Info taken from Bugguide:
The larvæ of many sawfly species resemble the caterpillars of butterflies and moths, but can be distinguished by the fact that they never have fewer then six pairs of prolegs ( Lepidopteran caterpillars never have more then 5 pairs ). Other sawfly larvæ are legless and may even be slimy to the touch, leading early entomologist to call them "slug worms".
The adult sawflies have four-wing and may closely resemble other hymenopterans, but lack the characteristic "wasp-waist" between the thorax and abdomen. Females typically have conspicuous ovipositors that may look fearsome, but these are never used as stingers.
Adult sawflies typically feed on nectar or pollen and most sawfly larvæ feed openly on leaves. Some larvæ that are legless bore into the stems or mine into the leaf tissue. A few sawfly species have been reported to be carnivorous or parasitic.
And pics will be coming! =)