of synapomorphics for the other two subfamilies." The lack of the paraconule and metaconule
suggest a primitive morphology and support the assignment to the Hesperocyoninae.
Bailit 1980 The metaconule
: a morphological and familial analysis of a molar cusp in humans.
is pyramidal in shape with a moderately developed preme tacrista that is mesiolingually directed to join the slight lingual cingulum between protocone and metaconule
There is no clear cut demarcation between the metaconule
and the protocone.
The metacone is partially broken, and connected to the metaconule
by a narrow crest.
The tooth can be described as follows: ectoloph is typically W-shaped; hypocone is absent but a postprotocrista extends posteriad from the metaconule
as a curved sloping ridge with a small talon formed by its base.