
1) Sawfly
Found on
https://www.crosswordclues.com/clue/horntail

Female horntails lay their eggs in trees. The larvae bore into the wood and live in the tree for up to two years, possibly more. They typically migrate to just under the bark before pupation. The spiral groove on the ovipositor is visible on the photograph but not easily to the naked eye. The smaller horntail (Sirex noctilio) is only about half th...
Found on
http://en.wikipedia.org/wiki/Horntail

• (n.) Any one of family (Uroceridae) of large hymenopterous insects, allied to the sawflies. The larvae bore in the wood of trees. So called from the long, stout ovipositors of the females.
Found on
http://thinkexist.com/dictionary/meaning/horntail/

any of about 85 species of solitary (nonsocial), primitive wasps (order Hymenoptera), classified in five different genera, that are moderately large, ...
Found on
http://www.britannica.com/eb/a-z/h/70
Horn'tail` noun (Zoology) Any one of family (
Uroceridæ ) of large hymenopterous insects, allied to the sawflies. The larvæ bore in the wood of trees. So called from the long, stout ovipositors of the females.
Found on
http://www.encyclo.co.uk/webster/H/62

any of various wasplike insects of the family Siricidae, the females of which have a hornlike ovipositor.
Found on
https://www.infoplease.com/dictionary/horntail
No exact match found.