Larvae of syrphid flies in the genus Microdon are so odd that they were originally described as molluscs.  The adults are more or less normal-looking flies, but larvae are predators of ant brood, living within the dark galleries of ant nests (in this case, with Linepithema oblongum).

Termas de Reyes, Jujuy, Argentina
Ectatomma tuberculatum workers tend to a membracid nymph.

Jatun Sacha reserve, Napo, Ecuador
Ectatomma tuberculatum workers tend to a membracid nymph.

Jatun Sacha reserve, Napo, Ecuador
Eciton burchellii army ant workers pull a termite from a rotting log.

Jatun Sacha reserve, Napo, Ecuador
Eciton burchellii workers pull a termite from a rotting log.

Jatun Sacha reserve, Napo, Ecuador
Eciton burchellii workers pull a termite from a rotting log.

Jatun Sacha reserve, Napo, Ecuador
Ectatomma tuberculatum workers tend to a membracid nymph.

Jatun Sacha reserve, Napo, Ecuador
Young house flies (Musca domestica) fill an inflatable structure- the ptilinum- with hemolymph to break free from the hard shell of the puparium. Once free, the ptilinum collapses back into the head.

Urbana, Illinois, USA
Young house flies (Musca domestica) fill an inflatable structure- the ptilinum- with hemolymph to break free from the hard shell of the puparium. Once free, the ptilinum collapses back into the head.

Urbana, Illinois, USA
Eciton burchellii army ant workers pull a termite from a rotting log.

Jatun Sacha reserve, Napo, Ecuador
Eciton burchellii army ant workers pull a termite from a rotting log.

Jatun Sacha reserve, Napo, Ecuador
Eciton burchellii army ant workers pull a termite from a rotting log.

Jatun Sacha reserve, Napo, Ecuador
See photo in original gallery.
all images and text © Alex Wild 2001-2013