Pristiphora staudingeri (Ruthe, 1859)

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 : 34-36

Pristiphora staudingeri (Ruthe, 1859)

Nematus Staudingeri [sic!] Ruthe, 1859: 306-307. Lectotype ♀ (designated by Vikberg 1978) in NMW, examined. Type locality: Iceland.

Pristiphora circularis Kincaid, 1900: 350. Holotype ♀ (USNMENT00778165) in USNM, not examined. Type locality: Popof Island, Alaska, USA.

Pristiphora hyperborea Malaise, 1921: 11. Lectotype ♀ (NHRS-HEVA000003650; designated by Vikberg 1978) in NHRS, examined. Type locality: Torne Träsk, Torne Lappmark, Sweden.

Pristiphora asperlatus Benson, 1935: 35-38. Holotype ♀ in BMNH, not examined. Type locality: Mount Braeriach, Inverness, Scotland, United Kingdom.

Similar species.

Based on the external morphology, the most similar species are P. astragali , P. confusa , P. luteipes , P. opaca , P. pusilla , P. sootryeni , and P. subopaca . The combination of usually strongly coriaceous sculpture on the mesepisternum (Fig. 20 ), the habitat (arctic or subarctic), and the structure of the lancet (absence of small spiny pectines or dentes semicirculares and well developed ctenidia; Figs 73-76 ) or penis valves (Figs 97-100 , 102 ) should usually enable distinction of the species from other similar species. Vikberg (1978) treated P. hyperborea Malaise tentatively as a separate species, but no characters distinguish it unambiguously from P. staudingeri . The small differences in lancets (Figs 73-76 ), penis valves (Figs 97-100 , 102 ) and the sculpture of the mesepisternum most likely represent within species variation and therefore we treat P. hyperborea as a synonym of P. staudingeri as suggested by Lindqvist (1953). In addition, penis valves and lancets cannot be distinguished from P. luteipes and P. beaumonti (see under P. luteipes ) (Figs 60-61 , 101 , 103 ), which can have a completely smooth mesepisternum (Fig. 19 ) and can be extremely pale (Fig. 13 ). Because of the black metafemur, females of P. staudingeri can easily be distinguished from P. luteipes (completely yellow metafemur; Fig. 23 ), but two studied Swedish specimens ( Jämtland County at an altitude 900 m) had an apically slightly yellow (W10115) or even apically half yellow metafemur (W10105), weakening the distinction between these taxa.

Genetic data.

Based on COI barcode sequences, belongs to the same BIN cluster (BOLD:AAG3568) as P. aphantoneura , P. bifida , P. confusa , P. opaca , P. pusilla , and P. subopaca (Fig. 1 ). The nearest neighbour (BOLD:AAQ2302, P. armata and P. leucopus ) is 2.76% different. It is not clear if nuclear TPI sequences allow better identification of P. staudingeri compared to COI barcode sequences, mainly because the identity of the male specimen DEI-GISHym80049 (Fig. 2 ) is uncertain. According to TPI sequence, this male from Sweden is closer to P. luteipes (males of which are not known from northern Europe for certain) than to P. staudingeri (Fig. 2 ), but morphological characters and collecting locality ( Härjedalen at an altitude of 840 m) does not allow for certain identification. In addition, COI barcode of DEI-GISHym80049 is identical to one of the P. staudingeri specimens (Fig. 1 ).

Host plants.

Salix herbacea L. and S. phylicifolia L. ( Vikberg 1978).

Distribution and material examined.

Western Palaearctic, Nearctic. Specimens studied are from Finland, France, Great Britain, Iceland, Norway, Sweden, and Switzerland. The species should be removed from the fauna of Denmark. Publications (e.g. Taeger et al. 2006) mentioning this species from Denmark are based on misinterpretation of Nielsen and Henriksen (1915), who actually recorded P. albitibia under the name P. staudingeri , as evidenced by the mentioned hostplant, Vicia cracca .

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 73 - 76. Lancets of Pristiphora staudingeri showing variation in the number of ctenidia. 73 PR. 441 VV with ctenidia on annulets (3) 4 - 12 (13) 74 PR. 402 VV with ctenidia on annulets 3 - 13 75 PR. 373 VV with ctenidia on annulets 3 - 14 76 PR. 457 VV with ctenidia on annulets (2) 3 - 15.

Figures 97 - 104. Penis valves of Pristiphora ruficornis group and P. rufipes. 97 P. staudingeri PR. 361 VV 98 P. staudingeri PR. 447 VV 99 P. staudingeri PR. 352 VV 100 P. staudingeri PR. 453 VV 101 P. beaumonti DEI-GISHym 21176 102 P. staudingeri DEI-GISHym 21228 103 P. luteipes DEI-GISHym 19681 104 P. rufipes DEI-GISHym 15263.

Figures 58 - 61. Lancets of Pristiphora aphantoneura subgroup. 58 P. aphantoneura holotype 59 P. aphantoneura PR. 695 VV reared from Lathyrus pratensis 60 P. luteipes PR. 696 VV reared from Salix phylicifolia 61 P. beaumonti DEI-GISHym 20927.

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.