Key to Myrcidris Species

This key to species of Myrcidris, based on the worker caste, has been provided by Phil Ward.

• Larger species, with relatively broad head; HW 0.49-0.61, CI 0.75-0.79 (n = 14); Amazonas, Brazil => Myrcidris epicharis
• Smaller species, with more elongate head; HW 0.39-0.42, CI 0.64-0.66 (n = 3); Guyana => undescribed species

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Measurements and indices used:

• HW - maximum width of head, including the eyes (in mm)
• HL - length of head, measured from the anterior extremity of the clypeus to the midpoint of a line drawn across the posterior margin of the head (in mm)
• CI - cephalic index = HW/HL