The Wharton Lab

Pantorhaestes Foerster 1869: 206. Type species: Tryphon xanthostomus Gravenhorst, 1829. Subsequent designation by Viereck (1914: 110).

Trophoctonus Foerster 1869: 206. Type species: Tryphon xanthostomus Gravenhorst, 1829. Subsequent designation by Viereck (1914: 150), selected from one of two species originally included by Thomson (1894: 1999-2000).

In his designation of the type species for Pantorhaestes, Viereck (1914) cites a 1909 publication (neglecting to give the author, though the citation is of a paper by Roman) as the first to include species in Pantorhaestes. Perkins (1962: 443), however, attributes the first inclusion of species in Pantorhaestes to Pfankuch

The following valid species were included by Yu et al. (2012) for this holarctic genus of tenthredinid parasitoids.

Pantorhaestes assiduus (Cresson, 1868)
Pantorhaestes hispanicus Schmiedeknecht, 1913
Pantorhaestes xanthostomus (Gravenhorst, 1829), with lots of synonyms including presently recognized subspecies.

Pantorhaestes belongs to a group of Euryproctini with relatively short T1 and relatively short first flagellomere (in both cases relative to the longer, narrowed features characteristic of genera such as Hadrodactylus). Within this group, Pantorhaestes is characterized by the sharply margined clypeus, the long, broad, sharply margined petiolar area of the propodeum, and the presence of a fore wing areolet. The differences in the clypeal features noted by Schmiedeknecht (1913: 2800) and Townes (1970: 129) in their keys separating Synomelix from Pantorhaestus are subtle. In the material available for examination, the species of Pantorhaestes have a shorter petiolar area on the propodeum, with the broadened section between the median longitudinal carina extending less than half length of the propodeum. T1 also appears narrower in Pantorhaestes.

Clypeus (Figs 2-5) of medium width, not as narrow as in Synomelix, with surface finely punctate; ventral margin sharp, weakly impressed, more or less truncate to weakly medially, weakly angled towards face laterally, giving overall impression of either weakly convex (Figs 2, 4) or subtruncate (Figs 3, 5) ventral margin; epistomal sulcus narrow, weakly to sharply impressed; clypeus in profile (Fig. 6) weakly bulging. Inner eye margins parallel. Malar space (Figs 2, 3) well-developed, varying from 1.0 to about 0.5 times basal width of mandible; malar sulcus absent. Mandible (Figs 4, 5) tapering gradually from base to apex; dorsal tooth broader and about equal to or slightly longer than length of ventral tooth; ventral margin distinctly carinate. Maxillary palp shorter than height of head; antenna (Fig. 1) about equal in length to body, first flagellomere short relative to species in genera such as Mesoleptidea and Hadrodactylus. Ocelli medium-sized, diameter of lateral ocellus about equal to distance from lateral ocellus to eye. Hypostomal carina meeting occipital carina distinctly above base of mandible; occipital carina complete dorsally. Epomia present, though sometimes weak. Epomia present or sometimes obscured by surrounding sculpture. Epicnemial carina usually reaching anterior margin of mesopleuron. Notaulus present as a deep, distinct impression on anterior declivity (the depression sometimes sculptured as in Fig. 7), variable posteriorly: becoming distinctly weaker and very shallow on disk in some specimens, not or only barely extending to level of tegula, but usually extending posteriorad level of tegula as a shallow impression and in some species relatively deeply impressed. Groove between propodeum and metapleuron absent to very weakly indicated, not u-shaped as in pionines; pleural carina present, strongly elevated; median longitudinal carinae very well-developed, forming flask-shaped median section with rugulose petiolar area broad and distinct, extending over approximately posterior 0.3 of propodeum, petiolar area and much narrower areola often delimited by transverse sculpture; lateral longitudinal carina sometimes weaker than median longitudinal carina, extending at least to spiracle from posterior margin, transverse carinae sometimes completely absent, often present at least between median longitudinal carinae. Legs with apical margin of mid tibia expanded into a tooth that is not as well-developed as that of fore leg; apical comb on posterior side of hind tibia weakly developed to absent; posterior hind tibial spur equal to or less than 0.5 times length of hind basitarsus (Fig. 1); tarsal claws not pectinate; fifth tarsomere of hing leg normal, not unusually elongate (relative to fourth) (Fig. 1). Fore wing (Fig. 8) with areolet present; stigma moderately broad, Rs+2r arising at or slightly basad midpoint. Hind wing (Fig. 6) with first abscissa of CU1 longer than 1cu-a. T1 (Figs 1, 9, 10), narrower and not as strongly expanding posteriorly as in Synomelix; ventral margin straight in profile; dorsal carinae present, very well-developed, extending to about level of spiracle in some species, extending about 0.5 times distance between spiracle and posterior margin in other species; basal depression at dorsal tendon attachment broad, shallow; dorsal-lateral carina complete between spiracle and apex of T1; glymma absent. S1 extending to level of spiracle or nearly so. T2 with thyridium usually distinct. Laterotergites of T2 and T3 separated by creases from median tergite. Ovipositor and sheath (Figs 1, 11) straight, ovipositor with distinct dorsal, subapical notch (sheath sometimes appearing slightly upcurved in some preparations).

The above description is considerably modified from Townes (1970), and based on numerous specimens in the Texas A&M University collection.

This page was assembled by Bob Wharton as part of a larger collaborative effort on the genera of Ctenopelmatinae. 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 thank David Wahl of the American Entomological Institute and Andy Bennett of the Canadian National Collection for extended loans of material used in this study. We also thank David Wahl for useful feedback throughout our study. 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, Amy James, Mika Cameron, Danielle Restuccia, and Cheryl Hyde graciously assisted us 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 nos DEB 0723663, 0822676, 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 DEB 0723663, 0822676, 0923134, and 1026618. 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.