 The false potto generally resembles a small potto , but according to Schwartz it differs in having a longer tail , shorter spines on its neck and chest vertebrae , a smaller , less complex spine on the second neck vertebra , an entepicondylar foramen ( an opening in the humerus , or upper arm bone ) , a lacrimal fossa ( a depression in the skull ) that is located inside the eye socket , a smaller upper third premolar and molar , and higher @-@ crowned cheekteeth , among other traits . However , many of these traits are variable among pottos ; for example , one researcher found entepicondylar foramina in almost half of the specimens in his sample of pottos . 
