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Revision of the World species of Xeris Costa (Hymenoptera: Siricidae)
CJAI 28 -- September 25, 2015
doi: 10.3752/cjai.2015.28
http://zoobank.org/References/1360ED3A-8330-43BD-B051-2DDBBBD76AA0
Henri Goulet1, Caroline Boudreault1 and Nathen M. Schiff2

6. Xeris himalayensis Bradley

Fig. C6.1 (female habitus)

Fig. C6.2 (male, lateral habitus)

Fig. C6.3 (male, dorsal habitus)

Xeris himalayensis Bradley, 1934: 145. Holotype female (USNM), examined by HG, labelled: [White] “Deoban 9000 ft Chakrata, Div., 17.18.vi.23 CFC Beeson”; [White] “39”; [Red] “ HOLOTYPE Xeris himalayensis ♀  J. C. Bradley”; [White barcode] USNM ENT 00778280”. Type locality: “India, Uttaranchal, Deoban Chakrata, 3000 m”. Type in perfect condition. Hedicke, 1938: 23 (catalog); Benson, 1941: 397; Benson, 1943: 30, 31, 32, 47; Benson, 1951: 22; Viedma & Suárez, 1961: 20, 22, 23; Ashraf, 1964: 66 (hosts); Dharmadhikari & Achan, 1965: 77–78 (hosts); Vasu & Saini, 1999: 275 (species status re-instated); Wei et al., 2006: 556; Saini et al., 2006: 599; Saini, 2009: 81, 82; Taeger et al., 2010: 105.

Xeris spectrum himalayensis; Maa, 1949: 82, 88, 170 (change in status). Cameron, 1965: 15–16; Smith, 1978: 84 (catalog); Xiao & Wu, 1982: 350 Fig. 2; Xiao & Wu, 1983: 6, plate IV Fig. 4; Xiao et al., 1992: 42; Xiao, 2006: 200.

Neoxeris melanocephala Saini & Singh, 1987: 177. Holotype female (INPC), not examined. Only one paratype (PUPC) studied, labelled:  “Himachal Pradesh, Dalhousie, Kalatop”, “2400 m, 13.7.1984, Saini and Singh". Type locality: “India, Himachal Pradesh, Dalhousie, Kalatop”. Abe & Smith, 1991: 56; Saini et al., 2006: 598; Taeger et al., 2010: 105. NEW SYNONYM.

Xeris indianus Vasu & Saini 1999: 277. Holotype female (INPC), not examined, labelled: “Uttar Pradesh, Konain (Chakrata), 2600 m, 25.5.1996, coll. M. S. Saini”. Type locality: India, Uttar Pradesh, Konain (Chakrata). Saini et al., 2006: 599 (list); Saini, 2009: 81, 82, 83 (catalog); Taeger et al., 2010: 105 (catalog). NEW SYNONYM.


Diagnostic combination

Among specimens with a black abdomen, dense pits between dorsal edge of eye and occiput outside postocellar area [himalayensis, chiricahua, indecius, and cobosi], in females without a marginal lateral stripe on the pronotum (pronotum black, at most with an anterior white spot not extending to posterolateral angle) [cobosi and indecisus], X. himalayensis is recognized in both sexes by the frontal setae that are 0.7–1.2 times as long as the diameter of lateral ocellus and the clear fore wings, and in females by the black flagellum and coxae.

Description

FEMALE

Color. Head black or black with white spot on gena dorsal to middle of eye; white spot varying in size from absent to expanded over dorsal 0.5 of gena (Fig. C6.6–6.8); antenna black; last maxillary palpomere black (Fig. C6.6). Thorax black or pronotum with white spot in anterior 0.5 of lateral margin (Figs. B2.54 and Figs. B2.55). Legs beyond coxae light reddish brown, coxae black (Figs. B2.48). Fore wing clear except for lightly tinted band in apical 0.25, and on posterior corner of cells 2CU and 3CU (as in Figs. B2.66); costal cell dark yellowish brown (paler in old specimens) (as in Figs. B2.39); most of area ventral to anal cells yellowish brown; veins C, R, and base of stigma on both sides of junction with vein 1r-rs black (as in Figs. B2.39). Abdomen black (Fig. C6.1). Sheath with apical section black and basal section reddish brown.

Head. Distance between nearest eye edge and lateral ocellus edge about 1.1–1.5 times as long as distance between inner edges of lateral ocelli (as in Fig. C1.5). Setae on clypeus 0.7–1.2 as long as the diameter of a lateral ocellus (Fig. C6.5). Eye in lateral view (N = 22) with its maximum height 1.22–1.56 times as long as its maximum length (Fig. B2.18), and maximum height of eye 0.43–0.53 times as long as maximum height of head (from transverse ridge on gena above mandible to top of head, measurements as in Figs. B2.8). Gena in dorsal view with maximum distance between outer edges clearly wider than maximum distance between outer edges of eyes (Figs. C6.5) (in frontal view outer edges of eyes clearly not intersecting genae) (as in Figs. B2.5), and in lateral view with distance between outer edge of eye and genal ridge 0.37–0.56 times as long as maximum length of eye (Fig. B2.18, measurements as in Fig. B2.77),  with few pits ventral to genal ridge, and with many medium to large size pits (diameter of pits 0.2–0.5 times lateral ocellus diameter) between outer edge of eye and genal ridge (mainly near eye) (Fig. B2.32). Transverse ridge above mandible narrow, sharp and mainly smooth (Fig. B2.18). Vertex densely pitted and pits large (diameter of pit 0.4–0.6 times lateral ocellus diameter), pits present from dorsoposterior edge of eye to occiput outside postocellar area, absent on most of postocellar area (Figs. C6.5); pits scattered and large in size along all of shallowly outlined and gutter-like median furrow but more widespread near lateral ocelli (Figs. C6.5).

Thorax. Pronotum in lateral view with coarse polygonal pits on 0.7–1.0 of posterior surface (as in Fig. B2.97). Propleuron in lateral view mainly with medium size polygonal pits (as in Fig. C12.7); in ventral view generally with dense small teeth with smooth surface in between (as in Fig. B2.11). Metanotum with surface posterior to cenchrus and lateral 0.5 of metascutellum finely pitted (pit 0.1 times as wide as diameter of lateral ocellus) (Fig. C6.4). Fore wing in middle 0.3 of vein 2A diverging very rarely slightly (as in Fig. C11.6) to usually considerably (as in Fig. C12.6) away from wing edge, and then more (as in Fig. C11.6) or less (as in Fig. C12.6) abruptly curved away from wing edge; vein 3A mainly absent, occasionally reduced to a stump, rarely extending slightly as a short nebulous vein, and rarely extending along posterior margin of wing (N = 10).

Abdomen. Tergum 9 with meshes of microsculpture on ventral half below and above longitudinal furrow near center not well impressed and sculpticells clearly flat (slightly raised as scales above furrow) (as in Fig. B2.93, insert); median basin with base (outlined by two lateral black longitudinal furrows; N = 1) about 0.7 times as wide as its median length, with maximum width of basin about 1.3 times as wide as its median length and basin about 0.5 times as long medially as median length of cornus (measurements as in Fig. A3.2). Cornus constricted in dorsal view, its minimum width (at constriction) about 0.8 times as wide as maximum width subapically (as in Fig. C1.15); with large teeth in apical 0.3 (as in Fig. B2.110). Sheath. Basal section 0.23–0.37 times as long as apical section (N = 28) (Fig. C6.1); lateral surface of apical section with well-defined ridge (as in Fig. B2.13, insert); total length 1.2–1.4 times as long as fore wing length. Ovipositor. Lancet with 28–32 annuli (first 15 annuli hard to see, but still outlined; N = 7); junction of basal and apical sections of sheath aligned with 3rd or between 3rd–4th annuli; major pits present on last 4–5 apical annuli before teeth annuli, and with 11–19 annuli with a very small pit on each of the preceding annuli, starting anywhere between 3rd–10th annuli (as in Fig. C1.18).

MALE

Color. Head with dorsal spot behind eye very large, extending from vertex to surface between eye and genal ridge (Fig. 6.8). Pronotum with lateral spot often extending posteriorly as a band but not reaching posterolateral angle and much narrower posteriorly (Fig. C6.3). Coxae and trochanters black; femora reddish brown to black; tibiae black with sharply outlined white spot in basal 0.2; tarsomeres 1 and 2 or 1–3 black, tarsomeres 3–5 or 4 and 5 light reddish brown. (Fig. C6.2).

Thorax. Metatibia with shallow notch on dorsal edge in basal 0.25 (as in Fig. C6.2).

Taxonomic notes

The synonymy of this species was difficult to assess. We saw a paratype of Neoxeris melanocephala. This specimen perfectly matches specimens of X. himalayensis. Moreover, there is great variation in the expression of the genal spot in females studied: no spot or barely suggested 42%, small 26%, typical (e.g., X. pallicoxae) 16%, and as large as in males 16%. Therefore, the probability of finding specimens without a genal spot is very high. Our interpretation of X. indianus is based on the paper and keys to species of Xeris of India by Vasu and Saini (1999). The status of X. indianus is unclear as we have only a description. Dr. Saini tried hard to send us specimens, but they were damaged before leaving India and never arrived.

The first road block is the first couplet leading to X. himalayensis (key by Vasu et al. 1999). The tegula (it is the humeral plate), and the apical 0.5 of the cornus is described as yellow. The median fovea is in the form of a deep and transverse groove below the median ocellus. The frons is at the level of eyes. No such specimen (including the holotype) of X. himalayensis seen by us matches the above features. We do not know what species the single examined specimen from China is. In the above couplet it is not clear what the authors are referring to when mentioning a rugose and large triangular mesoscutellar appendage (to us they are probably describing the mesoscutellum not the appendage, and the mesoscutellum seems to be the mesoscutum!). In all species of Xeris studied the appendage is smooth and narrow (with not enough surfaces for pits). The second couplet separates X. indianus from X. spectrum. Wing color cannot be used here as it is variable and affected by the age of the pinned specimen. The median length of the pronotum varies between 3–5 times as long as the length of the median ocellus in our specimens. All characters fall within the range of variation of specimens we studied even from a single site. The X. indianus description of the females and males (with its very large genal spot) matches our specimens of X. himalayensis, including the holotype. Both have sympatric ranges. Moreover, their concept of X. spectrum falls within the normal variation of X. himalayensis. Xeris spectrum is a transpalaearctic species in boreal regions, nowhere near the Himalayan Mountains. Based on the above interpreted character states, we consider X. indianus as a junior synonym of X. himalayensis.

Geographical variation

We did not recognize any pattern of geographical variation from our limited sample. It seems that females without a genal spots are more commonly seen in Pakistan than elsewhere, and males may have a reddish-brown or black metafemur.

Hosts and phenology

Xeris himalayensis has a wide host range within Pinaceae (Ashraf 1964). The hosts are:  Abies pindrow, Cedrus deodara, Picea smithiana,and Pinus roxburghii.

Based on 28 field-collected specimens, the earliest and latest capture dates (they may be emergence dates) are late February to mid-July.

Range

India: Kashmir, Punjab, Himachal Pradesh, Uttar Pradesh. Nepal: locality. Pakistan: locality. Xeris himalayensis is recorded along the Himalayan Mountain range from Pakistan to Nepal between 1700 and 3000 meters.

Specimens studied: 25 females and 18 males from PUPC, CNC, FRNZ, SDEI, and USNM.

Specimens for molecular studies: 1 specimen. See Fig. D1.1. For the specimen the following is recorded: country, year, state/province, specimen code (in italics), and number of base pairs.

NEPAL: Simikot: 2014, DEIGISHym19732, 658.

Table of contents Abstract Introduction Materials and Methods Biology Hosts Parasitoids Morphology Key DNA References Citation Appendices PDFs