The genus Parapolycentropus, originally described for two species in 99 myo Burmese amber, is unique among Mecoptera for its long, thin proboscis and possession of just the mesothoracic pair of wings. A new series of 19 specimens with excellent preservation allows description and redescription of virtually all morphological details. Male terminalia are very similar to those of the Holarctic Recent family of “snow fleas,” the Boreidae. Thoracic sclerites are highly convergent with nematocerous Diptera in the expansion of the mesothorax and great reduction of the pro-and metathoraces. The metathoracic wing vestige appears to be just the tegula; axial sclerites are lost. Details of the pretarsal claws are described; in P. paraburmiticus Grimaldi and Rasnitsyn the outer claw of the meso- and metathoracic pretarsi is elongate and the inner claw reduced. The proboscis is comprised not of a labial tube and “pseudolabellum” (contra Ren et al, 2009), but is mostly maxillary in origin, with the outer valves probably being galeae and the central, serrated stylet probably the hypopharynx. Abdominal sternites are greatly reduced (more so in females), suggesting that the abdomen was distensible, a feature that is common in some fluid-feeding insects. The proboscis, claw, and sternite modifications indicate that Parapolycentropus fed on the hemolymph of small insects, not the blood of vertebrates.