Opius peleus Fischer

Wharton, Robert & Norrbom, Allen L., 2013, New species and host records of New World, mostly Neotropical, opiine Braconidae (Hymenoptera) reared from flower-infesting, stem-galling, and stem-mining Tephritidae (Diptera), ZooKeys 349, pp. 11-72 : 50-53

Opius peleus Fischer Figs 2, 9, 27, 71-74

Opius peleus Fischer, 1970: 802-804. Holotype male in AEIC (examined).

Opius peleus : Marsh 1974: 287 (synonymy); Marsh 1979: 210 (catalog).

Opius (Merotrachys) peleus : Fischer 1977: 655, 695-697 (key, redescription); Fischer 1979: 264 (key); Yu et al. 2005, 2012 (electronic catalogs).

Opius telephosi Fischer, 1970: 812-815. Synonymized by Marsh (1974: 287).

Type locality.

USA, South Carolina, Pickens County, Wattacoo.

Type material.

Holotype. Male (AEIC), data label, first line: Wattacoo, Pickens Co., S. C. second line: V. 27. 61 third line: G. F. Townes.

Other specimens examined.

5 females, 2 males, USA: Tennessee, Blount Co., Great Smoky Mountains National Park, Abrams Creek Campground, 3.xi.2003, G.J. Steck & B.D. Sutton, reared ex. Strauzia intermedia from root mines of Rudbeckia laciniata (FSCA, TAMU); 1 female, same data except 7.viii.2002; 1 female, same data except 5.iii.2004 (FSCA).

Diagnosis.

Temple relatively broad, eye about 1.75-2.1 (female) and 1.35-1.6 (male) × longer than temple in lateral view, 1.1-1.3 × longer than temple in dorsal view. Clypeus hemispherical, ventral margin weakly protruding in lateral view, sharp, truncate; mandibles deflected, labrum broadly exposed. Malar space almost as long as basal width of mandible, malar sulcus complete, deeply incised throughout. Mandible broadening basal-ventrally, but without distinctly delineated basal lobe or tooth. Face variable in sculpture, minimally with strigose band along inner margin of eyes. Occipital carina absent dorsally, the gap less than distance between eyes in dorsal view, carina present and well developed laterally, widely separated from hypostomal carina at base of mandible. Antenna with 43-47 (45 in holotype) flagellomeres, apical flagellomere long and conical. Pronotum dorsally narrow, with median pit; laterally with vertical carina adjacent median vertical groove usually present on ventral 0.3; crenulate along posterior margin, medially varying adjacent the margin from largely smooth to extensively rugulose. Mesoscutum with deep, strongly sloping anterior declivity; notaulus a short, very deep impression barely extending posteriorly beyond anterior declivity; disc of mesoscutum largely bare, without midpit posteriorly; supramarginal carina absent, but base of notaulus rugulose. Precoxal sulcus usually distinct as a broad, shallow, impression, short, not extending to anterior or posterior margins of mesopleuron, always unsculptured; mesopleural fovea crenulate along entire posterior margin of mesopleuron. Propodeum rugulose throughout, short median carina sometimes distinct basally. Hind tibia without basal carina. Fore wing stigma broad, wedge-shaped, relatively discrete distally, r arising from middle; 3RSa 1.3-1.45 × longer than 2RS; m-cu usually interstitial, varying from very weakly antefurcal to weakly postfurcal; 2CUb arising distinctly anteriorad middle of distal margin of 1st subdiscal cell. Hind wing RS largely spectral, weakly pigmented basally; m-cu present as a spectral vein extending nearly to wing margin. T1 with broad, deep laterope but without dorsope; dorsal carinae strongly elevated basally, converging to form a deep basal depression, absent posteriorly beyond spiracle; T1 rugose over posterior 0.5. T2 usually with trace of weakly rugulose sculpture, sculpture sometimes not apparent. Ovipositor (total length) 1.4-1.5 × longer than mesosoma; ovipositor sheath 0.9 × length of mesosoma. Color: dark brown to black; mandible reddish yellow to yellow with apical teeth black; scape, pedicel, remaining mouthparts, legs, and usually T2, 3, 7, 8 yellow; wings hyaline.

Biology.

All of the specimens were reared from the tephritid Strauzia intermedia (Loew) collected from root mines of Rudbeckia laciniata L.

Remarks.

Fischer (1970, 1977) provides a detailed description and keys for this species, all in German. The above diagnosis is intended primarily to highlight features useful for separating Opius peleus from the other species of Opius s.l. treated here. This species is readily distinguished from Opius nympha , Opius taramegillae , and members of the baderae, godfrayi, and pipitae species groups by the presence of extensive sculpturing on the propodeum. Opius yoderi , the only other species described here with an extensively sculptured propodeum, has a densely furry mesoscutum (Fig. 89).

Fischer (1977) placed Opius peleus in the genus Merotrachys , which he defined in part by the presence of sculpture on the second metasomal tergum. In the holotype, the striate sculpture on T2 is more distinct than in the specimens reared from Strauzia in Tennessee. Sculpture is variable in the Tennessee specimens, with some individuals exhibiting virtually no obvious sculpture while others are weakly striate or punctato-striate. In either case, the sculpture in Opius peleus is distinctly different from that found in members of the ingenticornis species group, most of which have previously been included in Merotrachys ( Wharton et al. 2013). Opius peleus also lacks the large pronope and complete dorsal carinae on T1 characteristic of members of the ingenticornis group.

Opius peleus is very similar to Opius antrimensis Fischer but the latter is only 0.5-0.7 × the size of Opius peleus . Details of the facial sculpture, which Fischer (1977, 1979) emphasized as diagnostic for Opius peleus in his keys, are difficult to discern in the holotype and only known specimen of Opius antrimensis . The similarity between these two species suggests the possibility that Opius antrimensis also attacks tephritids or other maggots feeding in roots or lower portions of stems.