ISSN 1911-2173

Revision of the World species of Xeris Costa (Hymenoptera: Siricidae)

Henri Goulet1, Caroline Boudreault1 and Nathen M. Schiff2

3. Xeris chiricahua Smith

Fig. C3.1 (female habitus)

Fig. C3.2 (male habitus)

Xeris chiricahua Smith, 2012: 251 ). Holotype female (USNM), labelled: [White] “RustlerPark ChiricahuaMts 13June56 ARIZ OLCartwright”; [White with red border] HOLOTYPE Xeris chiricahua Smith. Type locality: U.S.A., Arizona, Chiricahua Mountains, Rustler Park. Specimen in perfect condition. Schiff et al. 2012: 251.


Diagnostic combination

Among specimens with mainly clear wings and a white stripe on the lateral margin of the pronotum [chiricahua, caudatus, malaisei, melancholicus, pallicoxae, spectrum, and xylocola], X. chiricahua is recognized in both sexes by the long setae on the clypeus and frons, and by the dense pits on the gena ventral to the genal ridge.



Color. Head black except for large white spot on gena dorsal to middle of eye extending down to genal ridge and on gena between ridge and eye (Fig. B2.31); antenna black (apical 0.25 dark brown); last maxillary palpomere black. Thorax black except for white stripe extending from posterolateral to anterolateral angles, narrowing toward posterior angle (Fig. B2.36), and extending on vertical portion below anterior angle, the band 0.3 times as wide as lateral 0.5 of pronotum and not extending to lateral margin of pronotum. Legs light reddish brown but black on pro- and mesocoxae, black or mostly light reddish brown on metacoxa (Fig. C3.1). Fore wing clear except for a lightly tinted band in apical 0.25 and on posterior corner of cells 2CU and 3CU (Fig. C3.1); costal cell brown and most of area ventral to anal cells yellowish brown (as in Fig. B2.39); veins black (including veins C and R, and base of stigma on both sides of junction with vein 1r-rs) (as in Fig. B2.39). Abdomen black (Fig. C3.1). 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 1.0–1.5 times as long as diameter of a lateral ocellus (Fig. B2.33). Eye in lateral view (N=5) with its maximum height 1.3–1.6 times as long as its maximum length (Fig. B2.31), and maximum height of eye 0.34–0.48 times as long as maximum height of head (from transverse ridge on gena above mandible to top of head) (measurements as in Fig. B2.8). Gena in dorsal view with maximum distance between outer edges clearly wider than maximum distance between outer edges of eyes (Fig. C3.3) (in frontal view outer edges of eyes clearly not intersecting genae) (as in Fig. B2.5); in lateral view with distance between outer edge of eye and genal ridge 0.50–0.66 times as long as maximum length of eye (Fig. B2.31, measurements as in Fig. B2.77), with dense pits ventral to genal ridge and merged with pitted area of occiput (Fig. B2.31), and with quite dense and medium sized pits (diameter of pit about 0.2 times lateral ocellus diameter) between outer edge of eye and genal ridge (Fig. B2.31). Transverse ridge near mandible narrow, sharp and mainly smooth (as in Fig. B2.18). Vertex widely pitted and pits medium in size (diameter of pit 0.2–0.4 times lateral ocellus diameter) pits present from dorsoposterior edge of eye to occiput outside postocellar area, absent on about 0.5 of postocellar area (Fig. C3.3); pits quite dense and medium in size along all or most of sharply outlined median furrow, but a little more widespread near lateral ocelli (as  in Fig. C3.3).

Thorax. Pronotum in lateral view with coarse polygonal pits on almost all of surface (as in Fig. B2.97). Propleuron in lateral view with small polygonal pits in posterior 0.5 of disc and with medium polygonal pits in anterior 0.5 of disc (as in Fig. C12.7); in ventral view with dense medium teeth with smooth surface in between (as in Fig. B2.22). Transcutal furrow of mesonotum clearly outlined  and finely sculptured, thus mesoscutum and axilla clearly distinct (as in Fig. C2.3). Fore wing in middle 0.3 of vein 2A diverging very rarely slightly (Fig. C11.6) to usually considerably (as in Fig. C11.6) 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 absent, or reduced to a stump, but not extending toward posterior wing edge.

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 scale above furrow) (as in Fig. B2.93, insert); median basin with base (outlined by two lateral black longitudinal furrows) 0.8 times as wide as its median length, with maximum width of basin 1.3–1.6 times as wide as its median length and basin 0.6–0.8 times as long as medially median length of cornus (measurements as in Fig. A3.2). Cornus constricted in dorsal view, its minimum width (at constriction) 0.8 times as wide as maximum width of cornus subapically; with large teeth in apical 0.3 (as in Fig. B2.110). Sheath. Basal section 0.22–0.27 times as long as apical section (N = 4); lateral surface of apical section with well-defined ridge (as in Fig. B2.13, insert); total length 1.4–1.5 times as long as fore wing length. Ovipositor. Lancet with 26–30 annuli (first 15 annuli very hard to see, but still outlined (N = 2); junction of basal and apical sections of sheath aligned between 3rd–4th annuli; major pits present on 4–5 apical annuli before teeth annuli, and at most one preceding annuli with a very small pit (as in Fig. C1.18 without small pits).


Color. Head with large white spot on gena dorsal to middle of eye similar in size to female. Coxae, femora (except for light reddish brown at extreme apex), tibiae (except for sharp outlined yellowish-white spot at very base) (Fig. B2.38) and tarsi 1 and 2 or 1–3 (except for light reddish-brown extreme apex) black, and tarsomeres 3–5 or 4 and 5 light reddish brown (Fig. C3.2).

Thorax. Metatibia with deep notch on dorsal edge in basal 0.25 (Figs. B2.38 and C3.2).

Taxonomic notes

At first sight, specimens of X. chiricahua are similar to those of X. caudatus, X. malaisei, X. melancholicus, X. pallicoxae and X. spectrum because they share the white longitudinal band on the lateral margin of the pronotum. Adults of X. chiricahua are distinguished from the above species by the length of frontal and clypeal setae, the much denser pits on the vertex, and the dense pits on the gena below ridge merging with pits of the occiput.

Hosts and Phenology

The host of X. chiricahua is unknown, but females of Xeris with a long ovipositor and few pits on the ovipositor are known to attack Pinaceae. The Chiricahua Mountains are rich in pines at high elevations. The three specimens at the type locality were captured on June 13.


United States: Arizona, Colorado. Xeris chiricahua is recorded from two localities in Arizona and one in Colorado. The species probably occurs in Mexico (see map C41.3 in Schiff et al. 2012).

Specimens studied: 4 females and 1 male from CNC and USNM.