Euura excisa ( Thomson, 1863 )

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), European Journal of Taxonomy 977, pp. 1-377 : 54-55

110 Euura excisa ( Thomson, 1863)

Fig. 116

Nematus excisus Thomson, 1863: 628 . Lectotype designated below.

Lygaeonematus strandi Konow, 1901a: 92 . Lectotype designated below. Synonymy by Lindqvist (1952).

Diagnosis

Mostly black, labrum and partly clypeus pale; head behind eyes sometimes pale; tegula pale;pterostigma pale; valvifer 2, hypopygium posteriorly, tergum 9 partly, and tergum 10 pale; metafemur apically pale; metatibia pale; hind tarsus pale or brown; claws with small subapical tooth, mesepisternum (usually?) matt, valvula 3 in dorsal view elongate, thin and gradually tapering.

Most closely related species are E. declinata and E. scotonota (character states in parentheses), from which it differs by having claws with small subapical tooth (usually bifid or with large subapical tooth) and matt mesepisternum (smooth). Additional characters like its mostly black body, pale pterostigma and tibiae enable it to be separated from all other species of Euura relatively easily.

Male unknown, but penis valve could be similar to the closely related E. declinata and E. scotonota .

Type material examined

Lectotype Nematus excisus , here designated

SWEDEN • ♀; Norlandia [Lapland, probably Sweden]; C.H. Boheman leg.; MZLU, MZLU2017274 .

Lectotype Lygaeonematus strandi , here designated

NORWAY – Nordland • ♀; Hadsel; 68.5° N, 15.0° E; E. Strand leg.; SDEI, GBIF-GISHym3880 .

Host plants

Bistorta vivipara (L.) Delarbre.

Genetics

COI

Based on 5 specimens, maximum within-species distance is 1.41% and the nearest neighbour, diverging by a minimum of 1.22%, is Euura fuscomaculata .

Nuclear

Based on 5 specimens, maximum within-species distance is 0.15% (0.34% based on haplotypes of individual females). The nearest neighbour, diverging by a minimum of 0.71%, is Euura scotonota .

Distribution and material examined

Holarctic. Specimens studied are from Finland, Greenland (only genetics), Norway, and Sweden.

Figures

Figs 114–117. Lancets of Euura Newman, 1837. 114. mimus (Konow, 1903) DEI-GISHym20610. 115. declinata (Förster, 1854) OR.408.116. excisa (Thomson, 1863) DEI-GISHym19635.117. scotonota (Förster, 1854) DEI-GISHym17157.