head shape
head heart-shaped
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The head of the soldier is somewhat heart-shaped with the evenly rounded posterolateral lobes bulging laterally and the head attenuating anteriorly. Used in Antkey to separate majors of Pheidole megacephala from other majors of other Pheidole.
head longer than wide
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head longer than wide (Pheidole minor)
head subquadrate
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The head is subquadrate, weakly longer than wide, and with a more flat posterior margin. Used in Antkey to separate the minor worker of Pheidole teneriffana from that of Pheidole fervens and Pheidole obscurithorax.
head shape not triangular
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The head shape is approximately ovoid or subrectangular, but never triangular. Used in Antkey to separate myrmicine genera.
head length weakly longer than head width
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The head length is weakly longer than head width. Used in Antkey to separate majors of Pheidole fervens from those of Pheidole teneriffana.
head shape triangular
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The head shape is approximately triangular, with the posterior margin distinctly broader than the anterior margin. Used in Antkey to separate myrmicine genera.
head shape quadrate
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The head length is approximately equal to the head with. Used in Antkey to separate the major worker of Pheidole teneriffana from that of Pheidole fervens.
head shape rectangular
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head shape square to rectangular (Pheidole major)
posterior margin convex
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The posterior margin of the head is strongly convex and arching strongly towards the eyes. Used in Antkey to separate the minor worker of Pheidole obscurithorax from Pheidole teneriffana (flat margin) and Pheidole fervens (weakly convex).
posterior margin convex
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The posterior margin of the head is distinctly convex. Used in Antkey to separate Plagiolepis alluaudi and Plagiolepis pygmaea from Plagiolepis exigua.