ISSN 1911-2173
Revision of the World species of Xeris Costa (Hymenoptera: Siricidae)


CJAI 28 — September 25, 2015

doi: 10.3752/cjai.2015.28


Henri Goulet1, Caroline Boudreault1 and Nathen M. Schiff2




8. Xeris malaisei Maa, new status


Fig. C8.1 (female habitus)


Fig. C8.2 (male habitus)


Xeris spectrum malaisei Maa, 1949: 88. Syntype females (TARI), examined by Henri Goulet. Though, Maa (1949) did not mention specifically a specimen as holotype, one of the two specimens from the same locality has a label identifying it as a holotype. The segregated specimen is labelled: [White] “TAIWAN TAIHEIZAN 9.v.1942 A. MUTUURA”; [White with black frame] “Xeris spectrum malaisei subsp. n. Holotype ♀ det. T. MAA 1949”; [red circle] “TARI”. Type locality, Taiwan, Taiheizan. Maa, 1950: 21; Cameron, 1965: 16; Chou & Naito, 1991: 91; Xiao et al., 1992: 42; Xiao, 2006: 200; Wei, et al,. 2006: 557; Schiff et al. 2012: 248..



Diagnostic combination


Among specimens with a light yellow cell C in the fore wing, with a white base of stigma on both sides of junction with vein 1r-rs, and with short setae (0.6–0.7 times as long as diameter of lateral ocellus) on the clypeus [malaisei, pallicoxae, spectrum, xanthoceros and xylocola], X. malaisei is recognized in both sexes by the wide smooth median area dorsally on the pronotum, in females by the reddish-brown color in apical 0.3 of antenna, and in males by the the dark brown or black metatarsomere 5.






Color. Head black except for white spot on gena dorsal to middle of eye; white spot basically oval, extending to genal ridge (Figs. B2.8 and as in B2.139); antenna black and reddish brown in apical 0.25–0.3 (B2.115); last maxillary palpomere black (Fig. B2.8). Thorax black except for white longitudinal band extending from posterolateral to anterolateral angles of pronotum including vertical portion of anterolateral angle, the band 0.4–0.7 times as wide as lateral 0.5 of pronotum and usually (at low elevation) extending to lateral margin of pronotum (as in B2.134). Coxae black and legs beyond coxae light reddish brown (Fig. C8.1) except in Taiwan where coxae, trochanters, diffused area in middle of metafemur, apical 0.5 of tarsomeres 1 and tarsomeres 2–5 brown (Fig. B2.108). Fore wing clear except for lightly tinted band in apical 0.25, and on posterior corner of cells 2CU and 3CU (Fig. B2.67); costal cell very light yellow (possibly bleached in old specimens) (as in Fig. B2.40); most of area ventral to anal cells yellowish brown; veins black (including veins C and R, but base of stigma on both sides of junction with vein 1r-rs white) (as in Fig. B2.40). Abdomen black (Fig. C8.1). 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 0.6–0.7 as long as diameter of a lateral ocellus (Fig. B2.8). Eye in lateral view (N = 20) with its maximum height 1.2–1.6 times as long as its maximum length (Fig. B2.8), and maximum height of eye 0.44–0.53 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 (as in Fig. B2.41) (in frontal view outer edges of eyes clearly not intersecting genae) (as in Figs. B2.5), in lateral view with distance between outer edge of eye and genal ridge 0.32–0.54 times as long as maximum length of eye (Fig. B2.8, measurements as in Fig. B2.77), and with very small to moderate size pits (diameter of pit 0.05–0.2 times lateral ocellus diameter) between outer edge of eye and genal ridge (mainly near eye) (Figs. B2.8 and B2.131). Transverse ridge above mandible narrow, sharp and mainly smooth (as in Fig. B2.18), with few or no pits ventral to genal ridge. Vertex scarcely pitted and pits medium in size (diameter of pit 0.2–0.25 times lateral ocellus diameter), pits present from dorsoposterior edge of eye to occiput outside postocellar area, absent on most of postocellar area (as in Fig. B2.43); pits scattered and medium in size along all of shallowly outlined and gutter-like median furrow but a little more widespread near lateral ocelli (as in Fig. B2.43).

Thorax. Pronotum in lateral view with coarse polygonal pits on 0.3–0.7 of posterior surface (as in Fig. B2.97). Propleuron in lateral view basically with medium polygonal pits (as in Fig. C12.7); in ventral view generally with dense small teeth often in front of impressed pit with smooth surface in between (as in Fig. B2.22). Fore wing in middle 0.3 of vein 2A diverging very slightly away from wing edge (Fig. C8.3), and then more abruptly curved away from wing edge (Fig. C8.3); vein 3A absent (91%) or reduced to a stump (9%), not extending slightly as a short nebulous vein, and not extending along posterior margin of wing (N = 33).

Abdomen. Tergum 9 with meshes of microsculpture on ventral half above longitudinal furrow near center well impressed and sculpticells clearly scale-like (as in Fig. B2.92, insert); median basin with base (outlined by two lateral black longitudinal furrows; N = 6) 0.7–1.1 times as wide as its median length, with maximum width of basin 1.4–1.76 times as wide as its median length, and basin 0.43–0.47 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 0.26–0.46 times as long as apical section (N = 32) (Fig. C8.1); lateral surface of apical section with well-defined ridge (as in Fig. B2.13, insert); length 1.2–1.4 times as long as fore wing length. Ovipositor. Lancet with 27–33 annuli (first 15 annuli hard to see, but still outlined; N = 15); junction of basal and apical sections of sheath aligned between 3rd–4th or 4th–5th annuli; major pits present on last 4–5 apical annuli before teeth annuli, and 8–20 preceding annuli with a with very small pit, on each the preceding annuli 2–14 (as in Fig. C1.18).





Color. Head with dorsal spot behind eye usually larger in size than in many females and extending between eye and genal ridge (Fig. B2.131). Pronotum with lateral longitudinal band narrower than in females (0.3 times as wide as pronotal half), the band becoming narrower posteriorly and not extending to lateral edge of pronotum (Fig. C8.2). Coxae black; trochanter generally black; pro- and mesofemur reddish brown to black, metafemur black; tibiae light reddish brown in basal 0.3 and sharply separated from black surfaces, protibia light reddish brown with a narrow to wide longitudinal band in apical 0.5 along outer 0.2–0.5 of dorsal surface and often with very narrow longitudinal inner band on dorsal surface with black in apical 0.5, mesotibia light reddish brown with black transverse band in apical 0.6, and metatibia black except for sharply outlined yellowish-white spot at base (Fig. C8.2 and for hind leg Fig. B2.123); pro- and mesotarsomeres 1 light reddish brown in basal 0.1–0.8 and black thereafter; tarsomeres 2, 3, 4 and 5 dark brown to black, metatarsomere 1 black (except reddish-brown base and extreme apex) (Figs. B2.119, B2.121 and C8.2).

Thorax. Fore wing in apical 0.3 of vein 2A not subparallel with wing edge and less abruptly curved away from wing edge and broadly curved in central section (as in Figs. C11.6). Metatibia with shallow notch on dorsal edge in basal 0.25 (Figs. B2.119).

Taxonomic notes


Until we studied the holotype and paratype females of X. malaisei, we did not associate them with the northern specimens from northern China, Korea, Japan and Russia. Maa (1949) stressed the color pattern of the femora. Maa (1950) reported a third female matching the first two. In Taiwan, the color pattern of the femora, trochanters, tarsi, and the marginal longitudinal band of the pronotum is darker than farther north in eastern Asia. The Taiwanese specimens are found at high elevation with a markedly increased precipitation which probably selects for dark specimens (Goulet 1986, see Geographical Variation under Dolerus yukonensis Norton). In Hokkaido, the northern major Japanese island, specimens at high elevation also have darker color patterns especially on the pronotum. For these reasons we do not put too much weight on color patterns.


Other structures were considered as more significant in studying both populations. The Taiwanese females share with those farther north the fore wing anal vein shape, the length of the apical section of the sheath relative to the basal section, the number of annuli with a small pits anterior to the apical annuli with large pits, the flagellum color pattern, and the sculpture of the lateral surface of the pronotum and of the propleuron. Therefore, we consider the populations of northern China, Korea, Japan, and adjacent Russia as conspecific with the Taiwanese population. We do not recognize them as subspecies.


Xeris malaisei females are distinguished from X. caudatus, X. melancholicus and X. pallicoxae by coxal and flagellum color, from X. caudatus and X. melancholicus by color at base of stigma at junction with vein 1r-rs and costal cell. Xeris malaisei females are distinguished from X. pallicoxae by a very small pit on many annuli preceding the typical apical annuli, by the macrosculpture on the longitudinal band and lateral surface of the pronotum and on the lateral surface of the propleuron, and in males by femur color. Xeris malaisei is also distinguished from X. spectrum by genal spot shape, in females by shape of fore wing vein 2A, and in males by the tarsi color pattern. X. malaisei is also quite similar to X. xanthoceros and X. xylocola. Females of both species have a flagellum that is more extensively light reddish brown than in X. malaisei. Both sexes of X. malaisei differ from these species by the shape of fore wing vein 2A.


Geographical variation


As noted under “Taxonomic Notes”, the females of Xeris malaisei from Taiwan are more darkly colored (e.g., black metafemur) than in the northern portion of the range. In the north at low elevations, the longitudinal marginal band may be very large (each band may be 0.5–0.7 as wide as the dorsal half of the pronotum) and in males tarsomere 1 is mainly pale in basal 0.3–0.8. However, in the mountains of Hokkaido, some specimens have narrow longitudinal bands on the pronotum that may not extend to the posterolateral angle (each band may be 0.2–0.4 as wide as the dorsal half of the pronotum) and in males tarsomere 1 is mostly black. It seems that the cooler the environment due to altitude and/or latitude the darker the specimens.


Hosts and phenology


Xeris malaisei probably has a wide host range. The reported hosts are Cryptomeria japonica (Cupressaceae) and Abies firma (Pinaceae) (Fukuda and Hijii, 1997).

Based on 53 field-collected specimens, the earliest and latest capture dates are May 30 and August 11. Fukuda and Hijii (1997) published their work under the name X. spectrum. Most likely their specimens refer this species, the most common species in Japan. In Japan, X. spectrum is very rare. Contrary to X. spectrum in Europe with only one major emergence period in late June, Fukuda et al. (1997) has shown that X. malaisei has two major and isolated emergence periods, in mid-May (late April to late June, N = about 225) and mid-August (August to late September, N = about 168) (C8.4).



CHINA (Jilin – Northeastern region). JAPAN (Hokkaido, Honshu). RUSSIA (Primorsky kray). SOUTH KOREA. TAIWAN (high elevation). Xeris malaisei has been intercepted at several ports. In United States, most intercepted specimens (6) originated from Japan and were recorded at ports on both coasts (California: Long Beach, Los Angeles, San Diego; Georgia: Savannah; Louisiana: Baton Rouge) and one specimen intercepted in New Orleans, Louisiana could have originated from China. In New Zealand all specimens (7) were intercepted from both islands (Dunedin, Napier and Wellington). The intercepted specimens came from crates pine cable drums, Cryptomeria japonica dunnage (a favorite host tree in Japan Fukuda and Hijii (1997)), and wood products.


Specimens studied: 44 females and 42 males from ANIC, CNC, FRNZ, NSMT, SDEI, and USNM.


Specimens for molecular studies: 8. See Fig. D1.2d. For each specimen the following is recorded: country, year, state/province, specimen code (in italics), and number of base pairs.


JAPAN: CBHR 1001, 658; CBHR 1002, 658; CBHR 1003 658; S79, 658; S10, 658; S92, 658; S218b, 658; S491, 658.

None of the subspecies proposed by Maa (1949) are retained. There is no evidence of gene flow between any of Maa’s subspecies of X. spectrum. All of them, except X. spectrum townsei Maa, a junior synonym of X. indecisus (Schiff et al. 2012) differ constantly in color pattern and structures. See “Taxonomic notes” under each of the mentioned names for more information on color and structural differences. Xeris malaisei, a species originally from Taiwan, is widespread in northern China, Korea, Japan and extreme southeastern Russia. In the northern part of its range, X. malaisei is sympatric with X. spectrum. Xeris cobosi was not known to Maa (1949) but was included as a subspecies of X. spectrum by Viedma and Suárez (1961) and its status remained as such (Taeger and Blank 2011, Taeger et al. 2010). Xeris cobosi is related to but distinct from X. himalayensis. Xeris spectrum is distinguished from X. pallicoxae in females by coxal color pattern and the distribution of a very small pit on each of the annuli anterior to typical annuli with larger pit before teeth annuli, in males by the color pattern of the mesotarsomere 1 (usually), and in both sexes by the sculpture on the marginal yellowish-white band of the pronotum (the most easily evaluated character state) and the vertical lateral surface of the pronotum, and by the sculpture on the lateral and ventral surfaces of the propleuron. Xeris spectrum is distinguished from X. malaisei in females by the shape of fore wing vein 2A and the flagellum color pattern and in males by coxae and tarsi color. The North American populations considered till recently as X. spectrum spectrum are specifically distinct from X. spectrum and consist of two very similar species, X. caudatus and X. melancholicus (Schiff et. al., 2012). These two American species are distinguished from X. spectrum in females on coxal color pattern, the distribution of annular pits on annuli anterior to the apical annular group of major pits, in males on tibial color pattern at base (best seen on metatibia), and in both sexes on the dark brown base of stigma at junction with vein 1r-rs and the yellowish-brown fore wing cell C, and on pit size and abundance on gena between eye and genal ridge.


Xeris umbra, X. xanthoceros and X. xylocola, though more darkly colored, are related to X. spectrum and X. malaisei because of the presence of an extremely small pit on each of the basal annuli. X. umbra, the darkest species of Xeris, is distinguished from X. spectrum in both sexes by the size of setae on the clypeus and the leg color pattern, in females by the sculpticells centrally on tergum 8 and the teeth size in apical 0.3 of the cornus, in males by the almost completely or completely black legs. X. xanthoceros and X. xylocola are distinguished from X. spectrum in both sexes by the narrow shiny surface medially on the pronotum in dorsal view, and the mainly black pronotum in dorsal view, and in females by the light reddish-brown flagellum in apical 0.5–0.7.


Finally, the user should be aware that the refences based on European specimens could refer to X. spectrum, X. pallicoxae, or both species.


Geographical variation


Adults of X. spectrum show one difference in color pattern between Europe and the far eastern regions of Asia. Near the Pacific coast, the few females studied have completely black coxae. We cannot evaluate this color change as we did not have access to specimens between Europe and the Pacific coast drainage area. The change may be restricted to the Pacific drainage area or it may gradually change across Russia.


Hosts and phenology


We studied 291 specimens (BMNH) of X. spectrum collected by P. J. Spradbery and A. A. Kirk between 1963 and 1970. Each specimen’s label includes the name “Frank Wilson” who did not collect the specimens but supervised the rearing program sponsored by the Australian government. This is only a portion of about 6205 specimens of X. pallicoxae and X. spectrum collected by them.


The results of the emergence period and the host range published (Spradbery and Kirk 1978) is based on a mixture of specimens of X. pallicoxae and X. spectrum. Their emergence period of “X. spectrum” was based on specimens from Turini in southeastern France. We saw about 35% (67 specimens) of their Turini sample. This sample consists of 79% X. pallicoxae and 21% X. spectrum. Most specimens of X. spectrum are from central and northern Europe so we pooled 284 specimens to determine phenology. The emergence cycle started in late May and ended in late July with only one clear emergence peak in late June (C12.8). These results are similar over the years, but there could be a general shift of one week either way. Xeris pallicoxae in contrast shows two emergence peaks during the same period with two clear peaks, one in early June and another in late June, and a very small emergence in late summer.


Xeris spectrum has a moderately wide host range within Pinaceae. Based on 150 specimens (20% of specimens at the BNMH) from Spradbery and Kirk, X. spectrum was reared from Abies alba (fir) and Picea abies (spruce). Amazingly, 90% of specimens were reared from Picea abies. This may reflect a relatively greater abundance of spruces than firs in some of the sites sampled by Spradbery and Kirk rather than a marked preference of X. spectrum for spruce. Spruces are common north of France and very uncommon in the Mediterranean region, based on their known distribution and their samples host data (Spradbery and Kirk 1978).  Spradbery mentioned other hosts, but we are not sure yet if they should be assigned to X. spectrum. Except for intercepted specimens from New Zealand and the United States (acronym given in square brackets), the following published data under X. spectrum almost certainly includes specimens of X. pallicoxae. The hosts are Pinaceae: Abies sp. [FRNZ], A. alba (Enslin 1918, Spradbery et al. 1978), A. borisii-regis (Spradbery et al. 1978), A. cilicia (Spradbery et al. 1978), A. equi-trojan (Spradbery et al. 1978), Larix decidua (Spradbery et al. 1978), Picea sp. [FRNZ], P. abies (Enslin 1918, Spradbery et al. 1978) [FRNZ, USNM], P. orientalis (Spradbery et al. 1978), P. sitchensis (Spradbery et al. 1978), Pinus sp. [FRNZ], P. pinaster (Spradbery et al. 1978), and P. sylvestris (Enslin 1918, Spradbery et al. 1978).

Spradbery and Kirk (1978) listed parasitoids associated with larvae of X. spectrum and almost certainly those of X. pallicoxae. They included Ibalia leucospoides leucospoides (Hochenwarth), I. rufipes drewseni (Borries) (Ibaliidae ) and Megarhyssa emarginatoria (Thunberg), Rhyssa persuasoria (Linnaeus), and R. amoena (Gravenhorst) (Ichneumonidae).





Benson (1955) reports a specimen from Israel emerged from pine timber imported from Yugoslavia (Benson, 1955). Eastern Asia: Japan, Russia. Xeris spectrum has a transpalaearctic range from Scandinavia to easternmost Russia and Japan (apparently very rare). In Europe it is known as far south as Spain, Italy, and Hungary. Most specimens seen were north of France and Switzerland. The species no doubt occurs in northern China (Maa 1949) but we have not seen specimens.


Numerous specimens of Xeris spectrum have been intercepted at ports in the United States (7) and New Zealand (14) from the following European countries: Belgium (United States and New Zealand), Germany (United States and New Zealand), Italy (United States), Netherlands (New Zealand), Poland (United States), Russia (Japan), Switzerland (New Zealand), Turkey (United States). The species is not established outside Europe.

Specimens studied: 195 females and 250 males from BMNH, CNC, NMST, SDEI, SDEI – Col. E. Jansen, USNM, and ZMUN.


Specimens for molecular studies: 16 specimens. See Fig. D1.2d. For each specimen the following is recorded: country, year, state/province, specimen code (in italics), and number of base pairs.


EUROPE. Austria: S69, 658. Germany: 1975, S64, 658; 1977, S216, 658; 1977, S272, 658; 1977, S274, 658; 1977, S342, 658; 1978, S355, 658; 1977, S373, 658; 1977, S376, 658; 1977, S464, 658. France: 1978, S220, 658. Italy: 2005, CBHR 41, 658; 1978, S235, 658. Japan: 1977, S375, 658. Netherlands: 2007, CBHR 1090, 658. Russia (eastern): SIR 161.


EUROPE. Austria: S516, 631. Belgium: 1975, S65, 658. France: 1978, S293, 658; 1977, S497, 658. Germany: 1979, S68, 658; 1977, S473, 658; 1978, S179, 658; 1978, S198, 658; 1977, S269, 658; 1978, S296, 658; 1977, S344, 658; 1977, S347, 658; 1978, S394, 658; 1978, S426, 658; 1981, S442, 658; 1977, S474, 658; 1977, S487, 658. Italy: 1971, S76, 658; 1972, S82, 658; 1973, S126, 658; 1977, S264, 658.