Pristiphora pusilla Malaise, 1921

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 : 72

Pristiphora pusilla Malaise, 1921 Figs 18, 32, 201, 271

Pristiphora pusilla Malaise, 1921: 11-12. Lectotype ♂ (NHRS-HEVA000004942; designated by Prous et al. 2016) in NHRS, examined. Type locality: Torne Träsk, Torne Lappmark, Sweden.

Pristiphora amaura Lindqvist, 1955b: 43-45. Holotype ♀ (http://id.luomus.fi/GL.5205) in MZH, examined. Type locality: Kangasala, South Häme, Finland.

Similar species.

Based on the external morphology, the most similar species are P. albitibia , P. astragali , P. confusa , P. opaca , P. sootryeni , P. staudingeri , and P. subopaca . The species is best distinguished through the structure of male penis valve (Figs 271) and female lancet (Fig. 201). In females, the lack of small spiny pectines (or dentes semicirculares) on the inner surface of the lancet, and weakly developed setae, distinguish it from other similar species. Male penis valves are asymmetric, the left one (Fig. 271) having a noticeably stronger dorsal depression in the middle of pseudoceps and a more strongly bent valvispina than the right one (Fig. 94 in Prous et al. 2016). The most similar penis valves are those of P. subopaca (Fig. 269), which have a less distinct dorsal depression in the middle of pseudoceps and a less strongly bent valvispina, but this difference is clear only when compared to the left penis valve of P. pusilla . Externally, P. pusilla can usually be distinguished from P. subopaca by having ventrally paler antennae (uniformly black in P. subopaca ; Fig. 15), which is more evident in males (Fig. 18).

Genetic data.

Based on COI barcode sequences, P. pusilla belongs to the same BIN cluster (BOLD:AAG3568) as P. aphantoneura , P. bifida , P. confusa , P. opaca , 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 a minimum of 2.76%, is BOLD:AAQ2302 ( P. armata and P. leucopus ). Based on nuclear data, maximum within species divergence is 0.2% (based on seven specimens and TPI or both genes combined) and the nearest neighbour is 0.1% different ( P. confusa or P. subopaca , only TPI).

Host plants.

Unknown.

Distribution and material examined.

Western Palaearctic. Specimens studied are from Finland, Norway, and Sweden.