The Wharton Lab

Opius marci Fischer, 1968: 77–78 (key); 87–90 (description). Holotype female in AEIC (examined).
Opius marci: Fischer 1971: 86 (catalog).
Opius (Merotrachys) marci: Fischer 1977: 655–657, 682–683 (key, redescription); Fischer 1979: 264–266 (key); Yu et al. 2005, 2012 (electronic catalogs).

This species is known only from the female holotype.

Exclusion of these two species from the ingenticornis species group is based primarily on the short antennae and the T1 profiles that are concave and gradually sloping anteriorly, and secondarily on the smaller pronope.

Face (Fig. 2) distinctly punctate, punctures separated by 1–2 x their diameter, smooth between punctures. Eye in lateral view (Fig. 3) about 3.8–4.0 x longer than temple; temples in dorsal view receding (Fig. 4). Female antenna with 29 flagellomeres; setae on basal flagellomeres short, thick, dark. Mesoscutum anteriorly with distinct declivity (Fig. 3); notaulus extending laterally towards tegula as groove bordered by distinct supramarginal carina. Propodeum (Figs 6, 7) weakly rugulose to smooth with anterior median trough separated from well-defined, discretely margined, pentagonal areola posteriorly. Fore wing (Fig. 8) with 3RSa weakly curved, 1.5 x longer than 2RS; m-cu postfurcal. T1 evenly curving into basal pit anteriorly (Fig. 6), not distinctly declivitous, pit not delimited posterior-medially; surface rugulose, at least medially; dorsal carinae (Fig. 7) parallel-sided throughout, not sinuate, transversely carinate between dorsal carinae. T2 very faintly shagreened medially, mostly smooth, polished; T3 smooth, polished. Ovipositor long; ovipositor sheath about 1.3–1.4 x longer than mesosoma. Color as in Figs 1, 7: head, body, hind coxa and femur pale orange; antenna with pale subapical ring; wing infumate.

This species is most similar to O. duplocarinatus . Both species have a pale subapical ring on the antenna (Fig. 1) whereas the flagellum is uniformly dark in all members of the ingenticornis species group. The setal pattern on the basal flagellomeres of these two species is also similar, with the setae shorter and not quite as thick as in species such as O. albericus, but thicker and darker than in species such as O. matthaei. Both O. duplocarinatus and O. marci also have a relatively long ovipositor (Fig. 1) and relatively short antenna (with 29–31 flagellomeres). Exclusion of these two species from the ingenticornis species group is based primarily on the short antennae and the T1 profiles that are concave and gradually sloping anteriorly, and secondarily on the smaller pronope. Although_O. duplocarinatus_ and O. marci are nearly identical, they have been placed in different subgenera (Fischer 1977, 1979, 1979) because O. marci has very faintly shagreened sculpture on T2 and T2 sculpture is lacking in O. duplocarinatus . There are also minor differences in the propodeum, with the areola more discrete in O. marci, and O. duplocarinatus has a distinct (though unsculptured) precoxal sulcus.

Additionally, this species shares the following characteristics with members of the ingenticornis species group: Mandible short, broadly triangular, dorsal margin strongly angled ventrally, broadly exposing labrum. Occipital carina broadly absent dorsally, the gap in dorsal view at least as wide as distance between eyes; carina well developed laterally and ventrally, widely separated from hypostomal carina ventrally. Mesoscutum without midpit; notaulus short, curved, pit-like anteriorly, narrowing and evanescent posteriorly. Propodeum with median depression at least anteriorly, never with median longitudinal carina. Mesopleuron without sternaulus; hind margin of mesopleuron not obviously crenulate on dorsal 0.5. Fore wing 2CUb arising from or near middle of first subdiscal cell. Hind wing with RS distinctly infumate; m-cu absent. T1 with dorsal carinae parallel or nearly so, extending from base to apex; laterope large, deep; dorsope absent.

Peru, Loromayo.

Labels attached to the holotype are shown in Fig. 1.

This page was assembled largely by Bob Wharton. It is part of a revision of the Opius ingenticornis species group conducted by Sophia Daniels, Xanthe Shirley, Danielle Restuccia and Bob Wharton. We thank David Wahl (American Entomological Institute, Gainesville, FL) for loans and general assistance associated with examination of holotypes, as well as Max Fischer and Dominique Zimmermann (NHMW), Henri Goulet (CNC) and Paul Marsh (formerly USDA, Washington, D. C.) for facilitating other loans and work with material in their care. Matt Yoder provided guidance on databasing issues associated with our use of mx. This work was conducted at Texas A&M University and was supported in part by NSF DEB 0949027, with REU supplement 1213790. Page last updated February, 2013.

This material is based upon work supported by the National Science Foundation under Grant Number DEB 0949027 and associated REU supplement 1213790.
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.