Pteromalus bedeguaris ( Thomson, 1878 )

Gómez, Jose F. & Nieves-Aldrey, Jose Luis, 2012, Notes on the larval morphology of Pteromalidae (Hymenoptera: Chalcidoidea) species parasitoids of gall wasps (Hymenoptera: Cynipidae) in Europe, Zootaxa 3189, pp. 39-55 : 51-52

Pteromalus bedeguaris ( Thomson, 1878)

Measurements. Body length: 1.1–3.2 (2.1) mm, maximum width: 0.53–1.2 (0.7) mm (n=48) ex gall Diplolepis mayri (Schlechtendal) ; body length: 0.75–3.3 (1.8) mm, maximum width: 0.6–0.8 (0.65) mm (n=3) ex gall Diplolepis rosae (Linnaeus) ; body length: 1.4–1.55 (1.45) mm, maximum width: 0.6 mm ex gall Diplolepis spinosissimae (Giraud) (n=2).

Description. Whitish or yellowish; integument mostly smooth on all body segments, except first thoracic which appears striated-rugose and with a row of very short spiniform setae ( Figs 4 D, 5D, 6D); body 2× as long as broad, broadest at thoracic segments, tapering gradually posteriorly ( Fig. 4 D); anal segment truncated, broader than long; body ventrally curved in lateral view ( Fig. 5 D); ventral margins of body segments straight.

Head (anterior view) ( Fig. 6 D) rounded, 1.1× as broad as high; upper margin of vertex also rounded; medial area of vertex slightly incised; head setae very short and indistinct; antero-medial setae of antennal area slightly above antennae; clypeal setae very short; antennae button-like; ventral margin of clypeus curved; labrum trapezoid, 4× as long as wide ( Figs 6 D, 7D).

Mouth parts ( Fig. 7 D). Maxillae differentiated from labium; two pairs of maxillary palps visible with two pairs of very short setae; labium semicircular, convex and not collapsed, with a pair of inconspicuous setae.

Mandibles ( Fig. 8 C). Tooth 1.8× longer than wide measured at its base; apex sharp, very thin and slender; angle separating inner side of tooth and base of mandible obtuse (>90º) with outer margin of tooth almost straight but with a broad, basal emargination.

Biology. Nordlander (1973) provided a detailed description of the terminal larva of the species. This species ( Fig. 9 I) parasitizes primarily Diplolepis larvae on which it is a common ectoparasitoid and it has been reported also as a facultative hyperparasitoid of Glyphomerus stigma (Fabricius) (Torymidae) ( Redfern & Askew 1992, Gómez et al. 2008). Another inhabitant of Diplolepis galls is Orthopelma mediator (Thunburg) (Ichneumonidae) which may also act as a secondary hyperparasitoid of P. bedeguaris . With Caenacis inflexa (Ratzeburg) (not included in this study), it is the only species of pteromalid reared from galls of Diplolepis on rose shrubs ( Fig. 9 H).

Material examined. ex gall D. mayri on Rosa sp., Spain, Guadalajara: Retiendas (n=44) J. L. Nieves leg.; Soria: Cabrejas del Pinar (n=2), Embalse de la Cuerda del Pozo: (n=2). ex gall D. Rosae on Rosa sp., Spain, Leon: Valporquero (n=1); Madrid: Casa Eulogio (n=2) J. L. Nieves leg. ex gall D. Spinosissimae on Rosa sp., France, Pyrénées Atlantiques: Vallée D’Ossau (n=2) J. L. Nieves leg.

Figures

FIGURE 4. Ventral view of terminal instar pteromalid larvae (A = agamic generation; S = sexual generation for host). A. Arthrolytus glandium ex Callirhytis rufescens (A). B. Cecidostiba fungosa ex Andricus quercusradicis (S). C. Cecidostiba geganius ex Andricus quercusradicis (A). – D. Pteromalus bedeguaris ex Diplolepis rosae. E. Pteromalus hieracii ex Aulacidea follioti. F. Pteromalus isarchus ex Xestophanes potentillae. G. Rivasia fumariae ex Neaylax versicolor. H. Stinoplus lapsanae ex Timaspis lapsanae.

FIGURE 5. Lateral view of terminal instar pteromalid larvae (A = agamic generation; S = sexual generation for host). A. Arthrolytus glandium ex Callirhytis rufescens (A). B. Cecidostiba fungosa ex Andricus quercusradicis (S). C. Cecidostiba geganius ex Andricus quercusradicis (A). D. Pteromalus bedeguaris ex Diplolepis rosae. E. Pteromalus hieracii ex Aulacidea follioti. F. Pteromalus isarchus ex Xestophanes potentillae. G. Rivasia fumariae ex Neaylax versicolor. H. Stinoplus lapsanae ex Timaspis lapsanae.

FIGURE 6. Anterior view of the head of terminal instar pteromalid larvae (A = agamic generation; S = sexual generation for host). A. Arthrolytus glandium ex Callirhytis rufescens (A). B. Cecidostiba fungosa ex Andricus quercusradicis (S). C. Cecidostiba geganius ex Andricus quercusradicis (A). D. Pteromalus bedeguaris ex Diplolepis rosae. E. Pteromalus hieracii ex Aulacidea follioti. F. Pteromalus isarchus ex Xestophanes potentillae. G. Rivasia fumariae ex Neaylax versicolor. H. Stinoplus lapsanae ex Timaspis lapsanae.

FIGURE 7. Anterior view of mouthparts of terminal instar pteromalid larvae (A = agamic generation; S = sexual generation for host). A. Arthrolytus glandium ex Callirhytis rufescens (A). B. Cecidostiba fungosa ex Andricus quercusradicis (S). C. Cecidostiba geganius ex Andricus quercusradicis (A). D. Pteromalus bedeguaris ex Diplolepis rosae. E. Pteromalus hieracii ex Aulacidea follioti. F. Pteromalus isarchus ex Xestophanes potentillae. G. Rivasia fumariae ex Neaylax versicolor. H. Stinoplus lapsanae ex Timaspis lapsanae.

FIGURE 8. Anterior view of left mandible of terminal-instar pteromalid larvae (A = agamic generation for host). A. Arthrolytus glandium ex Callirhytis rufescens (A). B. Cecidostiba geganius ex Andricus quercusradicis (A). C. Pteromalus bedeguaris ex Diplolepis rosae; and anterior view of the left mandible. D. Stinoplus lapsanae ex Timaspis lapsanae. E. Rivasia fumariae ex Neaylax versicolor.

FIGURE 9. A. Larval cell of of Callirhytis rufescens (Agamic generation) with terminal-instar larvae of Arthrolytus glandium. B. Galls of Aulacidea hieracii on Hieracium spp. C. Galls of Xestophanes potentillae on runners of Potentilla reptans. D. Old galls of Callirhytis glandium (Agamic generation). E. Lateral habitus of Cecidostiba fungosa, adult female. F. Galls of Andricus quercusradicis (Agamic generation) on Quercus pyrenaica. G. Cross-section of unilocular gall of Neaylax versicolor showing fully-grown larva of Rivasia fumariae. H. Fresh galls of Diplolepis rosae on Rosa spp. shrub. I. Lateral habitus of Pteromalus bedeguaris, adult female. J. Galls of Timaspis lapsanae on Lapsana communis. K. Terminal instar larva of Stinoplus lapsanae ex gall of Timaspis lapsanae.