Pristiphora bifida ( Hellen , 1948)

Prous, Marko, Kramp, Katja & Liston 1, Veli VikbergAndrew, 2017, North-Western Palaearctic species of Pristiphora (Hymenoptera, Tenthredinidae), Journal of Hymenoptera Research 59, pp. 1-190 : 65

Pristiphora bifida ( Hellen, 1948) Figs 9, 25, 199, 267

Nematus (Pristiphora) bifidus Hellén, 1948b: 116-117. Lectotype ♀ (http://id.luomus.fi/GL.5214; designated by Prous et al. 2016) in MZH, examined. Type locality: Malla, Kilpisjärvi, Enontekiö, Finland.

Similar species.

Externally, perhaps the most similar species is P. frigida , from which it can be distinguished by having pale hind trochanters, trochantelli, and tibiae (black or brown in P. frigida ). In addition, antennae of males have numerous and clearly visible stout black setae among finer paler ones (Fig. 18), while in P. frigida only a few black setae are barely visible (Fig. 17). The lancets (Figs 199-200) and penis valves (Figs 267, 274) are also different. The apical serrulae are somewhat shorter and more protruding, and the tangium of the lancet tends to be longer and narrower (Fig. 199) than in P. frigida (Fig. 200). The penis valve lacks (Fig. 267) a membranous fold near the tip of the valvispina (present in P. frigida ; Fig. 274) and the pseudoceps has a distinct dorsal depression in the middle or basal part (absent in P. frigida ).

Genetic data.

Based on COI barcode sequences, P. bifida belongs to the same BIN cluster (BOLD:AAG3568) as P. aphantoneura , P. confusa , P. luteipes , P. opaca , P. pusilla , P. staudingeri , and P. subopaca (Fig. 4). Maximum distance within the BIN is 3.33% and minimum between species distance is 0.00%. The nearest neighbour to BOLD:AAG3568, diverging by minimum of 2.76%, is BOLD:AAQ2302 ( P. armata and P. leucopus ). Based on nuclear data, maximum within species divergence is 0.1% (based on two specimens and both genes combined) and the nearest neighbour is 0.0% different ( P. confusa , P. luteipes , or P. beaumonti , only TPI). When including TPI introns, the nearest neighbour is still 0.0% different ( P. confusa or P. luteipes ).

Host plants.

Salix viminalis L. ( Liston and Burger 2009). In Kilpisjärvi (Finland) some other species must be the host, as S. viminalis does not occur there.

Distribution and material examined.

West Palaearctic. Specimens studied are from Finland, Germany, Norway, and Sweden.