Xyela koraiensis Blank & Shinohara, 2013

Blank, Stephan M., Shinohara, Akihiko & Altenhofer, Ewald, 2013, <strong> The Eurasian species of <em> Xyela </ em> (Hymenoptera, Xyelidae): taxonomy, host plants and distribution </ strong>, Zootaxa 3629 (1), pp. 1-106 : 23-25

Xyela koraiensis Blank & Shinohara , sp. nov.

Type locality: Russia, Primorskiy Kray, Ussuriysky Reserve .

Xyela kamtshatica: Rasnitsyn 1965: 492 , 514 (partly misidentified); Zhelochovtsev & Zinovjev 1995: 396 (partly misidentified)

Description. Female. Color. Head yellow with black pattern: two black stripes along frontal furrows ca 2 times wider than ocellar diameter, meeting black ocellar and postocellar area, black longitudinal medial spot of frons always present and separate from stripes along frontal furrows, kidney-shaped spots on vertex usually separate from black postocellar area ( Fig. 32 ). Antennae black, a little paler below. Thorax dorsally brown with more or less distinct paler pattern on pronotum, mesonotal lobes and mesoscutellum, tegulae pale, sometimes brown in middle, mesepisternum largely brown. Abdominal terga dark brown, lateral parts of terga 8 and 9+10 often pale brown, valvifer 2 basally pale and distally dark brown, membrane between valvifer 2 and valvula 3 white, valvula 3 black with small white ventral margin up to distal fifth ( Fig. 99 ). Legs pale brown, posterior coxae predominantly dark brown with small pale distal spot ventrally, femora sometimes with brown longitudinal stripes. Wing membrane clear, venation and pterostigma pale.

Morphology. Fore wing 3.7–4.2 mm long, 1.55–1.70 times longer than ovipositor sheath, Rs+M 100–240 µm long, 2r-m meeting Rs proximal to furcation of Rs1 and Rs2. Synantennomere 3 630–760 µm long, antennomere 4 150–200 µm long and 5.0–7.0 times longer than wide distally. Article 3 of maxillary palp 430–500 µm long, 1.45–1.65 times longer than scape and distinctly wider than synantennomere 3. OOL: POL = 1.70–1.90: 1. Ovipositor sheath 2.25–2,55 mm long, valvula 3 2.35–2.60 times longer than valvifer 2 and 9.0–10.5 times longer than wide ( Fig. 99 ). Valvula 3 of ovipositor sheath wedge-shaped, in distal third diamond-shaped in cross section, pale membranous area distally extending up to preapical region as small ventral pale margin of valvula 3, valvula 3 distally narrowing to round tip, sensilla field present and directed laterad, bearing ca 6 sensilla. Ovipositor indistinctly bent downwards. Valvula 1 of ovipositor compressed and slightly wedge-shaped, distal 0.07 narrowed to sclerotized tip bearing 4–5 serrulae and 7–8 annuli (6 of them perpendicular), ventral edge sloping up to tip, aulax terminating distally, olistether with 5 setae in distal half. Valvula 2 pale and evenly sclerotized, distal 0.07 tapering to sclerotized tip, in distal half with evenly spaced groups of sensilla campaniformia, dorsal margin of valvula 2 smooth with small prominences above sensilla groups. Posterior tibia 0.80–1.00 mm long, all claws with delicate subapical tooth.

Male. Color. Similar to female (see Fig. 31 for color pattern of head). Antennae usually pale brown. Hypopygium dark brown.

Morphology. Fore wing 3.4–3.8 mm long, Rs+M 60–175 µm long, 2r-m meeting Rs proximal to furcation of Rs1 and Rs2. Synantennomere 3 660–750 µm long, antennomere 4 200–220 µm long and 5.5–7.5 times longer than wide distally. Article 3 of maxillary palp 400–450 µm long, 1.35–1.65 times longer than scape. OOL: POL = 1.40–1.75: 1. Longitudinal apodeme of basiparamere curved, basal portion in lateral position, harpe about as long as wide in lateral view. Valviceps 1.50–1.65 times longer than wide on medial lobe, lateral lamella vertical with proximal and distal edge s-shaped, proximal lobe of penis valve 0.19–0.21 times as long as valviceps and 1.05–1.10 times as high as medial lobe, valviceps on medial lobe 1.40–1.45 times wider than on distal lobe, excision on lower edge 0.19–0.23 as deep as width of medial lobe, 2 distal flagella present, tip of longer flagellum reaching 0.70–0.80 width of distal lobe ( Fig. 131 ). Valviceps with median longitudinal sclerotization absent, medial lobe broad and slightly truncate on upper edge and evenly sloping down to distal edge, with dense group of 12–15(–25) cone-like sensilla along upper edge, upper edge between medial and distal lobe with dense pattern of setae. Posterior tibia 830–930 µm long, all claws with delicate subapical tooth.

Type material. Holotype ♂: “Ussuriyskij Res., Primorskii Kray, Russia, 21.– 26.5.1994, leg. A. Shinohara ”; [red:] “Holotypus ♂ Xyela koraiensis spec. nov. det. S. M. Blank 2001”. Genitalia kept inside small vial on pin of holotype. NSMT . Paratypes 12♀ 18♂, DEI, NSMT, ZMUM, ZIN .

Etymology. The species name, an adjective, is chosen in accordance with the strongly supposed host plant relationship.

Host plant. Ο Pinus koraiensis Sieb. & Zucc. ( Rasnitsyn 1965 under the name Xyela kamtshatica ).

Geographic distribution. Russia (Primorskiy Kray), South Korea ( Fig. 10 ).

Remarks. Xyela koraiensis and X. ussuriensis have pale wings, whereas other representatives of the alpigena group have infuscate wings. The former two taxa are separated from each other, among other characters, by the length of the ovipositor (shorter in X. koraiensis than in X. ussuriensis ) and the color of the hypopygium in males (brown in X. koraiensis and yellow in X. ussuriensis ). The association of the sexes is supported by the color of the distal abdominal segments and of the posterior coxae, which is generally darker in both sexes of X. koraiensis than in X. ussuriensis . The species identification of the males by means of the shape of the hypopygium as proposed by Rasnitsyn (1965) for X. kamtshatica auct. and X. ussuriensis is impossible, because in both species males with round, truncate or shallowly emarginate hypopygium occur. The relative size of medial and distal lobes of the valviceps overlaps between the species. Also the seta pattern of the penis valve is unusable due to the similarity in long series.

Under the name Xyela kamtshatica, Rasnitsyn (1965) associated females with a comparatively long ovipositor and males with a long, on the lower side shallowly excised valviceps, whereas he called females with a shorter ovipositor and males with a stout and more deeply excised valviceps X. ussuriensis . Actually the name kamtshatica refers to a species of the alpigena group, which is distributed in Kamchatka and subalpine Japan along with Pinus pumila (see X. kamtshatica ; Fig. 9 ).

According to Rasnitsyn (1965 and personal communication) Pinus koraiensis is the host plant of X. kamtshatica auct. Although rearing data are still lacking, this relationship is certainly correct. Combinations of two or three species of X. koraiensis , X. ussuriensis and X. rasnitsyni were observed on six collection sites in the Russian Far East and South Korea ( Figs 10 , 22 ). This coincidence certainly depends on a common larval host species. Only P. koraiensis occurs in all collection sites of these three Xyela species , and it is the only pine reported on collection labels.

Figures

FIGURE 9. Records of the East Asian Xyela species supposedly feeding on Pinus (Strobus) species: X. kamtshatica (21 specimens from 4 collection sites), X. pumilae (4 specimens from 2 collection sites) and X. sibiricae (8 specimens from 2 collection sites). Additional record of X. kamtshatica by Takeuchi (1938) included for Hokkaido. The rhomb-shaped symbol represents records of X. koraiensis, X. rasnitsyni and X. ussuriensis supposedly feeding on Pinus koraiensis (illustrated separately in Figs 10, 22). Legend for natural distribution of Pinus species: P. koraiensis (solid line, according to Mirov 1967), P. pumila (dotted line) and P.sibirica (dashed line, both combined from Sokolov et al. 1977 and Kremenetski et al. 1998).

FIGURE 10. Records of Xyela koraiensis (31 specimens from 5 collection sites) and X. ussuriensis (39 specimens from 10 collection sites), and natural distribution of the supposed host plant, Pinus koraiensis (solid line, according to Mirov 1967).

FIGURE 22. Records of Xyela rasnitsyni (27 specimens from 7 collection sites) and natural distribution of the supposed host plant, Pinus koraiensis (solid line, according to Mirov (1967).

FIGURES 24–41. Color pattern of head of Xyela species: X. longula group, X. lugdunensis group, X. alpigena group, X. meridionalis group. Legend: HT—holotype; LT—lectotype; PT—paratype. Legend for Fig. 25: kss—kidney-shaped spot; mfs—medial frontal spot; sff—stripe along frontal furrow.

FIGURES 95–104. Ovipositor sheaths of Xyela species. All figures at same scale. Legend: HT—holotype; PT—paratype.

FIGURES 126–135. Penis valves of Xyela species: X. longula groups, X. lugdunensis group, X. alpigena group, X. meridionalis group. 127, tentatively identified male of from Tence (France: Auvergne, MNHN), see text. 128, paratype of X. nigroabscondita.