137 Euura caeruleocarpus (Hartig, 1837)

Figs 135, 371

Nematus propinquus Dahlbom, 1835a: 25 . Nomen oblitum (Blank et al. 2009). Described based on larvae. Type material not located. Type locality: Sweden, Skåne, Lilla Raby near Lund. Synonymy with brachyacanthus by Thomson (1871).

Nematus caeruleocarpus Hartig, 1837: 187 . Nomen protectum (Blank et al. 2009).

Nematus sulcipes Hartig, 1837: 186–187 . Lectotype designated below. Synonymy by Kriechbaumer (1885).

Nematus brevispinis Förster, 1854a: 338–339 . Lectotype designated below. Synonymy by Kriechbaumer (1885).

Nematus brachyacanthus Thomson, 1863: 629 . Lectotype designated below. Synonymy by Cameron (1885).

Nematus insubricus Cobelli, 1892: 70–71 . Holotype ♀ (ROV), not examined. Type locality: Italy, Milano area . Synonymy by Dalla Torre (1894).

Diagnosis

The most similar species is E. vicina, which is best distinguished by its inner hind tibial spur being longer than the apical breadth of hind tibia (shorter in E. caeruleocarpus). Occasionally, northern specimens of E. caeruleocarpus have a bicoloured pterostigma (basally or externally black and apically or internally brown or yellowish). Genetically, E. villosa is very close to E. caeruleocarpus, but morphologically these species can be distinguished well:

– head and thorax with long hair; hind tibia completely and hind tarsus mainly yellow; pterostigma yellow .................................................................................................................................. E. villosa

– head and thorax with short hair; hind tibia black at tip and hind tarsus completely black; pterostigma black, rarely bicoloured ........................................................................................ E. caeruleocarpus .

Female: 8.0– 10.5 mm. Male: 7.5–8.5 mm.

Type material examined

Holotype Nematus caeruleocarpus

GERMANY – Niedersachsen • ♀; Harz; 51.8° N, 10.3° E; W. Saxesen leg.; ZSM, GBIF-GISHym3212.

Lectotype Nematus sulcipes, here designated GERMANY • ♀; ZSM, GBIF-GISHym3446.

Lectotype Nematus brevispinis, here designated

GERMANY – Nordrhein-Westfalen • ♂; Aachen area; 50.77° N, 6.09° E; ZSM, GBIF-GISHym 3210.

Lectotype Nematus brachyacanthus, here designated

SWEDEN • ♀; Skåne; MZLU, MZLU2017284.

Host plants

The main hosts are Salix spp., particularly S. fragilis L., S. purpurea L., S. triandra L. and S. viminalis L. (Miles 1936). Less frequently used are Populus spp. (e.g., Chambers 1947). Unconfirmed are Paeonia officinalis L., Delphinium sp. and Aquilegia sp. (Benson 1958a).

Genetics

COI

Based on 8 specimens, maximum within-species distance is 1.22% and the nearest neighbour, diverging by a minimum of 0.61%, is Euura villosa .

Nuclear

Based on 3 specimens, maximum within-species distance is 0.33% (0.33% based on haplotypes of individual females). The nearest neighbour, diverging by a minimum of 0.5%, is Euura villosa .

Distribution and material examined

Palaearctic. Specimens studied are from Austria, Bulgaria, Finland, Germany, Russia, and Sweden.