ISSN 1911-2173
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

11. Xeris pallicoxae Goulet n. sp.

Fig. C11.1 (female habitus)

Fig. C11.2 (male habitus)

Xeris spectrum; auctorum (in part) (not Linnaeus, 1758: 560 only for European records).

Type material

Holotype female (SDEI), in perfect condition, labelled [White label] “14.vii.1996 D, BW WT, Wehrhalden Kirchspielwald, Schwarze Säge-Markstein, E. Jansen leg.”; [White} “Xeris specrum (Linnė) ♀ E.Jansen det. ’97”;[White] “Ex coll E. Jansen”; [Red] “HOLOTYPE Xeris pallicoxae ♀ H. Goulet, 2011”.

Paratypes. 337 females and 670 males. ALGERIA: [probably mislabeled] (1 M, BMNH). AUSTRIA: Kämten Waidischtal near Ferlach (2 M, Col. E. Jansen); Lower Austria, Lunz am See, 47.86˚N 15.03˚E (2 F, SDEI; 1 M, USNM) Paznautal (1 F, BMNH); Tyrol (1 M, BMNH). BELGIUM: Bois de Roi, Exp. 163(5) (1 F, BMNH). BULGARIA: Borovetz, Exp. 197(5) (2 F, BMNH). CZECH REPUBLIC: Bohemia, Chodau (6 F, 1 M, BMNH) ; Hodruso, Exp 601(6) (2 M, BMNH); Orličky – N Sucky VRCH 980 M NN (3 M, SDEI – Col. E. Jansen); Dobříš (1 F, 1 M, NSMT). CROATIA: Fusine, (Holzlagerplatz) and vicinity (2 F, SDEI). DENMARK: intercepted in New Zealand, Auckland (1 F, FRNZ). FRANCE: Auvergne. Dép., Haute Loire, Le Bouchet-bas, Les Roches (1 F, Col. E. Jansen) ; Cantal R. Alagnon, Le Lioran (1 M, BMNH); Cisai, Exp(3) (2 F, 2 M, BMNH); Forêt de Belleme, Exp. 176(5) (13 F, 17 M, BMNH); Forêt d’Ecouves, Exp. 175(3) (3 F, 5 M, BMNH); Le Boreon, Exp. 103(3), (5 F, 27 M, BMNH); Montfort sue Risle 49º18.503’N 0º40.887’E (1 F, 2 M, USNM); St. Jean de Mont, Exp 148(7) (1 F, BMNH); Turini, Exp. 148(7) (1 F, BMNH); Turini, Exp. 105(4) (6 F, 45 M, BMNH); Turini, Exp. 106(5) (1 F, BMNH); Turini, Exp. 195(4) (1 F, 2 M, BMNH); Vosges, Exp. 193(6) (11 F, 18 M, BMNH); Corsica, D’Aitone, Exp. 1208 (1 F, 11 M, BMNH); intercepted in USA, KS, Kansas City (1 F, USNM); intercepted in USA, CA, Long Beach (1 F, USNM); intercepted in USA, TX, Houston (1 F, USNM); intercepted in New Zealand, Invercargil, Aluminium Smelter Bluff (12 F, 9 M, FRNZ). GERMANY: Ebesberger, Exp. 126(4) (2 F, 1 M, BMNH); Fallingbostel, Exp. 117(8) (1 F, BMNH); Forstamt Rantzeau, 128(3) (1 M, BMNH); Gahrenburg, Exp. 116(4) (2 F, BMNH); Baden Württemberg, Ottenhöfen 7415 NW Eichhaldenfirst 570 (1 M, SDEI [Müncheberg HYM-00151]); Thuringia, Friedrichroda, 50.87˚N 10.57˚E (1 F, SDEI; 1 M, USNM); Baden Württemberg, Schönmünzack (1 F, SDEI); Gomaringen near Tübingen (1 M allotype, SDEI) ; intercepted in USA, AL, Mobile (1 F, USNM); intercepted in USA, PA, Philadelphia (1 F, 2 M, USNM); intercepted in USA NY, New York (1 F, USNM); intercepted in USA, NC, Monroe (2 F, USNM); intercepted in USA, LA, New Orleans (1 F, USNM); intercepted in Puerto Rico, Ponce (1 F, USNM); intercepted in New Zealand, Auckland (1 F, FRNZ). ?GERMANY: Rossberg near RT (1 M, SDEI); vicinity of Feldkirch Mossbrugger (2 M, SDEI); Sud-Vogesen (1 M, SDEI); Germsbach (2 M, SDEI); Erzgebirge Lange (1 F, USNM). GREECE: Agios, 676 (1 F, 2 M, BMNH); Elari, Exp. 673 (5 F, 4 M, BMNH); Evia, Exp. 675 (2 M, BMNH); Glyfada, Exp. 669 (1 M, BMNH); Granitis, 669 (6 F, 3 M, BMNH); Parnis, 674 (3 F, 1 M, BMNH); Pertouli, 672 (2 F, 8 M, BMNH); Attika, Parnis Oros, 38.17˚N 23.67˚E (1 F, SDEI); Parnassos massif, 38.53˚N 22.62˚E (1 F, SDEI). HUNGARY: Retyezáth, 300– 400 m (1 F, BMNH); [locality unknown] (1 M, SDEI). ITALY: Bibbiena, 190(4) (1 F, 1 M, BMNH); Bolzano, 192(4) (1 M, BMNH); Camaldoli, Exp 188(4) (16 F, 26 M, BMNH); F. Campiggna (1 F, BMNH); Lama, Exp 115(4) (23 F, 86 M, BMNH); Pratovecchio, 114(4) (40 F, 26 M, BMNH); Sabaudia, Exp. 187 (1 F, BMNH); Uimbra, Exp. 677 (1 F, 1 M, BMNH); unknown locality, Exp. 238 (6 F, 2 M, BMNH); Calabria, Alt. 1850 m, Paganetti (4 M, SDEI); intercepted in USA, LA, New Orleans (1 F, USNM); intercepted in USA, CA, Long Beach (1 F, USNM); intercepted in USA, GA, Savannah from (5 M, USNM); intercepted in USA, CA, Auckland (2 F, 1 M, USNM); intercepted in USA, NY, New York (1 M, USNM); intercepted in USA, TX, Houston (1 M, USNM). NETHERLANDS: intercepted in USA, NY, New York (1 M, USNM). NORWAY: Mordmarker, Exp. 143(9) (1 M, BMNH). POLAND: Schlesien (1 M, SDEI); Szczawa, 49˚36’N 20˚18’E (8 F, USNM). ROMANIA: Transylvania (1 F, SDEI); intercepted in USA, TX, Houston (1 F, USNM). SCANDINAVIA: [country unspecified] intercepted in England (3 F, BMNH). SLOVAKIA: Pieninsky Nat. Park (1 F, SDEI).  SWITZERLAND: Chatillon, Exp. 31(F) (1 F, BMNH); Chatillon, Exp. 36 (1 F, BMNH); Chatillon, Exp. 224 (1 F, BMNH); Corbières, 110(4) (1 M, BMNH); Grison, Engadine (1 F, BMNH); Le Noir Bois, Exp. 172(6) (3 F, 2 M, BMNH); Lucelle, Exp. 173(7) (7 F, 10 M, BMNH); Lucelle, Exp. 196(7) (1 F, 7 M, BMNH); Riaz, Exp. 109(5) (1 M, BMNH): unknown locality, Exp. 229 (29 F, 95 M, BMNH); unknown locality, Exp. 224 (3 F, 5 M, BMNH); unknown locality, Exp. 332 (1 F, BMNH); intercepted in New Zealand, Auckland (1 M, FRNZ). TURKEY: Bulgaz, Exp. 664 (1 F, 3 M, BMNH); Bulgaz, Exp. 665 (5 M, BMNH); Cangal Kastmanu, Exp. 656 (1 M, BMNH); Eqner Karsanti, Exp. 667 (9 F, 16 M, BMNH); Namrun Mersin, Exp. 664 (1 F, 4 M, BMNH); Santa Trabzan, Exp. 655 (1 M, BMNH); Sogur Karsanti, Exp. 665 (7 F, 10 M, BMNH); Urgulu Bucak, Exp. 662 (1 F, 1 M, BMNH): Uludag, Borsa, Exp. 658 (2 F, BMNH); Zigana Dagi, 1500–1800 m (3 F, BMNH). UNITED KINGDOM: England, Essex, Harrowich (1 F, BMNH); Hampshire, Romsey, Aubridge, Ex Larix (0 F, 67 M, BMNH); Oxfordshire, Nuneham Park, Ex Pinus sylvestrix) (2 F, BMNH); Britain (1 F, BMNH); Wales, Cynwyd, Exp. 178(7) (2 M, BMNH). YUGOSLAVIA: Belasica, Exp. 123(4) (1 F, BMNH); Brezna, Exp. 604(2) (3 F, 1 M, BMNH); Crni Lug, Exp. 141(5) (4 F, 2 M, BMNH); Dobra Voda, Exp. 604(2) (1 F, 8 M, BMNH); Hurbache, Exp. 134(2) (1 F, BMNH); Kraljevo, Exp. 132(3) (1 F, BMNH); Mavrovi, Exp. 125(3) (2 F, 3 M, BMNH); Mokopaly, Exp. 140(4) (3 F, 1 M, BMNH); Toliscina, Exp. 121(2) (4 F, 2 M, BMNH); unknown locality, Exp. 228 (2 F, 3 M, BMNH); unknown locality, Exp. 246(a), 246(B), 246(C) (15 F, 77 M, BMNH); intercepted in New Zealand (1 M, FRNZ). Europe: intercepted in New Zealand (1 F, FRNZ); [unknown country] (2 F, BMNH). Unknown: intercepted in New Zealand, Auckland (1 F, FRNZ). One specimen intercepted in Malta reported from Bombay, India is no doubt incorrect (1 F, BMNH).

Diagnostic combination

Among specimens with small and more scattered pits between dorsoposterior edge of eye and occiput outside postocellar area, with a yellowish-white fore wing cell C, and with short setae on the head (0.6–0.7 as long as diameter of a lateral ocellus ) [pallicoxae, malaisei, spectrum, xanthoceros and xylocola], X. pallicoxae is recognized in both sexes by the smooth surface between large teeth on the white longitudinal band of the pronotum and by the white base of stigma on both sides of junction with vein 1r-rs, in females by the black antenna and mainly reddish-brown coxae, and in males by the light reddish-brown tarsomeres 3–5 and by the narrow reddish-brown transverse band at the apex of mesotarsomere 1 (narrower than basal pale band).

Description

FEMALE

Color. Head black except for small white spot on gena dorsal to middle of eye; white spot usually clearly outlined and not extending down to genal ridge (Fig. C11.3); antenna black; last maxillary palpomere reddish brown (Fig. C11.3). Thorax black except for white longitudinal band extending from posterolateral to anterolateral angles including vertical portion of anterior angle, the band 0.4 times as wide as 0.5 lateral width of pronotum and extending to lateral margin of pronotum (only apex of teeth black along pronotal edge) (Fig. B2.94). Legs including coxae light reddish brown (coxae very narrowly black at anterior or anterior and posterior dorsal edges, rarely a little more on ventral surface) (Fig. B2.98). Fore wing clear except for lightly tinted band in apical 0.25, and on posterior corner of cells 2CU and 3CU (as in Fig. B2.67); costal cell light yellow (paler in old specimens) (Fig. B2.40); most of area ventral to anal cells yellowish brown; veins black (but veins C and R black, but base of veins C and R, and base of stigma on both sides of junction with vein 1r-rs contrastingly white (Fig. B2.40). Abdomen black (Fig. C11.1). 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. Eye in lateral view (N = 20) with its maximum height 1.24–1.58 times as long as its maximum length (as in Fig. C11.3), and maximum height of eye 0.42–0.51 times as long as maximum height of head (from transverse ridge on gena above mandible to top of head) (Fig. C11.3, 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 B2.43) (in frontal view outer edges of eyes clearly not intersecting genae, measurements as in Figs. B2.5); in lateral view with distance between outer edge of eye and genal ridge 0.32–0.64 times as long as maximum length of eye (Fig. C11.3), with few or no pits ventral to genal ridge, 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) (Fig. C11.3). Transverse ridge above mandible narrow, sharp and mainly smooth (Fig. C11.3). Vertex scarcely pitted and pits medium in size (diameter of pit 0.2–0.35 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 gutter-like median furrow but a little more widespread near lateral ocelli (as in Fig. B2.43).

Thorax. Pronotum in dorsal view along yellowish-white longitudinal band smooth between large teeth (Fig. B2.94) and in lateral view without coarse polygonal pits or with very few pits on 0.1 of posterior surface (Fig. B2.96). Propleuron in lateral view basically without pits but with tooth-like projections sometime fusing anteriorly with other teeth and not forming coarse pits (Fig. C11.5); in ventral view generally with scattered shallow small 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 (Fig. C11.8). Fore wing in middle 0.3 of vein 2A diverging very rarely slightly (Fig. C11.6) to usually considerably (as in Fig. C12.6) away from wing edge and then more (Fig. C11.6) or less (as in Fig. C12.6) abruptly curved away from wing edge; vein 3A absent (29%), reduced to a stump (32%), extending slightly as a short nebulous vein (21%), and extending along posterior margin of wing (18%) (N = 34).

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; N = 3) 0.7–1.0 times as wide as its median length, with maximum width of basin 1.6–2.0 times as wide as its median length, and basin 0.3–0.5 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 0.21–0.35 times as long as apical section (N = 44) (Fig. C11.1); 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 22–32 annuli (first 15 annuli hard to see, but still outlined; N = 14); junction of basal and apical sections of sheath aligned between 3rd–4th annuli; major pits present on last 4–5 apical annuli before teeth annuli, and without a pit on each of the preceding annuli (Fig. C11.7).

MALE

Color. Head with dorsal spot behind eye clearly outlined, larger than in female, and extending to genal ridge (Fig. C11.4). Coxae black; trochanter partly to completely reddish brown; femora reddish brown to black; tibiae whitish yellow in basal 0.3 and sharply outlined, protibia light reddish brown with a wide longitudinal band on outer margin in apical 0.5 or with black transverse band in apical 0.5, mesotibia light reddish brown with black transverse band in apical 0.6, and metatibia except at base black; tarsi light reddish brown except for black dorsal longitudinal band on mesotarsomere 2 (rarely all black) (Figs. B2.101 and C11.2); metatarsomere 1 yellowish white at base and narrowly reddish brown at apex (rarely black on pro- and mesotarsomeres 2 and almost never on tarsomeres 3), and with brown or black central transverse band or cloud on metatarsomere 2  in most specimens. (Figs. B2.101 and C11.2).

Thorax. Metatibia with shallow notch on dorsal edge in basal 0.25 (Figs. B2.101 and C11.2).

Taxonomic notes

We were surprised to uncover an undescribed European species under X. spectrum. This was the result of a detailed study of the American species known traditionally as X. spectrum spectrum, (see “Taxonomic notes” under X. caudatus). Females of X. pallicoxae are separated from those of X. spectrum on color of coxae, and on the absence of a small pit on each of the annuli anterior to the typical group of subapical annuli with larger pit, males on the color pattern of mesotarsomere 1 and metatarsomere 1, and both sexes on the lack or almost lack of coarse pits on the vertical surface of the pronotum in lateral view, on the sculpture on the lateral surface of the propleuron and on the lack of  microsculpture between large teeth along the longitudinal yellowish-white band on the pronotum.

            When everything looks straight forward, complications show up. The DNA barcode neighbor-joining tree of X. pallicoxae may consist of two species named here “Type 1” and “Type 2” (see Figs. D1.2e and discussion under “Mitochondrial DNA results”). The sequences are based on larvae (USNM) and there is a divergence of 2.2% between the two groups of DNA barcodes. In the analysis of the main emergence cycle of X. pallicoxae we noted the unusual two adult emergence peaks one in early June and another in late June (see Fig. C11.9). Normally a species emergence consists of one peak over a one month period in studied Siricidae (Schiff et al., 2012). Therefore, the two peaks in adult emergence is a clue supporting the DNA barcode results. We are unable to assign the name X. pallicoxae to either type as the data is based on larvae. Fresh adults for barcoding are needed to associate them with the larval barcodes and eventually find morphological differences to distinguish the adults.

Origin of specific epithet

The specific name “pallicoxae” means “pale coxae” characteristic of females of this European species.

Geographical variation

We noted no geographical differences among females of Xeris pallicoxae over its range. However, males show a pattern. The metafemur color varies from reddish brown to black. In Central Europe and on the island of Corsica (France) a black metafemur is the dominant color. Elsewhere between France and Turkey in the Mediterranean region, a reddish-brown metafemur dominates. In Italy, specimens with intermediate color pattern are common. However at the extreme eastern portion of the X. pallicoxae range in Turkey, specimens with intermediate color pattern are uncommon.

Hosts and phenology

We studied 822 specimens (BMNH) of X. pallicoxae 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 specimen but supervised the rearing program sponsored by the Australian government. This is only a portion of about 4000 specimens collected by them.

The published result of the emergence period and the host range (Spradbery and Kirk 1978) is a mixture of specimens of X. pallicoxae and X. spectrum. Their emergence period was based on specimens from Turini in southeastern France. We saw about 35% (87 specimens) of their Turini sample. This sample consists of 79% X. pallicoxae and 21% X. spectrum. Comparing results of the emergence distribution from Central Europe with that from Mediterranean Europe including Turkey, we found that emergence starts in mid-May along the Mediterranean region and in late May in Central Europe. In both regions there are two clear emergence peaks in spring. Based on 571 specimens, the first peak occurs in the first week of June and the second in the last week of June (Fig. C11.9). The major emergence period is followed by a very small emergence in late September and early October. These results are similar over the years, but there could be a general shift of one week either way. In contrast, Xeris spectrum shows only one emergence period, with a single peak in late June.

One sample from Hampshire, England, collected from a Larix bole was unusual because of the size difference between specimens emerged from the first and second year after the tree was cut down. Specimens from the first year (N = 40 males) were clearly smaller than those of the second year (N = 27 males). The maximum head width in dorsal view was 2.7 mm (standard deviation = 0.22; range 2.1–3.2 mm) for the first year and 3.7 mm (standard deviation = 0.35; range 2.1–4.2 mm) for the second year. Four specimens from the second year were well within the range of those of the first year sample (2.1–3.0) whereas all other specimens were greater than 3.3 mm. Xeris females do not carry fungi within their reduced mycangia. Therefore, a possible hypothesis is that specimens of X. pallicoxae from the first year sample were in competition for the fungus (brought previously by females of Urocerus and/or Sirex) with larvae of Urocerus and/or Sirex, whereas those of the second year with lower numbers of larvae would have most of the fungus to themselves.

Xeris pallicoxae has a moderately wide host range within Pinaceae. Based on 20% of specimens at the BNMH (162) collected by Spradbery and Kirk, X. pallicoxae was reared from a wide variety of firs (Abies alba, A. borisii-regis, A. cilicica, and A. bornmuelleriana), spruce (Picea abies) and and Pine (Pinus radiata). Spradbery and Kirk (1978) reported X. spectrum from A. equi-trojan in Greece where we have seen only X. pallicoxae. Amazingly, 97% of specimens were reared from firs. This may reflect a relatively greater abundance of firs than spruces in sites sampled by Spradbery and Kirk rather than a marked preference of X. pallicoxae for firs. Spruces are very uncommon in the Mediterranean region based on their known distribution and their sample’s host data (Spradbery and Kirk 1978).

Range

EUROPE: AUSTRIA, BELGIUM, BULGARIA, CZECH REPUBLIC, CROATIA, DENMARK, FRANCE (continental), FRANCE (Corsica), GERMANY, GREECE, HUNGARY, ITALY, NETHERLANDS, NORWAY, POLAND, ROMANIA, SLOVAKIA, SWITZERLAND, TURKEY, UNITED KINGDOM, and YUGOSLAVIA. Xeris pallicoxae is a widespread European species from Denmark and Poland south to Italy and from France to Turkey, and most captured specimens south of Germany belong to this species.

Numerous specimens of Xeris pallicoxae have been intercepted at ports in the United States (22) and New Zealand (27) from the following European countries: Denmark (New Zealand), France (United States and New Zealand), Germany (United States, New Zealand and Puerto Rico), Italy (United States), Romania (United States), Switzerland (New Zealand), and Yugoslavia (New Zealand). The species is not established outside Europe.


Specimens studied: 314 females and 603 males from BMNH, CNC, EIHU, SDEI, SDEI – Col. E. Jansen, and USNM.

Specimens for molecular studies: 21 specimens. See Fig. D1.2e. For each specimen the following is recorded: country, year, state/province, specimen code (in italics), and number of base pairs.

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.