Definition: A landform that extends above the surrounding terrain in a limited area. A mountain is generally steeper than a hill, but there is no universally accepted standard definition for the height of a mountain or a hill although a mountain usually has an identifiable summit and a local relief of more than 300m.
Known occurrences, collected specimens and observations of Clinidium (Arctoclinidium) apertum allegheniense R. T. & J. R. Bell 1975. View this species on GBIF