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Doryctobracon anneae Wharton, 2013 ZooKeys 349: 16, 21-23.

Doryctobracon anneae differs substantially from the species of Doryctobracon known as parasitoids of fruit-infesting Tephritidae by the near absence of notauli. Nevertheless, the wing venation and shape of the head and clypeus clearly place this species within Doryctobracon. Doryctobracon anneae belongs to the D. crawfordi species group characterized by the propodeal sculpture reduced to a pair of median carinae emanating from the posterior margin of the propodeum.

There is variation in the color pattern among the specimens available for study and although they were reared from two different host plants, specimens from Dahlia imperialis exhibited the maximum extent of variation (compare Figs 1 and 15 in the description section). Ten percent of the specimens, representing two males and one female, all reared from Dahlia imperialis, have a dark mesoscutum while all others are completely pale. Two specimens, also from D. imperalis, have the mesosoma ventrally much less extensively dark, with the tegula only partially brown.

Holotype: Female, deposited in UNAM.

This species is easily separated from the species of Opius s.l. that attack non-frugivorous Tephritidae by the short second submarginal cell, with 3RSa much shorter than 2RS (Fig. 1), and from all but O. taramegillae Wharton by the complete absence of an occipital carina (Fig. 2). The virtually absent notaulus separates D. anneae from nearly all other species of Doryctobracon. The notaulus is also relatively poorly developed in D. homosoma (Fischer), but the latter has an orange head and a bright yellow spot around the stigma on the otherwise infumate fore wing.

Species of Doryctobracon most closely resemble those species of Diachasmimorpha Viereck with reduced occipital carinae but differ primarily in the position of fore wing m-cu, the larger tegula, and the elevated posterior margin of the pronotum dorsally. Fischer (1977) and Wharton (1997) provide redescriptions of Doryctobracon. Wharton and Marsh (1978), Fischer (1977), and Wharton and Yoder (2013: Parasitoids of fruit-infesting Tephritidae, www.paroffit.org ).

Eyes in dorsal view not or only slightly bulging beyond temples (Figs 2, 7), temples not receding. Eye in lateral view (Figs 1, 3) 1.55–1.75 (male) and 1.7–1.9 (female) x longer than temple. Malar space large, greater than basal width of mandible, 0.45–0.6 x eye height. Clypeus (Figs 4-6) sinuate, distinctly protruding as a lobe medially on ventral margin. Antenna with 41–47 flagellomeres; first flagellomere 0.8–0.9 x length of second, 1.5–1.75 x longer than wide; second flagellomere 1.75–2.0 x longer than wide. Mesosoma 1.3–1.4 x longer than high, 1.35–1.45 x higher than wide, 1.8–1.9 x longer than wide. Pronotum dorsally (Figs 7-9) a broad, flat plate with weakly crenulate, shallow transverse groove near posterior margin, usually with small dimple-like depression dorsal-medially within groove; pronotum laterally with shallow, sinuate vertical groove, carinately margined on anterior side over dorsal 0.25; roughly elliptical area near middle of posterior-ventral margin delineated by very weakly crenulate groove. Notaulus virtually absent (Figs 7-9), represented primarily by a band of setae extending from anterior-lateral margin of mesoscutum to broad, shallow, median depression at posterior margin. Propodeum (Fig. 12) densely setose and punctate, with a pair of broadly rounded carinae extending anteriorly from median boss at posterior margin, carinae never extending to anterior margin, usually reaching midpoint; pleural carina often absent, sometimes weakly indicated on posterior 0.4–0.5. Metapleuron densely setose and punctate. Fore wing (Figs 10, 11) 2RS 1.3–1.6 x longer than 3RSa. T1 1.05–1.1 (male) and 1.15–1.3 (female) x longer than apical width, apex 1.9–2.3 (male) and 2.25–2.4 (female) x wider than base; T1 (Figs 12, 13) dorsal carinae parallel-sided, usually extending to level of spiracle as distinctly elevated ridges, then gradually weakening, not reaching posterior margin; spiracle posteriorad midpoint. Ovipositor (Fig. 14) 3.1–3.2 x and ovipositor sheath 2.6 x longer than mesosoma; ovipositor without subapical dorsal node. Head black; antenna, legs, ventral 0.6–0.4 of mesosoma, tegula, extreme base of T1 and ovipositor sheath dark brown, palps brown; mesosoma dorsally usually (90%) and metasoma entirely yellow-orange as in Fig. 1. Body length 3.8–6.0 mm; wing length 4.2–6.6 mm; mesosoma length 1.4–2.25 mm, with smallest male considerably smaller than smallest female.

Members of this genus are native to the New World. This particular species was reared from hosts collected in Mexico at two sites in the vicinity of Lago de Zempoala, Morelos and one site 2–4 km north of Angangueo in Michoacan.

Hosts are known for nearly all described species of the genus Doryctobracon, and all are parasitoids of larval Tephritidae, primarily of frugivorous species. All known specimens of D. anneae were reared from puparia of the tephritid Gymnocarena mexicana (Aczél) infesting flower heads of the asteraceans Dahlia imperalis and D. merkii Lehm. Most of the puparia were individually isolated during rearing, giving added confidence to the host records. Host data are detailed in Norrbom (2006: 223).

Data on a few of the labels indicated that at least some of the parasitoids emerged from their hosts one year after the flower heads were collected. Flies in all four samples were heavily attacked by this opiine, with parasitism rates of 85.7, 80.0, 87.5, and 66.7% for four separate collections.

The apex of the ovipositor is narrower in D. anneae relative to species such as D. crawfordi, which may indicate an earlier host stage attacked but may also be a reflection of the differences in host habitat (flower head vs. fruit).

Holotype labels:
MEXICO: Morelos
Lago de Zempoala
23–25.ix.1991
A. L. Norrbom, #57

Second label:
reared ex. capitulae
Dahlia imperialis
Roezl. (91M16)

Third label: reared ex puparium
Gymnocarena mexicana
(Tephritidae)

This page was assembled largely by Bob Wharton. It is part of a revision of New World Opiinae attacking flower-infesting, stem-mining, and stem-galling Tephritidae by Wharton and Norrbom (2013). We are particularly grateful to Danielle Restuccia, Patricia Mullins, Trent Hawkins, Lauren Ward, and Gabriella Vasquez, who did all of the imaging. Danielle and Andrew Ly assisted with the preparation of species pages on the public site. Paul Marsh initially made much of this material available to the senior author. Matt Yoder and Istvan Miko provided guidance on databasing issues associated with our use of mx and HAO respectively. We thank David Wahl (AEIC), Norm Penny and Bob Zuparko (CAS), Andrew Bennett and Henri Goulet (CNC), Max Fischer and Dominique Zimmermann (NHMW), and Paul Marsh and Robert Kula (Systematic Research Laboratory, USDA; USNM) for facilitating loans and general assistance associated with examination of holotypes and other material in their care. This work was supported largely by NSF DEB 0949027, with REU supplement 1313933 (to Wharton) and partly by NSF/PEET DEB 0328922 (also to Wharton). Page last updated January, 2014.

This material is based upon work supported by the National Science Foundation under Grant Numbers DEB 0949027 and DEB 0328922 with REU supplement 1313933.
Any opinions, findings, and conclusions or recommendations expressed in this material are those of the author(s) and do not necessarily reflect the views of the National Science Foundation.