Pristiphora subopaca Lindqvist, 1955

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 : 36-38

Pristiphora subopaca Lindqvist, 1955

Pristiphora subopaca Lindqvist, 1955: 41-42. Holotype ♀ (http://id.luomus.fi/GL.5202) in MZH, examined. Type locality: Munksnäs, Uusimaa, Finland.

Pristiphora coniceps Lindqvist, 1955: 39-40, syn. n. Holotype ♀ (http://id.luomus.fi/GL.5207) in MZH, examined. Type locality: Pihtipudas, Central Finland, Finland. Note. The male paratype (http://id.luomus.fi/GL.5208) is not conspecific with the holotype female and belongs to P. melanocarpa ; therefore most records of P. coniceps in the literature based on the penis valve belong to that species.

Pristiphora brunniapex Lindqvist, 1960: 37-38, syn. n. Holotype ♀ in MZH, examined. Type locality: Pisa, Rovaniemi, Finland.

Similar species.

Based on the external morphology, the most similar species are P. albitibia , P. confusa , P. opaca , P. pusilla , and P. sootryeni . The species is best distinguished through the structure of male penis valve (Figs 91-92 ). Unfortunately, it is rather difficult to separate females from P. confusa and P. opaca as the differences in the lancets are small (Figs 62 - 69 ). Apical serrulae are perhaps less protruding and longer (Figs 66-69 ) than in P. confusa (Figs 62-63 ) and the basal part of the tangium lacks a fold that is present in P. opaca (Figs 64-65 ). Externally, the pterostigma is uniformly yellow (Fig. 27 ) unlike in P. confusa and P. opaca , in which the pterostigma is basally dark brown and apically brown (Fig. 28 ). In addition, the claws of P. subopaca tend to have a larger subapical tooth (Fig. 32 ) than in P. opaca (Fig. 31 ). Among the males, the most similar penis valves are of P. confusa and P. pusilla . The ventro-apical spine is bent more strongly and the pseudoceps is broader (Figs 91-92 ) than in P. confusa (Figs 89-90 ). Compared to P. pusilla (Figs 93-94 ), the ventro-apical spine is bent less strongly and the dorsal depression in the middle of pseudoceps is less distinct, which is clear only when compared to the left penis valve of P. pusilla (Fig. 93 ). The holotype of Pristiphora coniceps Lindqvist does not differ in any significant way from the holotype of Pristiphora subopaca Lindqvist. The characters mentioned in the structure of the head and thorax for Pristiphora coniceps in the original description ( Lindqvist 1955), that are supposed to differentiate this species from others in the Pristiphora ruficornis group, are minute and unreliable. The characters that help in species identifications in closely related species (colour of pterostigma and antennae, degree of coriaceous sculpture of mesepisternum, size of subapical tooth of claws, and the structure of the lancet) are not different between the holotypes of Pristiphora coniceps and Pristiphora subopaca . The host ( Salix ) mentioned for Pristiphora coniceps in the original description ( Lindqvist 1955) and by Kangas (1985) (as Salix caprea L.) also fits with the data recorded for P. subopaca ( Lindqvist 1965; Kangas 1985). Consequently we treat Pristiphora coniceps as a synonym of Pristiphora subopaca . We also treat Pristiphora brunniapex Lindqvist as a rare colour form (only the holotype and one additional female are known to us) of Pristiphora subopaca Lindqvist, because the only difference is that Pristiphora brunniapex has a pale tip of the abdomen (terga 7-10 or 8-10; Figs 10 , 12 ). Based on the second known specimen (DEI-GISHym20899, deposited in MZH) reared by J. Perkiömäki from Salix sp. (near Helsinki, Finland), we can say that the host is not different from Pristiphora subopaca either. Although the lancet of Pristiphora brunniapex cannot be distinguished from P. aphantoneura , P. luteipes and P. staudingeri , these species can be separated from Pristiphora subopaca - Pristiphora brunniapex by having different host ( Lathyrus pratensis for P. aphantoneura ), yellow metafemur ( P. aphantoneura and P. luteipes ), or as in P. staudingeri usually strongly coriaceous sculpture of mesepisternum and different habitat (arctic or subarctic).

Genetic data.

Based on COI barcode sequences, P. subopaca belongs to the same BIN cluster (BOLD:AAG3568) as P. aphantoneura , P. bifida , P. confusa , P. opaca , P. pusilla , and P. staudingeri (Fig. 1 ). The nearest neighbour (BOLD:AAQ2302, P. armata and P. leucopus ) is 2.76% different. Only one TPI sequence is available, which can be distinguished from other species (Fig. 2 ).

Host plants.

Salix caprea L. ( Lindqvist 1965; Kangas 1985) and S. phylicifolia L. ( Lindqvist 1965).

Distribution and material examined.

Western Palaearctic. Specimens studied are from Finland 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 87 - 96. Penis valves of Pristiphora ruficornis group. 87 P. bifida DEI-GISHym 80000 (arrow indicates a dorsal depression of the pseudoceps) 88 P. frigida NHRS-HEVA 000003861 (arrow indicates a membranous fold near the tip of the ventro-apical spine) 89 P. confusa DEI-GISHym 31265 90 P. confusa PR. 460 VV 91 P. subopaca DEI-GISHym 80030, left penis valve 92 P. subopaca paratype http: // id. luomus. fi / GL. 5203 93 P. pusilla DEI-GISHym 80029, left penis valve with strong dorsal depression of the pseudoceps (arrow) 94 P. pusilla DEI-GISHym 80029, right penis valve with weak dorsal depression of the pseudoceps 95 P. opaca PR. 459 VV 96 P. opaca http: // id. luomus. fi / GL. 5206, paratype of P. amaura Lindqvist.

Figures 62 - 65. Lancets of Pristiphora aphantoneura subgroup. 62 P. confusa holotype 63 P. confusa PR. 544 VV reared ex larva from Salix caprea 64 P. opaca DEI-GISHym 80032 (presence of a fold is indicated by an arrow) 65 P. opaca PR. 389 VV.

Figures 66 - 69. Lancets of Pristiphora subopaca. 66 PR. 403 VV 67 P. subopaca holotype 68 P. coniceps holotype 69 P. brunniapex holotype.

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 3 - 17. 3 Pristiphora bifida DEI-GISHym 31507, sawsheath with large scopa (arrows) in dorsal view 4 P. appendiculata DEI-GISHym 80025, sawsheath with large scopa (arrows) in apical view 5 P. albitibia DEI-GISHym 31514, head in dorsal view showing short postocellar area (lines and arrows) 6 P. geniculata DEI-GISHym 20961, head in dorsal view showing long postocellar area (lines and arrows) 7 P. appendiculata DEI-GISHym 31500, smooth mesopostnotum (arrow) 8 P. albitibia DEI-GISHym 31516, matt mesopostnotum (arrow) 9 P. ruficornis DEI-GISHym 31185, dorsal view 10 P. subopaca DEI-GISHym 20899, dorsal view 11 P. ruficornis DEI-GISHym 31185, lateral view 12 P. subopaca DEI-GISHym 20899, lateral view 13 P. beaumonti DEI-GISHym 20766, lateral view 14 P. melanocarpa DEI-GISHym 21031, abdomen in lateral view 15 P. luteipes DEI-GISHym 18872, abdomen in lateral view 16 P. armata DEI-GISHym 11092, tergum 8 in dorsal view with apical projection (arrow) 17 P. subopaca DEI-GISHym 31560, tergum 8 in dorsal view without apical projection.