Hydrelia gracilipennis

{{Short description|Species of moth}}

{{Speciesbox

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| taxon = Hydrelia gracilipennis

| authority = Inoue, 1982{{cite web |last=Yu |first=Dicky Sick Ki |url=http://www.taxapad.com/local.php?taxonidLC=82875928 |title=Hydrelia gracilipennis Inoue 1982 |website=Home of Ichneumonoidea |publisher=Taxapad |archive-url=https://web.archive.org/web/20160326231947/http://www.taxapad.com/local.php?taxonidLC=82875928 |archive-date=March 26, 2016}}

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Hydrelia gracilipennis is a moth in the family Geometridae first described by Hiroshi Inoue in 1982. It is found in Japan.{{cite journal |last1=Xue |first1=Dayong |last2=Scoble |first2=Malcolm J. |date=June 27, 2002 |url=https://www.biodiversitylibrary.org/page/40870918#page/79/mode/1up |title=A review of the genera associated with the tribe Asthenini (Lepidoptera: Geometridae: Larentiinae) |journal=Bulletin of the Natural History Museum |series=Entomology Series |volume=71 |issue=1 |pages=77–133 |doi=10.1017/S0968045402000044}}

The wingspan is 15–18 mm.[http://www.jpmoth.org/Geometridae/Larentiinae/Hydrelia_gracilipennis.html Japanese Moths]