Pristiphora pseudocoactula (Lindqvist, 1952)

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 : 34

Pristiphora pseudocoactula (Lindqvist, 1952) Figs 89-90, 204, 234, 236

Lygaeonematus pseudocoactulus Lindqvist, 1952: 115-116. Holotype ♀ not found in MZH. Type locality: Utsjoki, Lapland, Finland.

Lygaeonematus concolor Lindqvist, 1952: 117-118, syn. n. Holotype ♀ (DEI-GISHym31689) in MZH, examined. Type locality: Kilpisjärvi, Lapland, Finland.

Similar species.

The most similar species is P. alpestris , from which it can be distinguished by usually having darker coloration (black clypeus, labrum, metafemur, and valvula 3) and different lancet and penis valve (see the Key). The differences Lindqvist (1952) mentioned between concolor and pseudocoactula (coloration of labrum, pronotum, metafemur, and the amount of setae on the lancet) are small and not reliable, because the variation is continuous.

Genetic data.

Based on COI barcode sequences, P. pseudocoactula belongs to the same BIN cluster (BOLD:AAK9467) as P. alpestris (Fig. 5). Maximum distance within the BIN is 1.62% and minimum between species distance is 0.00%. The nearest neighbour to BOLD:AAK9467, diverging by minimum of 4.69%, is BOLD:ACO1401 ( P. euxantha ). Based on nuclear data, maximum within species divergence is 0.4% (based on four specimens and TPI) and the nearest neighbour is 0.7% different ( P. alpestris , only NaK).

Host plants.

Betula pubescens Ehrh. (ex ovo rearing experiments by VV). Possibly also B. nana L. (incomplete ex ovo rearing experiments by VV) and Salix sp. (reared ex larva by Lindqvist 1952, as P. concolor ).

Rearing notes.

Rearing no. 56/1970 as P. concolor : Saana, Finnish Lapland. On 5.VII.1970 several larvae were found on Betula pubescens var. pumila . Next year one female emerged and buds of B. pubescens were offered her. She laid several eggs in pockets on underside of young leaves, egg pockets were near veins rather close to leaf margin.

Ovipositing experiment no. 12/1972 as P. concolor : Finland, North Karelia, Kontiolahti, Venejoki. One captured female laid two eggs in pockets on undersides of young leaves of Betula nana , young larvae died for technical reasons (food too old).

Ovipositing experiment 15/1972 as P. pseudocoactula : Finland, North Karelia, Kontiolahti, Venejoki. On 2.VI.1972 one captured female laid one egg in pocket near the midvein on underside of young leaf of Betula pubescens . She laid no eggs on Betula nana or Salix aurita . Four larval instars were observed and prepupa was seen on 16.VI.1972. No extra moult after feeding.

Distribution and material examined.

West Palaearctic, Nearctic. Specimens studied are from Finland and Sweden.