Tenthredo (Allantus) sturmii Klug, 1817: 116.
Macrophya pacifica F. Smith, 1874: 378.
Macrophya castanea Jakowlew, 1888: 373.
Encarsioneura frigida Mocsáry, 1909: 15–16.
Diagnosis. This species is similar to S. jucunda Mocsáry, but differs from the latter by the following: the microsculptures on the 2nd and 3rd abdominal tergites fine, matt; hairs on dorsum of head and of thorax black; malar space of male as long as the radius of a lateral ocellus, the 4th and 5th abdominal tergites blackish brown, the lobe of pennis narrow; malar space of female as long as the diameter of the middle ocellus, the 9th abdominal tergite yellowish brown, vein C almost entirely blackish brown.
Distribution. China (Heilongjiang (Wuying), Jilin (Mt. Changbai), Liaoning (Xinbin), Shanxi (Mt. Wutai), Hebei (Mt. Xiaowutai)), Japan (Hokkaido, southern Kuriles, Honshu, Kyushu), South Korea, Russian Far East (Primorskiy Kray; Sakhalin), Siberia, Europe.
Primary type examined. 1♀, lectotype (HNHM, here designated): “Sibirica or., Raddefka”; “ Encarsioneura frigida, det. Mocsáry” [red label]; “ Lectotype, Encarsioneura frigida Mocsáry, 1909, Des. Niu G, 2010”; “DEI-GISHym 1005”; “ Siobla sturmii (Klug, 1817), Det. Niu G, 2010”. 1♀, paralectotype (HNHM, here designated): “Sibirica or., Raddefka”; “ Encarsioneura frigida, det. Mocsáry” [red label]; “ Paralectotype, Encarsioneura frigida Mocsáry, 1909, Des. Niu G, 2010”; “DEI-GISHym 1000”; “ Siobla sturmii (Klug, 1817), Det. Niu G, 2010”. 1♂, paralectotype (HNHM, here designated): “Sibirica or., Raddefka”; “ Encarsioneura frigida, det. Mocsáry” [red label]; “ Paralectotype, Encarsioneura frigida Mocsáry, 1909, Des. Niu G, 2010”; “DEI-GISHym 1004”; “ Siobla sturmii (Klug, 1817), Det. Niu G, 2010”.
Remarks. No distinct difference was found between the types of Siobla frigida and S. sturmii. The former is treated as a junior synonym of the latter following Malaise (1931).