Pristiphora borea (Konow, 1904)

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 : 36

Pristiphora borea (Konow, 1904) Fig. 212

Nematus astutus Cameron, 1885: 77-78. Nomen oblitum. Syntypes (♀♂) have not been found ( Lindqvist 1952). Type locality: not stated. Synonymised with P. borea by Liston et al. (2006).

Lygaeonematus boreus Konow, 1904: 196-197 (key). Nomen protectum. See Liston, Taeger and Blank (2006). Syntype ♂ (GBIF-GISHym3908) in SDEI, examined (severely damaged, abdomen missing). Type locality: Kanin Peninsula, Nenets Autonomous Okrug, Russia, and Vassijaure, Torne Lappmark, Sweden.

Pachynematus lapponicus Enslin, 1916: 462-463. 2 ♀ and 1 ♂ syntypes in ZSM, examined. Type locality: Lappland, Europe. Synonymised with Lygaeonematus boreus by Lindqvist (1952).

Similar species.

Species limits in the carinata group are still unclear.

Genetic data.

Based on COI barcode sequences, specimens of the carinata group are divided between four BIN clusters (BOLD:AAF4995, BOLD:ABU8603, BOLD:ACL1744, BOLD:ACL1745), which form a monophyletic group (Fig. 5). Minimal distances between these clusters are 1.2%-4.48%. Because of unresolved taxonomy, it is not yet clear how different species are divided among these BIN clusters. Based on nuclear data, maximum divergence within the group is 2.2% (based on ten specimens and TPI) and the nearest neighbour is 1.5% ( P. pseudocoactula , both genes combined) or 1.0% different ( P. wesmaeli , only NaK).

Host plants.

Betula nana L. ( Bland and Liston 1999, ex ovo rearing experiments by VV).

Rearing notes.

Ovipositing experiment no. 10/1970: Finland, North Karelia, Kontiolahti, Selkie. On 28-29.V. 1970 one captured female laid several eggs in pockets near leaf-margin on underside of the young leaves of Betula nana . Larvae hatched on 2.VI.1970 and 6 larval instars were observed; larvae eat margins of leaves. Last instar was some 30-40 days long. No “extra” moult after feeding, prepupae were seen on 27.VII.-12.VIII.1970.

Ovipositing experiment no. 15/1970: Finland, North Karelia, Tuupovaara. One captured female laid several eggs on leaves of Betula nana ; she did not lay any eggs on Vaccinium uliginosum . Larvae developed, as in earlier experiment.

Ovipositing experiments 17/1970 and 18/1970: Finland, North Karelia, Kontiolahti, Venejoki. Two females laid many eggs on Betula nana , but respectively no and only two eggs on Vaccinium uliginosum . Otherwise very similar results as in previous two experiments.

Ovipositing experiments no. 4/1988, 5/1988, 6/1988, and 7/1988: Finland, South Häme, Janakkala, Suurisuo. Four captured females laid eggs on 26-27.V.1988 in pockets on undersurface of leaves of Betula nana , four larval instars were observed in all rearings and last instar lasted long.

Larvae observed on Betula pubescens var. pumila (L.) Govaerts (= Betula pubescens ssp. czerepanovii) in Saana, Finnish Lapland on 27.VII.1971.

Distribution and material examined.

West Palaearctic, Nearctic. Specimens studied are from Finland and Russia (Nenets Autonomous Okrug).