Archetype

Homology Weekly: Mandible Adductor Apodemes

The unusual hook-shaped mandible closer apodeme (left one in the pair) of species in the Odontomachini genus group (Anochetus emarginatus pictured here). Piece dissected out and cleared from all muscles (Scanning Electron Micrograph, Roberto Keller/AMNH)

Last August, before taking a break from blogging, I posted an impossible-to-answer trivia. It consisted of the image above depicting an unidentified mysterious skeletal piece (sclerite) in the shape of a hook, together with two key pieces of information: a) it is entirely internal; b) it comes in pairs. › Continue reading

Tags: Anochetus, Apodeme, Mandibles, Odontomachus, Trap-jaw ants

Homology Weekly: Mouthparts

Frontal part of the head in an Anochetus emarginatus worker, profile view (Scanning Electron Micrograph, Roberto Keller/AMNH)

This image shows the mouthparts of a trap-jaw ant in resting position. The only structures really visible are the prominent elongated mandibles (in yellow) that project forward. The rest of the pieces, laying immediately below, are retracted inside the preoral cavity.

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Tags: Anochetus emarginatus, Labium, Labrum, Mandibles, Maxillae, Mouthparts, Prognathous