Contact of prefrontal with supralabials
Of the 243 specimens examined, 147 (60.5%) have the prefrontal separated from the labials on each side. Of the remaining 96 specimens, 53 (21.8% of the 243) have the prefrontals in contact with the second labial on each side; five other variations of this characteristic were observed ([Table 2]).
Table 2. Variation in Contact of the Prefrontals and the Labials in 243 Specimens of Tantilla gracilis.
| Characteristic | Number of specimens | Per cent of occurrence |
|---|---|---|
| No contact | 147 | 60.5 |
| Contact of prefrontal with second labial on right | 26 | 10.7 |
| Contact of prefrontal with second labial on left | 10 | 4.1 |
| Contact of prefrontal with each second labial | 53 | 21.8 |
| Contact of prefrontals with labial two on left and labial three on right | 1 | 0.4 |
| Contact of prefrontals with labial three on left and labial two on right | 3 | 1.2 |
| Contact of prefrontals with labial two on left and labials two and three on right | 3 | 1.2 |
The specimen having the prefrontal in contact with labial 2 on the left and labial 3 on the right has seven supralabials on the right, the extra labial being added anterior to the eye. In two of the three specimens with the prefrontals in contact with labial 3 on the left and labial 2 on the right, the preoculars and prefrontals are fused on each side; the third specimen has each preocular reduced to a small vertical sliver. Of the three specimens having the prefrontals in contact with labial 2 on the left and labials 2 and 3 on the right, two are typical with respect to other characteristics that might result in this atypical condition, but one has the prefrontals and preoculars fused.