Dibrachys microgastri Bouche 1834
Creators: name: Peters, Ralph S.
name: Baur, Hannes
Publisher: name: Zenodo
Year: 2011
Subjects: Biodiversity
Taxonomy
Animalia
Arthropoda
Insecta
Hymenoptera
Pteromalidae
Dibrachys
Dibrachys microgastri

description: Dibrachys microgastri (Bouché, 1834)
(Figs 7a, 7 d, 8a, 8d, 9a, 9d)
Diplolepis microgastri Bouché, 1834: 168, neotype female in ZMH, present designation. Syntypes presumed lost (see Graham, 1969: 811).
Pteromalus cavus Walker, 1835: 477 –478, lectotype female in BMNH (B.M. TYPE no. 5.2987), designated by Graham (1969: 811) (examined by Peters); syn. n.
Pteromalus decedens Walker, 1835: 478, lectotype female in BMNH (B.M. TYPE no. 5.2988), designated by Graham (1969: 811) (examined by Peters); synonymized with D. cavus by Graham (1956: 261, but see also Graham, 1969: 811); syn. n.
Pteromalus albinervis Ratzeburg, 1844: 199, name-bearing types presumed destroyed (see comment of Graham (1969: 811) for P. tenuis Ratzeburg, 1844 and P. boucheanus Ratzeburg, 1844); synonymized with D. boucheanus by Kurdjumov (1913: 11); syn. n.
Pteromalus boucheanus Ratzeburg, 1844: 196, name-bearing types presumed destroyed (Graham, 1969: 811); Dibrachys boucheanus, combination by Thomson (1878); synonymized with D. cavus by Gahan (1938: 211); syn. n.
Pteromalus boarmiae Walker in Newman, 1863: 8609 –8610 (English description accidentally transposed, see comment of Graham (1969: 812)), lectotype female in BMNH (B.M. TYPE no. 5.2989), designated by Graham (1969: 812) (examined by Peters); syn. n.
Pteromalus tenuis Ratzeburg, 1844: 195, name-bearing types presumed destroyed (Graham, 1969: 811); synonymized with P. boucheanus by Ratzeburg (1848: 189); syn. n.
Pteromalus zelleri Ratzeburg, 1848: 190, name-bearing types presumed destroyed (see comment of Graham (1969: 811) for P. tenuis Ratzeburg, 1844 and P. boucheanus Ratzeburg, 1844); synonymized with D. boucheanus by Kurdjumov (1913: 11); syn. n.
Pteromalus vesparum Ratzeburg, 1852: 233, name-bearing types presumed destroyed (see Graham, 1969: 809); synonymized with D. boucheanus by Kurdjumov (1913: 11); syn. n.
Cleonymus clisiocampae Fitch, 1856: 431 –432, syntype female and male in USNM (USNM type no. 1831) (examined by Peters); synonymized with D. cavus by Gahan (1938: 211), but considered valid by Doganlar (1987: 204); syn. n.
Cheiropachus nigrocyaneus Norton, 1869: 327, syntype females in USNM (USNM type no. 61079) (examined by Peters); Pachyneuron nigrocyaneum, combination by Ashmead (1888); synonymized with D. clisiocampae by Girault (1916b: 408), with D. cavus by Gahan (1938: 211), and subsequently with D. clisiocampae by Doganlar (1987: 204); syn. n.
Eupelmus cereanus Rondani, 1876: 38, 40, lectotype female in MZUF (no. 32), designated by Bouček (1974: 247) (examined by Peters); synonymized with D. cavus by Delucchi (1955: 174); syn. n.
Pteromalus gelechiae Webster, 1883: 151, lectotype male in INHS (INHS Insect Collection 213,068), designated by Frison (1927: 220) (examined by Peters); nine paralectotypes in INHS (one female labeled “lectoallotype”, INHS Insect Collection 213,069; four males and four females labeled “ paratypes ”, INHS Insect Collection 257,879–257,886) (examined by Peters); synonymized with D. clisiocampae by Girault (1916b: 408), with D. cavus by Gahan (1938: 211), and subsequently with D. clisiocampae by Doganlar (1987: 204); syn. n.
Pteromalus chionobae Howard, 1889: 1889, syntypes in USNM (USNM type no. 2673) (examined by Peters); synonymized with D. clisiocampae by Girault (1916b: 408), with D. cavus by Gahan (1938: 211), and subsequently with D. clisiocampae by Doganlar (1987: 204); syn. n.
Arthrolytus apatelae Ashmead, 1893: 162, syntypes in USNM (USNM type no. 26215 examined by Peters); Dibrachys apatelae, combination by Girault (1916b); synonymized with D. cavus by Gahan (1938: 211), and with D. clisiocampae by Doganlar (1987: 204); syn. n.
Arthrolytus pimplae Ashmead, 1894: 339, syntypes in USNM (USNM type no. 2182) (examined by Peters); synonymized with Arthrolytus apatelae by Girault (1916a: 297; 1916b: 408), with D. cavus by Gahan (1938: 211), and with D. clisiocampae by Doganlar (1987: 204); syn. n.
Trichomalus truyilloi Blanchard, 1938: 178, name-bearing types unknown; synonymized with D. cavus by Gahan (1942: 45); syn. n.
Tritneptis elegans Szelényi, 1981: 178, holotype female in HNHM (Hym. Typ. nr. 6821) (examined by Peters); assigned to Dibrachys by Bouček & Rasplus (1991); syn. n.
Diagnosis. Both sexes. Eyes large, eye height greater than 2.0x POL. Head and mesosoma mostly with distinct metallic coloration, predominantly green or dark green (Figs 7a, 7 d, 8a, 9a), but sometimes distinctly blue or with distinct blue tinge on mesoscutum.
Female. Gaster long and eyes elongate, gaster length usually greater than 4.05x eye breadth (3.88–5.43, but only 6 of 114 ≤ 4.05) (Figs 6, 7a, Table 7). Outer margin of eyes straight or slightly to distinctly emarginate (Fig. 7a). Stigmal vein short compared to marginal vein, marginal vein usually 2.0x or more stigmal vein (1.62–2.86, but only 11 of 121 <2.0) (Fig. 8 d). Mouth narrow, head breadth greater than 2.0x mouth breadth (Fig. 7 d).
Male. Scape and pedicel apically both without lobe on outer side (Fig. 9 d). Gastral spot absent to distinct (Fig. 9a).
group min. 1st quartile median 3rd quartile max. N lignicola 3.54 3.63 3.73 3.87 4.05 44 cavus 3.88 4.50 4.72 4.90 5.43 113
head breadth / stigmal vein
group min. 1st quartile median 3rd quartile max. N lignicola 3.46 3.94 4.16 4.32 4.73 44 cavus 3.71 4.40 4.69 5.06 5.83 113 Description. FEMALE (Figs 7a, 7 d, 8a, 8d). Body length 1700–2950 μm.
Head (Figs 7a, 7 d). Eyes large and elongate, sometimes kidney shaped, outer margin straight or slightly to distinctly emarginate; eye 1.39–1.83x as high as broad; eye height 2.05–2.59x POL. Level of lower margin of antennal toruli at level of lower ocular line. Clypeus distinctly striate vertically, though less distinct towards lower margin. Lower face only moderately receding. Mouth narrow, head breadth 2.04–2.83x mouth breadth, mouth breadth 1.73–2.95x malar space. POL 1.55–2.31x OOL. First anellus transverse, second anellus slightly longer than broad; first funicular segment slightly longer than broad, second to fifth quadrate, and sixth slightly transverse; flagellum 0.61–0.80x head breadth.
Mesosoma (Fig. 8a). Mesoscutum and scutellum slightly convex in lateral view. Mesoscutum 0.46–0.68x as long as broad. Reticulation coarse, 11.7–14.5 meshes/200 μm in anterior part of mesoscutum, sometimes finer on scutellum than on mesoscutum. Marginal rim of scutellum only moderately turned upwards. Plicae weak and straight; median carina occasionally missing or interrupted.
Wings (Fig. 8 d). Wings hyaline; stigmal vein short, marginal vein 1.62–2.86x stigmal vein; submarginal vein 1.4–2.2x marginal vein.
Metasoma (Fig. 7a). Gaster varying from almost as long as to longer than head plus mesosoma; elongate and pointed; length 3.88–5.43x eye breadth. Tergites smooth, weakly alutaceous in apical half of gaster and with strong hairs, especially in apical half; sternites with few hairs.
Hypopygium. See Table 8 (characters used by Doganlar 1987).
Color (Figs 7a, 7 d, 8a, 8d). Head and mesosoma very variable, but head and dorsal surface of mesosoma always with distinct metallic coloration or black with distinct metallic tinge. Antenna varying from yellow to dark brown. Ventral surface of mesosoma black or dark brown with slight metallic tinge or with distinct metallic coloration. Venation of wings testaceous to distinctly brown. Procoxa usually concolorous with mesosoma; meso- and metacoxa sometimes concolorous with mesosoma, but mostly brown. Trochanters, femora and tibiae varying from yellow to dark brown. Tarsi varying from pale yellow to brown, segments 4 and 5 of metatarsus usually darker than others. Gaster dark brown and shiny.
MALE (Figs 9a, 9 d). Similar to female except as follows. Smaller, body length 1450–2360 μm.
Head. Eyes not emarginate and more circular in shape; eye height 2.11–2.60x POL. Level of lower margin of antennal toruli slightly above lower ocular line. Scape and pedicel apically without lobe on outer side.
Metasoma. Gaster distinctly shorter than rest of body, 0.63–0.93x length of head plus mesosoma; elongate, not distinctly pointed, broader than in female.
Color. Head always with distinct metallic coloration. Antenna varying from yellow to brown, clava sometimes a little darker than rest. Mesoscutum always with distinct green or blue metallic coloration; scutellum often with distinct bronze or gold-bronze. Coxae usually brown, sometimes at least in part concolorous with mesosoma. Gaster brown with light testaceous spot on ventral side of anterior segments (“gastral spot”) absent to distinct, and if distinct then also visible in dorsal view.
Material examined. Neotype female (hereby designated): Germany: Schleswig-Holstein: Halstenbek, garden of Langkoppelweg 24, N53.6197 E9.8283 (WGS84), reared from cocoon of Cotesia glomerata (Hymenoptera: Braconidae), leg. L. Krogmann 26/04/2006, det. R. Peters 2009. Deposited at ZMH (A, 1 female).
Other material: Afghanistan: Chakav, labeled “Chakav, C.I.B.C.”, reared from “larva boring in branches of Juglans regia ” (A, 2 females) (BMNH) (det. Dibrachys sp.). Algeria: Delassus (?), reared from Lobesia botrana (A, 9 females, 3 males) (BMNH) (det. D. cavus). Australia: Victoria, reared from Galleria mellonella (A, 1 female) (BMNH) (det. D. boarmiae); Victoria, reared from Cydia molesta, originally identified as D. australia, Korr. Bouček (A, 2 females, 1 male) (BMNH) (det. D. boarmiae). Bulgaria: reared from Cephus sp. (A, 3 females) (BMNH) (det. D. cavus). Canada: British Columbia: Burnaby, reared from Eutromula pariana, leg. Doganlar 10/ 09/1977 (all 7 females A (ZSM 01–07), 3 males) (ZSM) (det. D. clisiocampae); British Columbia: Burnaby, reared from Apanteles longicauda, leg. 01/09/1977 (A, 1 female) (MDC) (det. D. clisiocampae); British Columbia: Burnaby, reared from Apanteles sp., leg. 30/08/1977 (1 male) (MDC) (det. D. boarmiae). Croatia: Rovinj, reared from Diptera puparium (8 females, 1 male) (ZMH) (det. D. cavus). Cyprus: reared from stored wheat (A, 9 females) (BMNH) (det. D. cavus); Nicosia, reared from Coleophora sp. (A, 1 female) (BMNH) (det. D. cavus). Czech Republic: Bohemia: Stepanov, reared from Diprion polytomum (= Gilpinia hercyniae) (A, 19 females) (BMNH) (det. D. cavus); Bohemia: Dobris, reared from Diprion polytomum (A, 3 females) (BMNH) (det. D. cavus); Bohemia: Dobris, reared from Diprion polytomum, different host specimen than previous, prob. different collection date than previous (18 females) (BMNH) (det. D. cavus); Bohemia: Holovousy, reared from tachinid puparium ex Cydia pomonella (A, 1 female) (BMNH) (det. D. cavus); Bohemia: Plese, reared from Diprion polytomum (11 females, 2 males) (BMNH) (det. D. cavus); Bohemia: Vlastijovice (?, probably wrong spelling), reared from Diprion polytomum (A, 9 females, 10 males) (BMNH) (det. D. cavus). Egypt: reared from Platyedra gossypiella (= Pectinophora gossypiella) (A, 1 female) (BMNH) (det. D. cavus); Kafr el Sheikh, reared from Galleria mellonella (7 females, 1 male) (BMNH) (det. D. boarmiae). England: no host, identified as D. fuscicornis by Walker, corrected by Bouček (A, 1 female) (BMNH) (det. D. cavus); Buckinghamshire, no host (A, 1 female) (BMNH) (det. D. cavus); Buckinghamshire, same location and different collection date than previous, no host (1 female) (BMNH) (det. D. cavus); Wiltshire: Salisbury, reared from Galleria melonella ex beehive (A, 1 female, 2 males) (BMNH) (det. D. cavus); no host (1 female) (BMNH) (det. D. cavus); no host (1 female) (BMNH) (det. D. cavus); Bristol, reared from Ocytata pallipes 18/09/1979, em. June 1980 (2 of 12 females A, 3 males) (BMNH) (det. D. cavus); Bristol, reared from Triarthria setipennis, leg. 11/10/1979, em. June 1980 (A, 7 females) (BMNH) (det. D. cavus); Bristol, reared from Triarthria setipennis, leg 12/10/1979, em. June 1980 (A, 6 females) (BMNH) (det. D. cavus); Worcestershire, reared from Phygadeuon pr. vexator on Triarthria setipennis (A, 6 females, 2 males) (BMNH) (det. D. cavus); Hampshire, no host (A, 5 females) (BMNH) (det. D. boarmiae); no host, lectotype of Pteromalus cavus (A, 1 female) (BMNH); no host, paralectotypes of Pteromalus cavus (A, 5 females, 1 male) (BMNH) (det. D. cavus); no host, labeled Pteromalus decendens Walker (6 females, 3 males) (BMNH) (det. D. cavus); no location (but most probably from England), no host, lectotype and paralectotype Pteromalus decedens (1 female, 1 male) (BMNH) (det. D. cavus); Kensington, reared from Orgyia antiqua (A, 7 females, 3 males) (BMNH) (det. D. cavus); London, reared from cocoons of Apanteles solitarius (A, 7 females, 4 males) (BMNH) (det. D. cavus); Cambridge, reared from puparium of Calliphora sp. (A, 7 females, 4 males) (BMNH) (det. D. cavus); Cambridge, reared from puparium of Calliphora sp., different collection date than previous (A, 2 females) (BMNH) (det. D. cavus); Cambridge, reared from puparium of Calliphora sp., different collection date than previous (2 males) (BMNH) (det. D. cavus); London: Osterley Park, reared from Triarthria setipennis, labeled Altson Collection (A, 4 females) (BMNH) (det. D. cavus); Fryer (?), reared from psychid (4 females, 1 male) (BMNH) (det. D. cavus); Norfolk, reared from larva of Tyria jacobeae (7 females) (BMNH) (det. D. cavus); Leeds, reared from tachinid of Acronicta psi (A, 5 females, 3 males) (BMNH) (det. D. cavus); London, no host (1 female) (BMNH) (det. D. cavus); Cheshire: Romiley, reared from Hemerobius subnebulosus (= Wesmaelius subnebulosus) cocoons (A, 5 females) (BMNH) (det. D. cavus); London, reared from pupa of Orgyia antiqua, labeled “on defoliating plane” (1 female) (BMNH) (det. D. cavus); London, reared from Orgyia antiqua larva, labeled “on defoliating planes”, probably same location as previous (A, 14 females, 6 males) (BMNH) (det. D. cavus); Essex, reared from pupae of Apanteles sp. from Leucoma salicis (A, 41 females and males) (BMNH) (det. D. cavus); Cambridge, reared from Galleria mellonella cocoon (A, 1 female) (BMNH) (det. D. cavus); London, reared from Apanteles sp. on larva of Orgyia antiqua (A, 6 females, 6 males) (BMNH) (det. D. cavus); London, reared from Apanteles sp. cocoons on Orgyia antiqua, different from previous (A, 3 females) (BMNH) (det. D. cavus); Cambridge, reared from Galleria mellonella (2 males) (BMNH) (det. D. cavus); Farnham Royal, reared from prob. T. setipennis (host attached, det. R. Peters), bred from nest of blackbird (A, 5 females) (BMNH) (det. Dibrachys sp.); Berkshire, reared from small unidentified Diptera puparium attached to specimen, labeled “reared from Decov nest” (?) (A, 1 female) (BMNH) (det. Dibrachys sp.); Berkshire, no host, reared from nest of wren (A, 2 females) (BMNH) (det. Dibrachys sp.); Hampshire (Hants), reared from Triarthria sp. (A, 7 females, 1 male) (BMNH) (det. Dibrachys sp.); Buckinghamshire (Bucks), reared from pupae of Hofmannophila pseudospretella, Woodroffe material 1961 (A, 15 females, 3 males) (BMNH) (det. Dibrachys sp.); Wiltshire: Malmesbury, reared from puparium of Stenepteryx hirundinis (A, 1 female, 1 male) (BMNH) (det. Dibrachys sp.); Stratford-on-Avon, reared from „? Gelis cocoon ex egg sac of Zygiella x-notata “ (1 male) (BMNH) (det. D. cavus); London, no host, labeled Pteromalus lucilla Walker (1 male) (BMNH) (det. D. cavus); Cambridge, reared from sawfly cocoon in old bird nest (4 males) (BMNH) (det. D. cavus); Cambridge, reared from “brown cocoon” (2 males) (BMNH) (det. D. cavus); Enfield, reared from tachinid ex S. salicis (probably Stilpnotia (= Leucoma) salicis) (2 males) (BMNH) (previously unidentified specimen); Farnham Royal, no host, reared from nest of greenfinch (3 males) (BMNH) (det. Dibrachys sp.); British Islands, reared from unidentified tachinid puparium (3 males) (BMNH) (det. Dibrachys sp.); Berkshire: Shillingford, reared from Digonichaeta spinipennis (= Triarthria setipennis) under bark, labeled by Graham “ perversus? see type ” (1 male) (BMNH) (det. Dibrachys sp.). Eritrea: Asmara, labeled “ex no. 12, epiparasites of Ocinara ficicola (?)” (?, host record unclear; either Ocinara ficicola or epiparasites of Ocinara ficicola are host) (2 of 7 females A) (BMNH) (det. Dibrachys sp.). France: Auxonne, reared from Cotesia glomerata (A, 1 females, 1 male) (BMNH) (det. D. cavus); Lyon, reared from Cotesia glomerata (A, 4 females, 3 males) (BMNH) (det. D. cavus); Lyon, reared from Cotesia glomerata, different collection date than previous with same location and same host species (A, 1 female) (BMNH) (det. D. cavus); Lyon, reared from Cotesia glomerata, different collection date than previous with same location and same host species (1 female) (BMNH) (det. D. cavus); Lyon, reared from Cotesia glomerata, different collection date than previous with same location and same host species (A, 1 female, 1 male) (BMNH) (det. D. cavus); reared from moth in beehive (A, 1 female) (BMNH) (det. D. cavus); reared from moth in beehive, different location than previous (1 male) (BMNH) (det. D. cavus); Vizille, reared from Apanteles liparidis (= Glyptapanteles liparidis) on Lymantria dispar on Populus sp. (A, 3 females, 1 male) (BMNH) (det. D. cavus); Châteauneuf Valais, reared from unidentified tachinid in Archips rosana (2 females, both A) (BMNH) (det. D. cavus); South of France, no host, labeled Pteromalus cavus Walker (3 males) (BMNH) (det. D. cavus). Germany: Schleswig-Holstein: Halstenbek, garden of Langkoppelweg 24, N53.6197 E9.8283 (WGS84), reared from Cotesia glomerata, leg. L. Krogmann 26/04/2006, same data as neotype (2 females, both A (ZMH 01–02), 2 males; 2 females in 96 % EtOH) (ZMH); Hamburg-Bramfeld, Umweltzentrum Karlshöhe, reared from Triarthria setipennis, leg. Peters 22/09/2004 (A, 1 female, 1 male) (ZMH); Hessen: Bad Arolsen, reared from Triarthria setipennis, leg. K. Staiber March 2005 (A, 1 female, 2 males in EtOH) (ZMH); Stock HBM laboratory rearing on Galleria mellonella (A, 2 females, 1 male) (ZMH); Stock HBM laboratory rearing on Calliphora vomitoria (numerous females (26 A) and males, including specimens in Figs 7–9) (ZMH); Berlin, reared from Protocalliphora sp. from tit nest (A, 1 female) (BMNH) (det. D. cavus); Kitzeberg, reared from Pieris sp. (2 of 7 females A, 2 males) (BMNH) (det. D. cavus); Rheinhessen, reared as hyperparasitoid (?) from Aporia crataegi (A, 1 female, 3 males) (BMNH) (det. D. cavus); Berlin, reared from Acronycta aceris (A, 1 female) (BMNH) (det. D. boarmiae); Berlin, reared from Euproctis chrysorrhoea (1 male) (BMNH) (det. D. boarmiae); Wangerooge (1 female) (ZMH) (det. D. boarmiae); F.S. Elbe I, leg. 14/08/65 (1 prob. female) (ZMH) (det. D. boarmiae); Bavaria: Oberwaiz, leg. 15/07/ 1983, reared from calliphorid puparium (12 females and males, some in bad condition) (ZMH) (det. D. boarmiae); Schleswig-Holstein: Nützen, leg. 01/12/2002, reared from Triarthria setipennis in nest of Passer montanus, Voucher specimen Dissertation Lars Krogmann 2005, morphological voucher CH _0044 Krogmann & Vilhelmsen 2006 (1 female) (ZMH) (det. D. cavus, Krogmann 2003). Hungary: Hortobágy, Ujszentmargita védett erdó, holotype of Tritneptis elegans (A, 1 female) (HNHM). India: Stinagar, reared from Lymantria obfuscata pupa (A, 5 females) (BMNH) (det. D. cavus). Iran: Gilan, reared from Galleria mellonella (A, 3 females, 1 male) (BMNH) (det. D. boarmiae); Kerman, reared from Kermania pistaciella (A, 1 female) (BMNH) (det. D.? cavus). Italy: Aosta, no host (A, 1 female) (BMNH) (det. D. cavus). Morocco: Middle Atlas, reared from larva (?) of Thaumetopoea pityocampa on Cedrus atlantica (1 female) (BMNH) (det. D. boarmiae). Moldova: Kishinev, reared from Orgyia sp. (3 males) (BMNH) (det. D. cavus). New Zealand: Lincoln, reared from cultured Vespula germanica (A, 2 females, 6 males) (BMNH) (det. D. boarmiae); Christchurch, reared from Vespula germanica (in part cultured) (A, 14 females) (BMNH) (det. D. boarmiae). Pakistan: Mongora, reared from codling moth on apple (prob. Cydia pomonella) (A, 1 female) (BMNH) (det. D.? cavus by Bouček); Baluchistan (no further location labeled, Baluchistan maybe belonging to Iran), reared from pupa of Cacoecia sp. (A, 2 females) (BMNH) (det. D. boarmiae); Quetta, reared from codling moth on apple (A, 6 females, 1 male) (BMNH) (det. D.? boarmiae by Bouček); Mingora C.I.B.C., no host, reared from galls on twigs of P. n i g r a (could be Pinus nigra or Populus nigra) (A, 1 female, 1 male) (BMNH) (det. Dibrachys sp.). Portugal: Central Coast, reared from Pempelia genistella (A, 2 females) (BMNH) (det. D. boarmiae). Serbia: Beograd, no host (A, 1 female) (BMNH) (det. D. cavus); Belgrad, no host (2 females, 1 male) (BMNH) (det. D. cavus). Switzerland: Saxon, reared from Grapholita funebrana (A, 2 females, 2 males) (BMNH) (det. D. cavus); no host (1 female) (BMNH) (det. D. cavus); Nyon, reared from Lobesia botrana (A, 1 female) (BMNH) (det. D. cavus); Simplon, reared from Phytodietus grisianae (A, 2 females, 1 male) (BMNH) (det. D. cavus); Nyon, reared from Grapholita funebrana (1 male) (BMNH) (det. D. cavus); Vaud Commugny, no host, from bird nest (A, 1 female) (NMBE) (det. D. cavus). Syria: Damaskus, reared from Galleria mellonella (A, 2 females, 1 male) (BMNH) (det. D. cavus). Tunesia: Chaffar, reared from Lepidoptera pupa on olive (A, 1 female, 2 males) (BMNH) (previously unidentified specimens). Turkey: Tekirdag, reared from Tenebroides mauritanicus (A, 2 females) (BMNH) (det. D. cavus); Ankara, reared from Galleria mellonella (A, 9 females, 3 males) (BMNH) (det. D. boarmiae); Erzurun, no host, leg. Doganlar 25/06/1981 (1 female) (MDC) (det. D. boarmiae); Erzurun, labeled “ Apis mellifera ” (?, unclear if reared from A. mellifera or from A. mellifera beehive), leg. 18/05/1981 (1 male) (MDC) (det. D. boarmiae); Erzurun, no host, leg. H. Özrek (?) 29/08/1979 (1 female) (MDC) (det. D. cavus); Erzurun, labeled “Prunus mahalep”, leg. Doganlar 13/07/1982 (1 female) (MDC) (det. D. cavus); Ankara, no host, leg. 15/08/1977 Kiliger (?) (2 females) (MDC) (det. D. boarmiae). USA: Ohio: Columbus, syntype of Arthrolytus apatelae (1 female) (USNM); West Virginia: Morgantown, syntype of Arthrolytus pimplae (1 female) (USNM). No location: B. Cooke Coll. 84-52 (1 female) (BMNH) (det. D. cavus); labeled “aus Plettenberg Zucht 1972, H. Wolf“ (6 females, 3 males) (BMNH) (det. D. cavus); reared from nest of Dolichovespula norvegica, leg. C. Nicholson, 1915 (A, 1 female) (BMNH) (det. D. cavus); reared from dipterous puparium under bark, labeled H.W. Miles collection, 1924 (2 females) (BMNH) (det. D. cavus); reared from puparium of Calliphora sp. (2 females, 1 male) (BMNH) (det. D. cavus); lectotype of Pteromalus boarmiae (A, 1 female) (BMNH); paralectotypes of Pteromalus boarmiae Walker (2 females) (BMNH) (det. D. cavus [?]); labeled “leg. Bock 1977” (1 female, 2 males) (ZMH) (det. D. boarmiae); lectotype of Eupelmus cereanus (A, 1 female) (MZUF); paralectotypes of Eupelmus cereanus (2 females, 5 males) (MZUF); syntypes of Cleonymus clisiocampae, labeled “Fitch’s Type ”, “ Semiotellus clisiocampae ” (A, 1 female, 1 male) (USNM); syntypes of Cheiropachus nigrocyaneus (2 females) (USNM); syntype of Pteromalus chionobae (1 female) (USNM); lectotype of Pteromalus gelechiae (1 male) (INHS); paralectotype of Pteromalus gelechiae, labeled “lectoallotype” (A, 1 female), additional paralectotypes of P. g e l e c h i a e (4 females, 4 males) (INHS); labeled “Collectio Ratzeburg [print]”, “Pt. Zelleri Psyche ...[illegible; Ratzeburg's hand?]”, “ Zelleri R. [hand] det. Ratzeburg [print]”, “ Zelleri R. [hand]” (1 male) (NMW) (det. Pteromalus zelleri).
Biology. The long host lists of D. cavus and D. boarmiae in such publications as Peck (1963), Krombein et al. (1979) and Noyes (2003) that summarize previously published records are unreliable for delimiting the true host range of D. microgastri for two reasons: (1) the parasitoid and host identifications have not been verified, and (2) earlier authors did not differentiate between D. microgastri and D. lignicola. Table 9 lists 38 verified host species based on label data of specimens we examined where the host species was identified or could be considered a distinct species (e.g., the listed tachinids). Based on this, D. microgastri is a polyphagous species that uses hosts from at least five insect orders, Diptera (3 families of Cyclorrhapha), Lepidoptera (10 families), Hymenoptera (5 families of “ Symphyta ” and Apocrita), Neuroptera and Coleoptera (one record each). Our list is more reliable, but is still extraordinarily long, which shows D. microgastri can parasitize hosts from various orders and is truly polyphagous.
Tenebroides mauritanicus (Linnaeus) Coleoptera: Trogossitidae Calliphora sp. Diptera: Calliphoridae
Protocalliphora sp. Diptera: Calliphoridae
Stenepteryx hirundinis (Linnaeus) Diptera: Hippoboscidae Ocytata pallipes (Fallén) Diptera: Tachinidae
Triarthria setipennis Diptera: Tachinidae
unidentified tachinid from Acronicta psi (Linnaeus) Diptera: Tachinidae
unidentified tachinid from Archips rosana (Linnaeus) Diptera: Tachinidae
unidentified tachinid from Cydia pomonella (Linnaeus) Diptera: Tachinidae
Apanteles longicauda (Wesmael) Hymenoptera: Braconidae Apanteles solitarius (Ratzeburg) Hymenoptera: Braconidae Cotesia glomerata (Linnaeus) Hymenoptera: Braconidae Glyptapanteles liparidis (Bouché) Hymenoptera: Braconidae Cephus sp. Hymenoptera: Cephidae Gilpinia hercyniae (Hartig) Hymenoptera: Diprionidae Gregopimpla inquisitor (Scopoli) Hymenoptera: Ichneumonidae Phygadeuon sp. Hymenoptera: Ichneumonidae Phytodietus griseanae (Kerrich) Hymenoptera: Ichneumonidae Vespula germanica (Fabricius) Hymenoptera: Vespidae Tyria jacobaeae (Linnaeus) * Lepidoptera: Arctiidae Eutromula pariana (Clerck) Lepidoptera: Choreutidae Coleophora sp. Lepidoptera: Coleophoridae Pectinophora gossypiella (Saunders) Lepidoptera: Gelechiidae Euproctis chrysorrhoea (Linnaeus) Lepidoptera: Lymantriidae Lymantria obfuscata Walker Lepidoptera: Lymantriidae Orgyia antiqua (Linnaeus) Lepidoptera: Lymantriidae Acronicta aceris (Linnaeus) Lepidoptera: Noctuidae Oeneis semidea Say Lepidoptera: Nymphalidae Hofmannophila pseudospretella (Stainton) Lepidoptera: Oecophoridae Pieris sp. Lepidoptera: Pieridae
Galleria mellonella Lepidoptera: Pyralidae Pempelia genistella (Duponchel) Lepidoptera: Pyralidae Thaumetopoea pityocampa (Denis & Schiffermüller) * Lepidoptera: Thaumetopoeidae Kermania pistaciella Amsel Lepidoptera: Tineidae
Cacoecia sp. Lepidoptera: Tortricidae Cydia pomonella (Linnaeus) Lepidoptera: Tortricidae Grapholita funebrana (Treitschke) Lepidoptera: Tortricidae Grapholita molesta (Busck) Lepidoptera: Tortricidae Lobesia botrana (Denis & Schiffermüller) Lepidoptera: Tortricidae Wesmaelius subnebulosus (Stephens) Neuroptera: Hemerobiidae
Only pupal stages of hosts appear to be used by D. microgastri, which implies they are restricted to holometabolous insects. Gontarski (1939) reported the use of cocooned Lepidoptera larvae, which are immobile, but this record is doubtful. Some museum material of D. microgastri was labeled with host records from Lepidoptera larvae, including Tyria jacobaeae (Arctiidae) and Thaumetopoea pityocampa (Thaumetopoeidae). These records are probably wrong or based on unrecognized hyperparasitism of Ichneumonoidea pupae on the lepidopteran larvae and therefore are marked as doubtful in the host list (Table 9).
D. microgastri is a facultative hyperparasitoid through parasitic Hymenoptera and Diptera. Facultative secondary hyperparasitism is common in ectoparasitic parasitoids (Askew & Shaw 1986). The record of parasitism of an Ichneumonidae pupa inside the puparium of the tachinid T. setipennis also demonstrates facultative tertiary parasitism for D. microgastri. Gordh (1981) stated that tertiary parasitism is always facultative.
Polyphagy of D. microgastri is also supported by our laboratory rearings on different species of Calliphoridae (Diptera) and on Galleria mellonella (Lepidoptera: Pyralidae), using parasitoids from a stock originally reared from tachinid puparia (Peters 2007). Although successful rearing in the lab can give information about a parasitoid’s potential ability to use a host, this has to be considered with caution because it is known that parasitoids can use hosts that are normally outside their host range if no natural hosts are available and an artificial situation is created in a Petri dish (Godfray 1994). Accordingly, we only listed field host records in Table 9.
Distribution. Dibrachys microgastri is a cosmopolitan species. Noyes (2003) listed 57 countries for distribution. Those countries we confirmed or added through our examination of specimens are listed in Table 10.
geographic region country geographic region country
Europe Bulgaria Asia Afghanistan Croatia Cyprus Czech Republic India France Iran Germany Pakistan Hungary Syria Italy Africa Algeria Moldova Egypt Portugal Eritrea Serbia Morocco Switzerland Tunesia
Europe: Brit. Isles England North America Canada
Europa/Asia Turkey USA Australia
New Zealand
Taxonomic remarks. After morphological examination of females and males, morphometric analysis, and examination of name-bearing types, we consider D. cavus, D. boarmiae and D. clisiocampae to be synonyms. Dibrachys cavus and D. boarmiae have always been considered close (Graham 1969, Sharkov 1982) and their synonymy was said to be likely but was not formally stated by Zerova et al. (1986). Dibrachys clisiocampae was synonymized with D. cavus by Gahan (1938) but was re-established by Doganlar (1987).
Our analyses show the characters used to separate these three putative species are not reliable, including the three characters of the hypopygium used by Doganlar (1987) (Table 8). The other characters mentioned by Doganlar (1987) and Graham (1969) to separate D. cavus and D. boarmiae also proved to be intraspecifically variable. These characters were: “head breadth to length”, “eye height to breadth”, “eye margin emarginate or not” and the expression of the male gastral spot. Further characters such as the weakly colored discal cloud on the forewing in D. boarmiae was not observed in any specimen, and the shape of the wing stigma and differences in color are considered unsuitable for making taxonomic inferences (see Discussion).
We consider the senior synonym of D. cavus, D. boarmiae and D. clisiocampae to be Dibrachys microgastri (Bouché, 1834), which was originally described as Diplolepis microgastri but assigned to Dibrachys and listed as a possible synonym of D. cavus by Graham (1969). Vidal (2001) and Noyes (2003) listed the name as valid because Graham (1969) did not formally synonymize it. The original description includes a host record from Cotesia glomerata (= Apanteles glomeratus, Microgaster glomeratus) (Hymenoptera: Braconidae). Cotesia glomerata and other braconid species are commonly recorded host species for D. cavus (Noyes 2003; see also examined material and Table 9). Known hosts of D. verovesparum do not include Braconidae and although there is a single record of an Apanteles Förster (Braconidae) parasitoid of D. lignicola (see below), these species cannot be what Bouché (1834) described as D. microgastri because the original description states that the male is “stahlblau angelaufen” (tarnished steel-blue) which does not apply to either D. verovesparum or D. lignicola. The type material of D. microgastri is presumed lost (Graham 1969) and in order to resolve present nomenclatural instability we designate a neotype female for D. microgastri. The neotype was selected from the same host species, Cotesia glomerata, and the same geographic region, Northern Germany, as the type material used by Bouché (1834) in establishing Diplolepis microgastri. Although the name D. cavus has been widely used for almost a century, we deliberately refrain from requesting the International Commission on Zoological Nomenclature to set aside the lesser known name D. microgastri because D. cavus has often been confused with different species of Dibrachys, most notably D. lignicola and D. braconidis, and D. cavus as used in the literature has a highly ambiguous meaning. The adoption of D. microgastri thus underpins the changes associated with our redefinition of the species.
Dibrachys elegans is another new synonym of D. microgastri. The description of Tritneptis elegans by Szelényi (1981) contains a number of mistakes and ambiguous statements, which cause confusion or do not correspond to the holotype or the genus Dibrachys (e.g., funicle is used for flagellum, and “without any sign of notaulices”, “scutellum a little shorter than mesoscutum (1.0:1.9)”, and “ovipositor as long as a third of hind tibia” are stated). However, other parts of the description clearly show that this refers to the specimen that was examined by us as the holotype female. From our morphological examination and morphometric analysis there is no doubt that it is a female of D. microgastri.
In addition to the above synonymy, we confirmed all recorded synonyms of D. cavus and D. clisiocampae as synonyms of D. microgastri after examination of accessible type material. In the following we provide further information on these synonyms.
The type material of all of Ratzeburg’s taxa unfortunately is presumed lost. We examined a male (NMW) labeled “Collectio Ratzeburg” and “Pt. Zelleri Psyche ...” [illegible]. The latter is possibly written in Ratzeburg’s hand. Pteromalus zelleri Ratzeburg, 1848 was described based on a female reared from Bombyx neustria (Linnaeus) (= Malacosoma neustria) (Lepidoptera: Lasiocampidae). We therefore conclude that this male reared from Psyche sp. is not a type specimen of D. zelleri, though it probably is from Ratzeburg’s collection.
Despite the remarks of Novitzky in Graham (1969: 810), we follow the conclusions of Kurdjumov (1913) who stated that D. vesparum (Ratzeburg, 1852) is a synonym of D. boucheanus and hence a synonym of D. microgastri. Kurdjumov (1913) reported that he examined the then still existing type material of Ratzeburg. Graham (1969: 810) mentioned some specimens he received from Z. Bouček that were reared from Dolichovespula saxonica (Fabricius) (Hymenoptera: Vespidae) and that he suspected might be “the true vesparum ”. We include these specimens in the type material of our new species D. verovesparum and do not consider they are conspecific with D. vesparum because the original description of the latter states: (1) gaster as long as head and mesosoma, and (2) body “ölgrün” (oilgreen). A black body without green metallic coloration and a short gaster (always shorter than head plus mesosoma) are two diagnostic characters of our new species and we thus consider D. vesparum as a synonym of D. microgastri. Vespidae are not only hosts of our new species, but are also within the confirmed host range of D. microgastri (Table 9), which supports our conclusion.
The original description of Cheiropachus nigrocyaneus Norton, 1869 states “ 3 specimens bred”. The examined 2 specimens are in bad condition (e.g., heads missing), which makes species assignment difficult though they clearly belong to Dibrachys. Because this name was already synonymized with D. clisiocampae by Girault (1916b: 408) and with D. cavus by Gahan (1938: 211) we consider it a synonym of D. microgastri.
We examined the lectotype male and paralectotypes (one female labeled “lectoallotype” and 4 females and 4 males labeled paratypes) of Pteromalus gelechiae Webster, 1883. There is no doubt about the synonymic status of this species.
The original description of Pteromalus chionobae Howard, 1889 states that it was based on 2 specimens reared from Oeneis semidea (Lepidoptera: Nymphalidae). The single examined female syntype is in bad condition (without head and gaster separated), but it can be assigned to D. microgastri with high certainty.
We examined a syntype of Arthrolytus apatelae Ashmead, 1893 that again is in very bad condition (head, gaster and forewings missing). From our examination of the remaining mesosoma it can be assigned to Dibrachys, but not to species. However, we consider A. apatelae a synonym of D. microgastri based on Girault (1916a; 1916b) and Gahan (1938).
One female syntype of Arthrolytus pimplae Ashmead, 1894 was examined. It was reared from Pimpla inquisitor (= Gregopimpla inquisitor) (Ichneumonidae) and we base this host record for D. microgastri on this specimen.
In addition to the above synonymy, Graham (1956) transferred Pteromalus perversus Walker, 1835 to Dibrachys and subsequently listed it as a questionable synonym of D. cavus (Graham 1969) based on one male from the Walker collection that he considered was the type (probably holotype). Walker (1835) had erroneously described this male as a female in the original description. Unfortunately, we were unable to locate this specimen in the BMNH or elsewhere (e.g., HDOU). We did examine a male labeled “ perversus? see type ” by Graham (BMNH), which Graham (1969: 811) stated was “extremely close” to the probable holotype of D. perversus. This is a male of D. microgastri and suggests that the missing holotype male of D. perversus was also a specimen of D. microgastri. However, the original description by Walker (1835) does not provide any useful information further to the brief notes given by Graham (1969). Graham (1969) did not formally synonymize D. perversus with D. cavus and because we could not locate the probable male holotype of D. perversus we prefer to treat the name as valid, but as a nomen dubium in our list of valid species (see Appendix).
description: Published as part of Peters, Ralph S. & Baur, Hannes, 2011, A revision of the Dibrachys cavus species complex (Hymenoptera: Chalcidoidea: Pteromalidae), pp. 1-30 in Zootaxa 2937 on pages 13-24, DOI: 10.5281/zenodo.202096