The Wharton Lab

Opius stecki Wharton, 2013 ZooKeys 349: 16-19, 61-63.

One of the specimens was sacrificed for sequencing; the morphological description is based on the two remaining specimens, which differed in several features. The paratype has weak sculpture on the propodeum posteriorly, unlike the holotype, though the propodeum is still largely polished and unsculptured. Fore wing 2CUb arises more anteriorly on the distal margin of the 1st subdiscal cell in the holotype than in the paratype, though distinctly above the middle in both.

Holotype: Female, deposited in FSCA (Gainesville, Florida).

Opius stecki belongs to the Opius pipitae species group. The species in this group are similar to members of the baderae and godfrayi species groups in general appearance, reduced propodeal sculpture, absence of a midpit on the mesoscutum, absence of sculpture within the precoxal sulcus, and the notably anterior position of 2CUb along the distal margin of the 1st subdiscal cell. As in members of the godfrayi species group, the labrum is exposed in the gap between the ventral margin of the clypeus and the dorsal margin of the mandibles when the latter are closed. Unlike members of the godfrayi species group, however, the occipital and hypostomal carinae are widely separated ventrally, a characteristic of members of the baderae species group and most of the other species of Opius s.l.

Three species are included in the Opius pipitae species group: O. pipitae, O. stecki, and O. townesi. These species will key to either Pendopius or Opiothorax in the subgeneric classification of Fischer (1972, 1977) and to Adontopius Fischer in Fischer (1999). In Li et al. (2013), they key to Phaedrotoma. In members of the pipitae species group, the vertical carina on the pronotum laterally is very well developed and the pleural sulcus is distinct both anterior and posterior to the propodeal spiracle.

Opiua stecki is much darker in color than O. pipitae. The head is completely dark above while the mesoscutum is extensively pale in O. pipitae and is completely dark in O. stecki. The ovipositor is also slightly shorter in O. stecki and the mandibles not quite as deflected ventrally.

Habitus (Fig. 1). Eyes in dorsal view (Fig. 2) very slightly bulging beyond temples, temples very weakly receding. Clypeus (Figs 4-5) 1.9–2.1 x wider than high, very weakly punctate throughout; weakly triangular in outline; weakly bulging, nearly flat in profile, slightly protruding ventrally; ventral margin weakly concave in anterior view with dorsal margin of mandibles nearly straight, very weakly deflected, narrowly exposing part of labrum; base of mandible (Fig. 5) slightly extended ventrally, though not developed as a discrete basal tooth, malar space thus a little shorter relative to basal width of mandible compared to O. pipitae. Malar sulcus present, weak. Antenna broken in all specimens. Mesosoma (Figs 3, 6-8) 1.45–1.55 x longer than high. Pronotum laterally (Fig. 3) with vertical groove finely sculptured dorsally and ventrally, weakly wrinkled to smooth medially posteriorad distinct vertical carina, carina weaker, evanescent dorsally and ventrally. Notaulus (Figs 2, 6) a short groove weakening posteriorly, not as discrete posteriorly nor as long as in O. pipitae, widely separated from anterior margin, not margined anteriorly by carinae. Propodeum (Figs 6, 8) largely smooth, polished, with weak, irregular sculpturing over posterior 0.4 in one paratype. Fore wing (Fgis 7, 9) 3RSa 1.4 x longer than 2RS; (RS+M)a very weakly sinuate. T1 (Figs 7-8) 1.9–2.0 x wider at apex than at base, length 0.9–1.1 x apical width; smooth, unsculptured basally and laterally, very weakly rugulose, nearly smooth (paratype) to strigose over apical 0.6–0.7 (holotype); dorsal carina distinct, elevated basally, converging, extending almost to spiracle in paratype, stronger, distinct over basal 0.7–0.8 in holotype. Ovipositor (total length) approximately 1.2 x longer than mesosoma (Fig. 9). Color (Figs 1, 4, 5): Head almost entirely black; clypeus varying from mostly black with ventral 0.3–0.4 yellow-orange to largely yellow-orange with small black spot mid-dorsally; base of mandible yellow, narrow band on malar space between clypeus and mandible whitish yellow; palps and remaining mouthparts white. Mesosoma entirely black. Metasoma black, T3–T6 with brownish posterior margins. Legs mostly yellow, nearly white basal-ventrally, tarsi dark brown, except fore basitarsis yellow, hind tibia dark brown over basal 0.15, brown over apical 0.4 fading to yellow medially. Body length 2.7–3.3 mm; wing length 3.8 mm; mesosoma length 1.15–1.4 mm.

Type locality: Guatemala, Deptartamento Zacapa, Sierra de las Minas.

The type series was reared from stem galls made by an apparently undescribed species of Polionota (Tephritidae) on the asteracean Coreopsis mutica DC.

Holotype labels:

GUATEMALA: Dept. Zacapa second line: Sierra de las Minas, San Lorenzo rd; third line: 1600–1700m; vic 15.07329, -89.68463; fourth line: 21–24 V 2010; Sutton, Steck, Skelley, fifth line: Monzon S.; oak forest

Second label:
reared from galls Polionota n. sp.
(Diptera: Tephritidae) ex Coreopsis
mutica DC. (Compositae)
emerged late VI–VII 2010

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. Gary Steck kindly made all of the material of this species 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.