Description
One of the specimens, AMZ 6698, is an adult female that lived in Zürich Zoo. It is represented by a virtually complete skeleton, but the skin was not preserved. According to Schwartz, the skeleton shows signs of osteoporosis and periodontitis (common in zoo animals), but not of other pathologies or abnormalities. The right teeth were removed before Schwartz studied the specimen. Schwartz selected this specimen as the holotype. The other specimen, AMZ-AS 1730, is a subadult male collected in the wild, of which only the skull, including the mandible (lower jaw), was preserved. The dentition includes both permanent and deciduous teeth. Specimens of Pseudopotto are at least superficially similar to pottos, but according to Schwartz, they differ in a number of traits. Among lorisids, Schwartz saw similarities between the false potto and true pottos as well as angwantibos and slow lorises (Nycticebus). The false potto is comparable in size to the smallest pottos, but falls within their range of metrical variation; small size is also seen in western pottos.
The tail, according to Schwartz, is longer than in the potto. He does not provide measurements of the tail of AMZ 6698 and notes that at least one vertebra is missing, but Sarmiento counted 11 caudal vertebrae in an illustration of AMZ 6698 and Groves counted at least 15. However, Sarmiento found that the number of caudal vertebrae ranges from 5 to 17, with an average of 11, in pottos. Relatively long tails are also common in the western form of the potto,, though according to Stump the tail of Pseudopotto is longer than any seen in pottos. The false potto allegedly has shorter spines on its cervical (neck) and first and second thoracic (chest) vertebrae, but Leon notes that this feature is also seen in western pottos. Schwartz writes that the false potto differs from pottos and angwantibos in lacking a bifid (two-tipped) spine on the second cervical vertebra, but Sarmiento found this feature in 3 out of 11 potto specimens he examined.
The ulnar styloid process (a projection on the ulna, one of the bones of the forearm, where it meets the wrist) is not as hooked as in other lorisids, according to Schwartz, which Groves suggests may indicate that the wrist is more mobile. Another alleged diagnostic feature is the presence of an entepicondylar foramen (an opening near the distal, or far, end of the bone) on the humerus (upper arm bone); however, Sarmiento found this feature in 4 out of 11 specimens, and on one side of a fifth, and Stump noted that the foramen occurred in specimens from across the potto's range.
The lacrimal fossa, a depression in the skull, is located on the upper surface of the skull in most lorisids, but Schwartz found that it was further to the back, inside the orbit (eye socket) in the false potto and the slow loris. Sarmiento found this feature in 3 out of 11 pottos examined. The coronoid process of the mandible is said to be more hooked in the false potto than in the potto and slow loris.
Other distinguishing features of the false potto are in the dentition. Sarmiento notes, however, that captive specimens may develop abnormalities in the teeth and that some dental characters Schwartz uses are quite variable, sometimes even from one side of the same individual to another. The third upper molar (M3) is more reduced in the false potto than in any other prosimian, according to Schwartz, but Leon notes that western pottos also have a relatively small M3. The third upper premolar (P3) is also reduced, resembling the condition in the fork-marked lemurs (Phaner). Stump writes that small P3s are also common in western pottos, although the false potto's P3 is shaped differently. Groves notes that P1 is quite long, another point of similarity with the fork-marked lemurs. The lower premolars are compressed laterally in Pseudopotto, the cusps on the cheekteeth are higher, and the cristid obliqua (a crest connected to the protoconid cusp) is at a relatively buccal position (in the direction of the cheeks).
In AMZ 6698, skull length is 59.30 mm (2.335 in) and length of the right humerus is 57.65 mm (2.27 in).
Read more about this topic: False Potto
Famous quotes containing the word description:
“God damnit, why must all those journalists be such sticklers for detail? Why, they’d hold you to an accurate description of the first time you ever made love, expecting you to remember the color of the room and the shape of the windows.”
—Lyndon Baines Johnson (1908–1973)
“The type of fig leaf which each culture employs to cover its social taboos offers a twofold description of its morality. It reveals that certain unacknowledged behavior exists and it suggests the form that such behavior takes.”
—Freda Adler (b. 1934)
“The next Augustan age will dawn on the other side of the Atlantic. There will, perhaps, be a Thucydides at Boston, a Xenophon at New York, and, in time, a Virgil at Mexico, and a Newton at Peru. At last, some curious traveller from Lima will visit England and give a description of the ruins of St Paul’s, like the editions of Balbec and Palmyra.”
—Horace Walpole (1717–1797)