Pristiphora ruficornis (Olivier, 1811)

Prous, Marko, Vikberg, Veli, Liston, Andrew & Kramp, Katja, 2016, North-Western Palaearctic species of the Pristiphora ruficornis group (Hymenoptera, Tenthredinidae), Journal of Hymenoptera Research 51, pp. 1-54 : 32

Pristiphora ruficornis (Olivier, 1811)

Nematus ruficornis Olivier in Olivier and Manuel 1811: 167. Syntype(s) possibly in MNHN, not examined. Type locality: near Paris, France.

Pristiphora testaceicornis Serville, 1823: 75. Syntype(s) ♂ not found in MNHN ( Lacourt 2000). Type locality: Paris, France.

Pristiphora testaceicornis Lepeletier, 1823: 60. Primary homonym of Pristiphora testaceicornis Serville, 1823 [= Pristiphora (Pristiphora) ruficornis (Olivier, 1811)]. Syntype(s) ♂ not found in MNHN ( Lacourt 2000). Type locality: Paris, France.

Nematus (Nematus) robustellus Dahlbom, 1835b: 9. Type(s) not available. Nomen nudum.

Nematus fraxini Hartig, 1837: 204. Lectotype ♀ (GBIF-GISHym3285; here designated) in ZSM, examined. Type locality: Harz, Germany.

Nematus testaceicornis Jacobs, 1884: XXIII-XXIV. Syntype(s) ♀ possibly in IRSNB, not examined. Type locality: near Brussels, Belgium.

Nematus (Pristiphora) ruficornis var. integer Hellén, 1948: 116, syn. n. Primary homonym of Nematus integer Say, 1836. Holotype ♀ (http://id.luomus.fi/GL.5212) in MZH, examined. Type locality: Hammaslahti, North Karelia, Finland.

Similar species.

The most similar species is P. melanocarpa , which has darker antennae compared to P. ruficornis . Females have a distinctly paler ventral side of antennae (Fig. 25 ), while antennae in P. melanocarpa are uniformly black (Fig. 24 ) or have only a slightly paler ventral side. Males of P. ruficornis also have generally paler antennae than in P. melanocarpa (Fig. 26 ), but penis valves should be studied to distinguish them from P. melanocarpa specimens having conspicuously pale antennae. Ventro-apical spine of penis valve (Figs 79 , 81 ) bends more gradually (forming a half circle) and is usually broader than in P. melanocarpa (Figs 80 , 82 ).

Genetic data.

Based on COI barcode sequences, specimens of P. ruficornis are divided between two BIN clusters (BOLD:ACZ4465 and BOLD:ACZ4466) that also include P. melanocarpa (Fig. 1 ). Minimal distance between these two clusters is only 1.13%. Nuclear TPI sequences do not support separation of P. ruficornis from P. melanocarpa either (Fig. 2 ). The single sequenced male would be identical to one of the heterozygous P. melanocarpa females when ambiguous positions due heterozygosity are excluded. Examination of all the 14 heterozygous sites (double peaks in chromatograms) in this P. melanocarpa specimen revealed that all of them include also the nucleotide found in P. ruficornis , possibly indicating haplotype sharing between these two taxa.

Host plants.

Betula pubescens Ehrh. ssp. czerepanovii (N. I. Orlova) Hämet-Ahti (rearings and ex ovo rearing experiments by VV).

Distribution and material examined.

Western Palaearctic. Specimens studied are from Finland, Germany, Portugal, and Sweden.

Figures

Figure 1. Maximum likelihood tree of Pristiphora ruficornis group based on cytochrome oxidase subunit I (COI) sequences (1078 bp). Specimens that had at least the full barcode sequence (658 bp) were included in the analysis. Branches with multiple specimen identification labels represent identical sequences, only one of which was used in the analysis. Numbers on the nodes show approximate likelihood-ratio test (aLRT) support values and bootstrap proportions (%, BP). Support values for weakly supported branches (aLRT <0.9 and / or BP <70) are not shown. The inset shows the tree with outgroup species. The scale bar shows the number of estimated substitutions per nucleotide position. An asterisk (*) indicates the specimens that we have not studied. AUT, Austria; CAN, Canada; CHN, China; DEU, Germany; ESP, Spain; EST, Estonia; FIN, Finland; FRA, France; GBR, United Kingdom; ITA, Italy; MAR, Morocco; NOR, Norway; PRT, Portugal; SWE, Sweden; USA, United States of America. NUMTs?, possible nuclear mitochondrial pseudogenes.

Figure 2. Maximum likelihood tree of Pristiphora ruficornis group based on triose-phosphate isomerase (TPI) sequences (alignment length 842 bp). Branches with multiple specimen identification labels represent identical sequences, only one of which was used in the analysis. Numbers on the nodes show approximate likelihood-ratio test (aLRT) support values and bootstrap proportions (%, BP). Support values for weakly supported branches (aLRT <0.9 and / or BP <70) are not shown. The scale bar shows the number of estimated substitutions per nucleotide position.

Figures 18 - 36. 18 P. albitibia DEI-GISHym 31514, thorax in lateral view 19 P. luteipes DEI-GISHym 80038, thorax in lateral view 20 P. astragali holotype, thorax in lateral view 21 P. leucopus DEI-GISHym 31556, lateral 22 P. leucopus DEI-GISHym 4989, lateral 23 P. luteipes DEI-GISHym 80038, lateral 24 P. luteipes DEI-GISHym 80038, flagellum 25 P. ruficornis DEI-GISHym 31185, flagellum 26 P. armata DEI-GISHym 11092 27 P. subopaca holotype, pterostigma (arrow) 28 P. opaca holotype, pterostigma (arrow) 29 P. ruficornis DEI-GISHym 31185, pterostigma (arrow) 30 P. appendiculata DEI-GISHym 31500, claw 31 P. opaca holotype, claw 32 P. subopaca holotype, claw 33 P. armata DEI-GISHym 11554, claw 34 P. bifida DEI-GISHym 31507, claw 35 P. frigida NHRS-HEVA 000005006, flagellum with barely visible stout black setae (arrows) 36 P. pusilla DEI-GISHym 80050, flagellum with clearly visible stout black setae.

Figures 77 - 86. Penis valves of Pristiphora ruficornis group. 77 P. appendiculata DEI-GISHym 31555 78 P. albitibia DEI-GISHym 20956 79 P. ruficornis PR. 462 VV 80 P. melanocarpa PR. 425 VV 81 P. ruficornis DEI-GISHym 19636 82 P. melanocarpa PR. 409 VV 83 P. armata PR. 465 VV 84 P. leucopus PR. 466 VV reared ex ovo from Tilia sp. 85 P. armata DEI-GISHym 80020 86 P. leucopus GBIF-GISHym 3246 (syntype of Nematus crassicornis Hartig).