Table 5. Meristic data of Potamotrygon sp. (río Madre de Díos, Peru). SD = Standard deviation.
Counts n Range Mean SD
Precaudal vertebrae 5 27-32 29.4 1.8
Caudal vertebrae 5 92-103 98.2 4.3
Total vertebrae 5 123-132 127.8 4.1
Diplospondylous vertebrae 4 92-100 96.0 3.7
Upper tooth rows 4 36-44 39.5 3.3
Lower tooth rows 4 33-45 37.5 5.3
Propterygial radials 5 42-44 42.4 0.9
Mesopterygial radials 5 14-15 13.8 0.4
Metapterygial radials 5 34-36 35.0 1.2
Total pectoral radials 5 90-93 91.2 1.3
Pelvic radials (male) 5 21-22 21.2 0.4