Euura polaris
Creators: name: Prous, Marko
name: Liston, Andrew
name: Monckton, Spencer K.
name: Kramp, Katja
name: Vårdal, Hege
name: Vikberg, Veli
name: Heibo, Erik
name: Mutanen, Marko
Publisher: name: Zenodo
Year: 2025
Subjects: Biodiversity
Taxonomy
Animalia
Arthropoda
Insecta
Hymenoptera
Tenthredinidae
Euura
Euura polaris

description: 126 Euura polaris (Holmgren, 1883)
Figs 132, 356
Nematus polaris Holmgren, 1883: 143, pl. 1 fig. 1. Lectotype designated below.
Pteronus shumagensis Kincaid, 1900: 357. Syntype ♀ (USNMENT00778206, USNM, http://n 2t.net/ ark:/65665/35ff0e035-a05a-4e67-952c-f19e4292e418), not examined. Type locality: USA, Alaska, East Aleutians, Popof Island. Synonymy by Benson (1961a), but possibly it is E. lienterica or some other species in the E. flavescens group.
Pontania islandica Kincaid, 1900: 355. Syntype ♀ (USNMENT00778189, USNM, http://n 2t.net/ ark:/65665/35c79c1ef-402a-4e80-b738-6153f2e0f2e8), labelled as lectotype by J.-P. Kopelke, but designation not published; not examined. Type locality: USA, Alaska, East Aleutians, Popof Island. Synonymy by Benson (1961a). It does seem to belong to the E. bipartita group.
Amauronematus polaris ab. pleuralis Lindqvist, 1944b: 20. Type not found. Type locality: Finland, Inari, Ivalo. Perhaps not E. polaris. Unavailable name, because infrasubspecific.
Diagnosis
Most similar to E. leptostigma, E. polepso sp. nov., and some specimens of E. leucopyga. Often, its rather broad and square-shaped valvula 3 in dorsal view (like in some E. leucopyga) distinguishes E. polaris from E. leptostigma and E. polepso which tend to have a narrower valvula 3. The smooth mesepisternum may help to distinguish E. polaris from E. polepso (always slightly matt?). The combination of triangular serrulae, small cypsellae, and gradually narrowing lancet of E. polaris help to distinguish it from lancets of E. polepso (large cypsellae) and E. leucopyga (somewhat flatter serrulae and more abruptly narrowing lancet). Lancets of E. leptostigma are rather similar to E. polaris, but may differ in overall shape and are perhaps (usually?) larger. The males are not clearly distinguishable from E. leptostigma, E. leucopyga, E. parviserrata, E. sulciceps, and E. polepso.
Type material examined
Lectotype Nematus polaris, here designated
RUSSIA – Novaja Zemlya • ♀; Matotschkin Scharr [Matochkin Strait]; 73.3° N, 55.6° E; 1875; NHRS, NHRS-HEVA000006445.
Host plants
Unknown. Lindqvist (1944b) reported Salix spp.,but this apparently refers to E.leucopyga (ab. leucopyga) in southern Finland, while E. polaris is known only from (sub)arctic habitats.
Genetics
COI
Based on 8 specimens, maximum within-species distance is 2.89% and the nearest neighbours, diverging by a minimum of 0%, are Euura leptostigma, E. sulciceps, and E. fuscarima.
Nuclear
Based on 8 specimens, maximum within-species distance is 0.66% (0.85% based on haplotypes of individual females). The nearest neighbour, diverging by a minimum of 0.26%, is Euura leptostigma.
Distribution and material examined
Holarctic. Specimens studied are from Finland, Norway, and Russia. Nearctic records, although likely, need confirmation.
description: Published as part of Prous, Marko, Liston, Andrew, Monckton, Spencer K., Kramp, Katja, Vårdal, Hege, Vikberg, Veli, Heibo, Erik & Mutanen, Marko, 2025, West Palaearctic species of Euura Newman, 1837 (Hymenoptera, Tenthredinidae), pp. 1-377 in European Journal of Taxonomy 977 on pages 71-72, DOI: 10.5852/ejt.2025.977.2799, http://zenodo.org/record/15019574