Euura latiserra ( Malaise, 1921 )

Liston, Andrew, Vikberg, Veli, Mutanen, Marko, Nyman, Tommi & Prous, Marko, 2023, Palaearctic willow-catkin sawflies: a revision of the amentorum species group of Euura (Hymenoptera, Tenthredinidae), Zootaxa 5323 (3), pp. 349-395 : 373

Euura latiserra ( Malaise, 1921)

Figures 8 , 14D–E

Pontopristia latiserra Malaise, 1921: 14 . Described: syntypes, 5♀. Published type locality [as comment under P. romani , p. 14]: Vassijaure, Lappland [ Sweden, Torne Lappmark, Vassijaure]. Lectotype designated below.

Nematus (Pontopristia) latiserra: Zhelohovcev, 1988 .

Amauronematus (Pontopristia) latiserra: Liston, 1995 .

Euura latiserra: Sundukov 2017 .

Diagnosis. Female [male unknown]. Similar to dark specimens of E. amentorum , but differs in its distally narrower and less strongly widened valvulae 3; 1.0–1.5 × as wide as narrowest distal width of metatibia in E. latiserra versus 1.8–2.1 × as wide in E. amentorum . Average body size and the number of annular sutures of the lancet is greater than in E. amentorum .

Description. Female ( Fig. 8A ). Body length 3.2–5.4 mm. Black. Pale are only more or less mandibles, palps, labrum, tibiae, apices of femora. Cerci pale. Wing veins including fore wing pterostigma pale.

Head. In dorsal view moderately contracted behind eyes, and length posterior of eye about 0.50 × length of eye ( Fig. 8B ). Mostly dull with coriaceous sculpture except for labrum. Upper head densely setose; setae pale, about 0.8 × as long as anterior ocellus diameter. Clypeus slightly emarginate medially. Labrum apically rounded. Antenna 0.77–0.80 × as long as fore wing costa.

Thorax. Pronotum, mesoscutum and tegula densely punctate with small shiny interspaces; vestiture similar to upper head, adpressed. Lateral mesoscutal lobe approximately 1.33 × as long as greatest width. Mesoscutellum as broad as long, without longitudinal median furrow; finely sculptured and dull. Upper half of mesepisternum slightly sculptured ( Fig. 8C ), with small ventral glabrous patch; setae about 0.5 × as long as diameter of anterior ocellus.

Abdomen. Valvulae 3 in lateral view ( Fig. 8E ) clearly orientated upwards; tapering to the narrowly rounded tip. In dorsal view ( Fig. 8D ) subparallel-sided: widened slightly distally, then gently narrowing before the tip; 1.0–1.5 × as wide as narrowest distal width of metatibia. Cercus reaches past the tip of valvulae 3. Lancet ( Fig. 14D–E ): 17–19 annular sutures; lamnium long and low; moderately strongly curved (lower edge concave); serrulae distally somewhat lobed, basally more flat; basal annular sutures without ctenidial teeth; base of tangium with prominent, narrow lobe.

Male. Unknown.

Biology. Host plants: Salix lanata * (see records below).

Vikberg & E. O. Peltonen made the following observations: The larvae live among the ovaries, on which they mostly feed, but some feeding on the catkin stalks also occurred. Larva: head black, body with dark flecks, anal tergum black. Prepupa: head pale brown, body extensively grey. Three prepared larvae have the following measurements: head width 0.95, 0.96 and 0.98 mm, and body length (maximal extension) respectively 12.2, 12.6 and 12.7 mm.

Distribution. Northern Norway and Sweden.According to Sundukov (2017) widespread in the East Palaearctic from western Siberia to the Russian Far East.

Figures

FIGURE 8. Euura latiserra. A–E) ♀ lectotype NHRS-HEVA000003679. F) ♀ lance DEI-GISHym12678. Scale bar 1 mm.

FIGURE 14. Lancets.A–C Euura amentorum:A) PR.505VV, lobe projecting from base of tangium arrowed.B) Nematus suavis paralectotype DEI-GISHym12674. C) Pontopristia kamtchatica lectotype NHRS-HEVA000006355. D–E Euura latiserra: D) PR.486VV. E) Pontopristia latiserra lectotype NHRS-HEVA000003679.