The Wharton Lab

Sympherta Foerster, 1869: 196. Type species: Tryphon burrus Cresson, 1868. Subsequent designation by Viereck (1914: 140).

Stiphrosomus Foerster, 1869: 198. Type species: Ichneumon fuscicornis Gmelin, 1790. Subsequent designation by Viereck (1914: 139). Preoccupied by Stiphrosomus Fieber, 1858. Synonymized with Trapezocora by Perkins (1962: 453, 458) and with Sympherta by Townes et al. (1965).

Trapezocora Foerster, 1869: 208. Type species: Mesoleptus antilope Gravenhorst, 1829. Subsequent designation by Perkins (1962: 458). Synonymized with Sympherta by Townes et al. (1965).

Atrestes Foerster, 1869: 209. Type species: Catoglyptus sulcatus Thomson. Subsequent designation by Perkins (1962). Synonymized with Trapezocora by Perkins (1962: 408, 458) and with Sympherta by Townes et al. (1965).

Campogenes Foerster, 1869: 209. Type species: Mesoleptus antilope Gravenhorst. Subsequent designation by Perkins (1962). Synonymized with Trapezocora by Perkins (1962: 412, 458) and with Sympherta by Townes et al. (1965).

Provancherella Dalla Torre, 1901: 305. Type species: Baryceros rhopalocerus Provancher [= Sympherta burra (Cresson)]. Monobasic.Townes et al. (1965).

Eustiphrosomus Hincks, 1944: 34. Replacement name for Stiphrosomus Foerster, 1869, not Stiphrosomus Fieber, 1858. Synonymized with Trapezocora by Perkins (1962: 458) and with Sympherta by Townes et al. (1965).

The history of usage of the genus-group name for this group of species is interesting, and rationale for use of Sympherta is not straightforward. Dalla Torre, 1901 kept all 5 of Foerster’s genera as valid, but only included species in Sympherta and Stiphrosomus. Viereck (1914) designated type species for Sympherta and Stiphrosomus, but simply noted that no species had yet been included in the other three genera. Townes (1945) included Sympherta, Stiphrosomus, and Provancherella as synonyms of Pion Schiodte. Perkins (1962) followed Townes (1945) and retained Sympherta as a junior synonym of Pion while noting that the inclusion of North American species in Pion needed investigation. Perkins (1962) placed the other Foerster genera listed above as junior synonyms of Trapezocora. Townes et al. (1965) placed Trapezocora as a synonym of Sympherta, resurrecting the later from synonymy with Pion. Given the synonymies in Perkins (1962), Townes et al. (1965) could just as easily have treated Sympherta as a junior synonym of Trapezocora since the two were equally available, but they did not. Townes (1970) solidified this synonymy and Sympherta has been accepted as the valid name by Hinz (1991) and others. Townes (1970) also stated that prior to his work, the species had usually been placed in Stiphrosomus.

26 valid species were included by Yu and Horstmann (1997), and two more were described between 1997 and 2012.

As is true for some other species, the type species, S. burra, is sexually dimorphic. The face is pale in males and dark in females (Figs. 3 vs. 2 in the description section) and T1 is usually bicolored in males and uniformly pale in females. Male antennae (Figs 7-9) have greatly expanded flagellomeres except at the extreme base and apex, and the color pattern appears to be quite variable (though the possibility of a species complex cannot be ruled out, at least for populations in central Texas). Walley (1937) provides some useful information on some of the New World species. Hinz (1991) revised the Palaearctic species.

Sympherta is readily recognized by the combination of a needle-like ovipositor in the female; absence of a glymma on T1; T1 long, narrow and parallel-sided at least over basal 0.5; mandible long, slender, with distinct basal depression and ventral tooth longer than dorsal tooth; presence of a distinct u-shaped notch between base of lateral longitudinal carina and adjacent portion of metathorax. Sympherta is traditionally (e.g. Townes 1970) separated from Rhaestus on the basis of whether the eyes converge ventrally ( Rhaestus ) or not ( Sympherta ) in frontal view. The eyes are nearly parallel-sided in some Rhaestus, but the mandibles are somewhat shorter and broader in Rhaestus, with the apical teeth more nearly equal in length (compare Figs 1 and 2). In Rhaestus, T1 is also relatively shorter and broader. Sympherta also resembles Asthenara but the species of Asthenara lack the u-shaped groove between the anterior end of the lateral longitudinal carina and the adjacent metathorax.

Clypeus (Figs 2, 3) with surface more or less uniformly finely to densely punctate; ventral margin quite variable, convex in type species (Figs 2, 3), truncate across middle 0.3 in others, and indented in middle of truncate portion in still others, ventral margin broadly to thinly blunt (varying somewhat among species and sometimes between sexes); epistomal sulcus weakly to distinctly deeply impressed though not sharply so; clypeus in profile somewhat convex, not strongly protruding in the type species (Fig. 4) but distinctly protruding when middle of ventral margin indented. Inner eye margins parallel, only rarely very weakly converging. Malar space short but distinct (Figs 2, 3); malar sulcus absent. Mandible (Figs 2, 3, 5) long, relatively narrow, narrowing slightly from base to middle, then broadening to apex; dorsal tooth distinctly shorter than ventral tooth; basal, transverse impression very well developed in all species, usually pit-like (Fig. 3); ventral margin of mandible rounded. Maxillary palp equal to or shorter than height of head; antenna (Figs 6-9) varying from distinctly shorter than body (as in type species) to more nearly equal in length to body in females and males, basal flagellomeres long and slender, usually more so in females (Fig. 6) than males (Figs 7, 8), male flagellomeres medially thickened and/or with unusual setal pattern relative to females. Hypostomal carina meeting occipital carina distinctly above base of mandible; occipital carina complete. Epicnemial carina variable among species, either extending to anterior margin of mesopleuron or not. Notaulus distinct, varying from short and shallowly impressed to longer, deeply and sharply impressed; when well-developed, either extending posteriorly to level of tegula or nearly so or (in a few species), extending much further and merging in a very shallow, posterior depression. Groove between propodeum and metapleuron distinctly u-shaped and usually readily visible; groove mid-dorsally between propodeum and metanotum also distinctly u-shaped and well-developed; pleural carina well-developed, complete; propodeum with median and lateral longitudinal carinae always well developed, median longitudinal carinae usually narrowly separated from one another anteriorly; apical (posterior) transverse carina complete, well-developed; basal (anterior) transverse carina sometimes completely absent, but often with short segment separating areola from basal area, costula always absent, a transverse carina rarely present near spiracle; petiolar area with a median, longitudinal carinae; surface of propodeum varying among species from smooth and polished to extensively rugulose. Apical margin of mid tibia usually expanded into a distinct tooth similar to that of fore leg; apical comb on posterior side of hind tibia absent; posterior hind tibial spur at least 7x longer than maximum width at base (Fig. 1); tarsal claws usually pectinate, but highly variable among species: pectinate nearly to tip on all legs in type species, pectinate only basally in some species, and either absent or very weakly developed (short, weakly thickened setae) at extreme base in others. Fore wing areolet present or absent (about equally divided in species examined); stigma moderately broad, Rs+2r arising near or slightly basal mid stigma. Hind wing with first abscissa of CU1 varying from slightly (nearly equal in type species) to very distinctly longer than 1cu-a. T1 (Fig. 1) long, slender, parallel-sided from base to at least level of spiracles, then either abruptly (type species) or very gradually expanding; strongly (type species, Fig. 1) to weakly decurved in profile; dorsal carinae varying from absent or nearly so in some species (such as the Nearctic S. fucata (Cresson)) to well-developed and distinctly elevated at least to level of spiracles and usually extending to about half distance between spiracles and apex of T1 (as in type species); dorsal-lateral carina variable: absent or nearly so in some species, complete between spiracle and apex of T1 in others; glymma absent. S1 extending full length of parallel-sided portion, barely attaining level of spiracles in a few species (such as the type species), more commonly extending up to 0.3 times its length beyond spiracles. T2 thyridium absent; laterotergites of T2 and T3 separated by creases from median tergite. Ovipositor and sheath (Figs 1, 10) upcurved; ovipositor needle-like apically (for most of its length), a little broader basally, the swollen portion not readily visible without dissection; without dorsal, subapical notch. Cerci visibly protruding in females, about 2-3 times longer than wide.

The following hosts and references for those host records can be found in Yu et al. (2012).

Dolichovespula maculata (Graham 1965)
Macrophya albicincta (Hinz 1961; Weiffenbach 1988; Hinz 1991; Aubert 2000)
Macrophya alboannulata (Hinz 1991)
Macrophya crassula (Hinz 1991)
Macrophya ribis (Hinz 1991)
Pachyprotasis antennata (Hinz 1991)
Rhogogaster chlorosoma (Aubert 2000)
Rhogogaster punctulata (Brischke 1871, 1878; Coulon 1934)
Rhogogaster viridis (Brischke 1871, Coulon 1934)
Tenthredo acerrima (Hinz 1991)
Tenthredo amoena (Hinz 1991)
Tenthredo livida (Hinz 1961, 1991)
Tenthredo rossii (Gyorfi 1947)
Tenthredo rubricoxis (Hinz 1961, 1991)
Tenthredo schaefferi perkinsi (Hinz 1991)

Other hosts have also been recorded as follows:
Dyseriocrania auricyanea (Rohwer 1914; Townes 1945; Barron 1994)
Dyseriocrania grisocapitella (Carlson 1979)

Data on phenology and fecundity were presented by Cummins et al. (2011).

This page was assembled by Bob Wharton as part of a larger collaborative effort on the genera of Ctenopelmatinae, with special assistance on Sympherta from Matt Clark. Page last updated April, 2015.

This work would not have been possible without the groundwork provided by Ian Gauld’s study of the Australian and Costa Rican faunas, and we are particularly grateful for his assistance in many aspects of this study. We also thank the following curators for extended loans of the material used for this study: David Wahl of the American Entomological Institute and Andy Bennett of the Canadian National Collection. We also thank David Wahl for useful feedback throughout our study and particularly Dave Karlsson for sending valuable material from the Swedish Malaise Trap Survey (trap 34, collection event 1092; and trap 22, collection event 1638) and Al Gillogly for material from Idaho. Matt Yoder provided considerable assistance with databasing issues, and our use of PURLs (http://purl.oclc.org) in this regard follows the example of their use in publications by Norm Johnson. Heather Cummins, Andrea Walker, Patricia Mullins, Caitlin Nessner, Amanda Ladigo, and Cheryl Hyde graciously assisted with image processing, formatting, and literature retrieval. This study was supported by the National Science Foundation’s PEET program under Grant No. DEB 0328922 and associated REU supplement #s DEB 0616851, 0723663, 0923134, and 1026618.

This material is based upon work at Texas A&M University supported by the National Science Foundation under Grant Number DEB 0328922 with REU supplements DEB 0723663 and 0923134. 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.