no small teeth anterior to spines

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Imaging technique: 

The head anterior to the posterolateral spines is smooth and not interrupted by a pair of small teeth or blunt angles. Used in Antkey to separate Atta cephalotes from Atta sexdens. This is a variable character, and should be used with caution until its usefulness is confirmed.

Eli Sarnat
Taxonomic name: 
Scratchpads developed and conceived by (alphabetical): Ed Baker, Katherine Bouton Alice Heaton Dimitris Koureas, Laurence Livermore, Dave Roberts, Simon Rycroft, Ben Scott, Vince Smith