Eurytoma brunniventris Ratzeburg, 1852

Gómez, José Francisco, Nieves-Aldrey, José Luis, Nieves, María Hernández & Stone, Graham Nicholas, 2011, Comparative morphology and biology of terminalinstar larvae of some Eurytoma (Hymenoptera, Eurytomidae) species parasitoids of gall wasps (Hymenoptera, Cynipidae) in western Europe, Zoosystema 33 (3), pp. 287-323 : 304-306

publication ID	https://doi.org/ 10.5252/z2011n3a3
persistent identifier	https://treatment.plazi.org/id/03E487A7-AF5A-276F-07ED-FAE66B4AFABF
treatment provided by	Felipe
scientific name	Eurytoma brunniventris Ratzeburg, 1852
status

Treatment

Eurytoma brunniventris Ratzeburg, 1852 View in CoL

MATERIAL EXAMINED. — Ex Andricus coriarius : Spain. Cádiz, La Suara-Jérez, 16.X.2004, J. L. Nieves leg (n = 1)

Ex Cynips quercus : Spain. Madrid, Dehesa de Arganda, 24.X.2004, J. L. Nieves leg (n = 1).

Ex Plagiotrochus panteli : Spain. Madrid, Dehesa de Arganda, 6.VI.2004, J. L. Nieves leg (n = 4).

Ex Plagiotrochus australis : Spain. Madrid, Dehesa de Navacerrada, 27.VI.2002, J. L. Nieves leg (n = 1).

Ex Andricus hispanicus : Spain. Madrid, El Escorial, 2.VIII.2003, J. L. Nieves leg (n = 1).

Ex Andricus kollari : Spain. Madrid, El Escorial, 2.VII.2003, J. L. Nieves leg (n =1, MNHN-EY6410).

Ex Cynips quercus : Spain. Madrid, El Escorial, 2.VIII.2003, J. L. Nieves leg (n = 4).

Ex Plagiotrochus australis : Spain. Madrid, El Pardo, 13.III.2004, J. L. Nieves leg (n = 2).

Ex Trigonaspis synaspis : Spain. Madrid, Miraflores de la Sierra, 3.IX.2005, J. L. Nieves leg, (n = 1).

DESCRIPTION

n = 15; body length 1.87 mm (range 1.3-2.7); body width 1.04 mm (0.5-1.6) ( Figs 5B View FIG ; 7B View FIG ; 14D View FIG ); body barrel-shaped or fusiform, tapering anteriorly and posteriorly: ratio L/W = 1.9; body segments widest in the mid-region; anterodorsal protuberances clearly protruding from second thoracic segment to the eighth abdominal ( Fig. 7B View FIG ). Ratio SA/LAA = 0.45; antero-medial setae of the antennal area situated at the same level as the antennae; ratio SA/DAV = 1.13; antero-medial setae of the vertex relatively high on the upper face much closer to the anterior margin of vertex than to antennae ( Fig. 9B View FIG ); dorsal-labral setae as long as clypeal setae; ventral margin of clypeus indistinct and without any discernible suture; labrum with slight divisions limited to apical part; maxillary palps conspicuous ( Fig. 11B View FIG ).

Mandibles invisible, covered by labrum ( Fig. 11B View FIG ); two teeth in both mandibles ( Figs. 13B View FIG ; 14G View FIG ); ratio L/W 1T = 2; outer margin of the first tooth of mandible strongly convex; tip moderately recurved. Apex of second tooth more or less pointed and straight, directed upwards in the same direction as the first tooth. Inner margin of mandible from the base of second tooth more or less straight and not interrupted ( Fig. 13B View FIG ).

BIOLOGY

An ectoparasitoid species associated with more than 75 different oak cynipid galls across the Palaearctic. Published data ( Ács et al. 2002) and our own unpublished molecular data show this species to represent a complex of several sibling species. The life cycle is multivoltine and larvae attack the gallinducing cynipid larva and inquiline cynipids ( Askew 1961, 1975, 1984; Schönrogge et al. 1995, 1996a, b) ( Fig. 14C View FIG ). Fully-grown larvae overwinter inside the gall and the adults emerge in synchrony with the development of new host galls ( Schönrogge et al. 1996a, b; Fig. 14E View FIG ). As this species frequently supplements its diet by also feeding on gall tissue, plant debris are usually found in larval cells containing E. brunniventris ( Fig. 14F View FIG ); this species is the only polyphagous chalcid in cynipid galls known to eat gall tissue.

REMARKS

The larva of E. brunniventris is quite similar to that of E. robusta . The body shape and relative size of the second mandible tooth separates the two species. Eurytoma brunniventris is the commonest eurytomid species associated with cynipid galls on oaks.