However recent morphological studies indicate they are better off as two separate species.

They will be placed in a tribe, possibly a new one, after further morphological study.

A number of morphological studies were carried out in the 20th century to better characterize the genus.

Jack Garrick, in his 1982 morphological study, did not place it close to any other member of the genus.

This hypothesis has been borne out by recent phylogenetic and morphological studies.

Believed to be among the most primitive of living tortoises, based on molecular and morphological studies.

She also contributed to development of morphological studies in botany during the early part of the 20th century.

A summary of data from a morphological study sheds light on the issue:

A 2012 morphological study interpreted them as subspecies instead.

Scarcity of careful morphological studies is the principal cause.