The Wharton Lab

Opius marshi Wharton, 2013 ZooKeys 349: 16-18, 47-49.

The male wasp from P. eminens is larger than the female from S. skutchii and the dark markings on the head are not quite as extensive though of the same pattern (compare figures of male and female above). The base of the ovipositor and ovipositor sheath are too well-concealed in the only female specimen to provide a useful approximation of total length for this species.

Holotype: Female, deposited in UNAM.

Opius marshi belongs to the godfrayi species group based on the fusion of the hypostomal and occipital carinae ventrally (Fig. 6 above). It differs from O. godfrayi by the more broadly exposed labrum (most evident in Fig. 5 above) and from O. nablus by the more deeply incised notauli (best seen in Fig. 4 above).

Unlike most other Opiinae, the occipital and hypostomal carinae meet well above the base of the mandible in members of the godfrayi species group, continuing to the mandible as a single, flange-like ridge. They would thus key to Apodesmia Foerster in Li et al. (2013), though differing notably from the type species of Apodesmia in the absence of a midpit on the mesoscutum and absence of a sculptured precoxal sulcus, among other features. Some members of the godfrayi species group will key to Opius (Pendopius Fischer) in the subgeneric keys of Fischer (1972, 1999), but differ from the type species of Pendopius in lacking a basal tooth or lobe on the mandible. Others will key to Opiothorax Fischer, the type species of which similarly has a basal lobe on the mandible.

While the fusion of the occipital and hypostomal carina ventrally in mambers of the godfrayi species group suggests a relationship to Apodesmia, sculptural characteristics of the mesosoma (especially notauli, pronotum, precoxal sulcus, and propodeum) and metasoma (T1) as well as the position of fore wing 2CUb suggest a closer relationship to members of the baderae species group.

Habitus (Figs 1-2) Eyes in dorsal view (Figs 3-4) bulging beyond temples, temples weakly but distinctly receding. Clypeus (Fig. 7) 1.75–1.85 (male) and 2.0 (female) x wider than high, weakly punctate throughout, more deeply punctate along ventral margin; very weakly triangular, nearly hemispherical with epistomal sulcus almost evenly rounded; nearly flat in profile dorsally, ventral margin weakly but distinctly protruding, truncate in anterior view with mandibles deflected, exposing most of labrum. Antenna with 43–45 (male) and 46 (female) flagellomeres. Malar sulcus (Figs 5-6) impressed throughout, deeper near eye, weak to nearly absent near mandible. Mesosoma (Figs 8-12) 1.35–1.4 x longer than high. Pronotum laterally (Figs 5-6) weakly crenulate dorsally and ventrally along posterior side of distinctly elevated vertical carina, broadly absent medially, sculpture more distinct in largest specimen. Notaulus (Figs 8-9) about as in O. godfrayi , but curved groove not ending in distinct pit at anterior end. Setae scattered along traces of notaulus longer and denser over anterior 0.7 of mesoscutum. Metapleuron with median pit adjacent anterior margin not directly connected to dorsal pit at posterior margin by a sulcus; ventral margin without well-developed spine anteriorly, but with ventral carina angled at 90 degrees anteriorly and weakly expanded as a flange. Propodeum (Figs 10, 12) with small rugulose area mesal-ventrad spiracle, a few irregular, deep punctures anteriorad ends of short lateral-median carinae, and a few weak carinulae along posterior margin, otherwise mostly smooth and polished; sculpture more distinct in largest specimen. Fore wing (Fig 13) with 3RSa 1.55–1.75 x longer than sinuate to strongly sinuate 2RS; (RS+M)a weakly sinuate. T1 (Figs 12, 15) 1.75–2.0 (male) and 2.15 (female) x wider at apex than at base, 0.95–1.0 x as long as apical width; T1 smooth, unsculptured basally and apical-laterally, striate to finely strigose over middle portion of apical 0.4–0.5, more extensively sculptured in female: striate to strigose apical-laterally and over apical 0.5; dorsal carina sharply elevated basally, forming almost a tuberculate angle as it extends posteriorly, extending to apex but broader, rounded, gradually becoming indistinct over apical 0.5. Color (Figs 1-15) : Head adjacent eyes yellow above, fading to whitish below, especially on face laterad clypeus and mouthparts (except apical teeth of mandible dark); frons medially, continuing posteriorly as a band through ocellar field and onto vertex dark brown to black, with similarly dark transverse band across middle of occiput, enlarged at each end; face with infumate spot dorsal-medially or broader dark band extending to epistomal sulcus; head darker in female than male. Mesosoma of male yellow-orange with propodeum, midline of metanotum, and small spot along lateral margin of mesoscutum immediately anteriorad axilla black; small to large spot at apex of scutellum and large spot dorsal-medially on pronotum laterally dark red-brown; parascutellar field, posterior-lateral field of metanotum, and mesopleuron ventrally anteriorad mid coxa infumate (as a spot in one specimen and a longer streak in the other); tegula and basal wing sclerite white, propleuron and polished, anterior margin of pronotum laterally white or nearly so; female darker, with mesopleuron mottled yellow and brown and scutellar and metanotal areas completely suffused with brown. Metasomal terga black with hyaline posterior margin of T3 and following usually visible, T3–T6 medially with white band along anterior margin, visible portion of T7 white in female. Fore and mid tibiae and femora whitish to pale yellow; hind femur with pale brown subapical spot only on anterior face, otherwise pale yellowish white; hind tibia brown with basal 0.2 dark brown, usually pale brown medially, especially on posterior face. Body length 4.0–4.75 mm; wing length 4.75–5.4 mm; mesosoma length 1.65–1.9 mm.

Type locality: Mexico, Chiapas, south slope Volcan Tacaná, Chiquihuites

Opius marshi was reared from tephritid stem galls of Squamopappus skutchii and Podachaenium eminens, both members of the plant family Asteraceae. Sample 93M11 from Squamopappus skutchii produced two wasps and one fly (66.7% parasitism), and sample 93M22 from Podachaenium eminens yielded one fly and one wasp (50% parasitism). Both are new host plant records for E. apicata.

Holotype labels:

MEXICO: Chiapas
Chiquihuites, ~15°05’N
92°06’W, NW Union Juarez

Second label:
S slope Volcan Tacana,
1800–2000 m, 31.X.1993
A.L.Norrbom & C.Estrada

Third label:
reared ex. stem gall
Squamopappus skutchii
(Blake) Janson, Harriman
& Urbatsch (93M11)

Fourth label: reared ex stem
gall of Eutreta apicata
(Tephritidae)

This page was assembled largely by Bob Wharton and Andrew Ly. It is part of a revision of New World, mostly neotropical, opiines reared from non-frugivorous Tephritidae conducted 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 and especially Danielle for preparing the plates. 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.