Pristiphora luteipes Lindqvist, 1955

Pristiphora luteipes Lindqvist, 1955: 47-48. Holotype ♀ (DEI-GISHym20897) in MZH, examined. Type locality: Degerby, Uusimaa, Finland.

Similar species.

The most similar species is P. aphantoneura, from which it cannot be always distinguished morphologically. Vikberg (2006) mentions that the mesepisternum should show at least slightly coriaceous sculpture (fig. 19 and fig. 6a in Vikberg 2006), but should be completely smooth in P. aphantoneura (Fig. 18). However, the mesepisternum can also be completely smooth in P. luteipes, especially in southern European specimens. See Vikberg (2006) for additional minor characters for separating these species. Pristiphora beaumonti Zirngiebl, 1957 known from North Africa is possibly a synonym of Pristiphora luteipes Lindqvist. All the specimens of P. beaumonti studied from Morocco are extremely pale. Females have a completely yellow abdomen (Fig. 13) and even the thorax often has ventral and dorsal yellow markings. Males are darker: thorax and usually abdomen are black (one studied specimen had an almost completely yellow abdomen). However, all males from Morocco have a completely pale metafemur, unlike males from Portugal and Spain (with a mostly black metafemur), which we have identified as P. luteipes based on females that were collected at the same time from Salix . Females from Portugal, Spain, and Sardinia (Italy) are very similar to North European specimens of P. luteipes, but tend to have a completely smooth mesepisternum and dark brown pterostigma (slightly coriaceous mesepisternum and yellow pterostig ma in northern European specimens). However, the degree of coriaceous sculpture on the mesepisternum and the colour of pterostigma vary continuously and seem to correlate with latitude (specimens in the south tend to have a smoother mesepisternum and darker pterostigma). Lancets (Fig. 61) and penis valves (Fig. 101) of P. beaumonti are not distinguishable from P. luteipes (Figs 60, 103) or even from P. staudingeri (arctic or subarctic taxon; Figs 73-76, 97-100, 102). Males of P. luteipes were previously unknown (Vikberg 2006), but appear to be common in southern Europe (at least in Portugal and Spain). We have identified a possible male of P. luteipes (DEI-GISHym80049) also from Sweden, because according to its nuclear TPI sequence it seems to be closer to P. luteipes specimens than to P. staudingeri (Fig. 2), although COI barcode was identical to one of the P. staudingeri specimens (Fig. 1). The male from Sweden has distinctly coriaceous sculpture on the mesepisternum and a paler pterostigma compared to males from Spain and Portugal, which would fit the geographic pattern found in females. Because males of P. luteipes have a black metafemur and the penis valves are indistinguishable from those of P. staudingeri, identification of the Swedish male ( Härjedalen at an altitude of 840 m) remains uncertain. Distinguishing females of P. luteipes from P. staudingeri might not always work either, because we have studied two specimens ( P. staudingeri ?) from Sweden ( Jämtland County at an altitude 900 m) that were intermediate in morphology, having partly yellow metafemur (apically slightly yellow in the specimen W10115 and apically half yellow in W10105).

Genetic data.

Based on COI barcode sequences, P. luteipes belongs to the same BIN cluster (BOLD:AAG3568) as P. aphantoneura, P. bifida, P. confusa, P. opaca, P. pusilla, P. staudingeri, 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. luteipes compared to COI barcode sequences, mainly because of the uncertain identity ( P. luteipes or P. staudingeri, see above) of the specimen DEI-GISHym80049 (Fig. 2), which seems to be closer to two sequenced P. luteipes specimens than to other species.

Host plants.

Salix alba L., S. aurita L., S. babylonica L., S. repens L. S. rosmarinifolia L., S. phylicifolia L., S. viminalis L., S. purpurea L. (see Vikberg 2006); S. cinerea L. and S. fragilis L. (Loiselle 1909, as P. fulvipes).

Distribution and material examined.

Western Palaearctic. Specimens studied are from Finland, France, Germany, Great Britain, Italy, Norway, Portugal, Spain, and Sweden.