The Wharton Lab

Hyperbatus Foerster, 1869: 210. Type species: Mesoleius segmentator Holmgren. Subsequent designation by Townes et al. (1965: 263). Monobasic.

Hyperbatus is Holarctic. The following 6 valid species were included by Yu et al. (2012):

Hyperbatus aemulus (Holmgren, 1857)
Hyperbatus marmoratus Luhman, 1981
Hyperbatus orbitalis (Thomson, 1894)
Hyperbatus segmentator (Holmgren, 1857)
Hyperbatus sternoxanthus (Gravenhorst, 1829)
Hyperbatus subtilis (Holmgren, 1857)

Hyperbatus was separated with difficulty from Campodorus in the key to mesoleiine genera by Townes (1970), where emphasis was placed on the relatively longer metasoma (terga IV and following “about as long as hind femur” in the female) and two other characters that vary among the species of Campodorus that we have examined. Townes (1970) included only one valid species in Hyperbatus, but five others were subsequently placed there, including one Nearctic species, described as new by Luhman (1981). Kasparyan (1998) provided commentary on the Palaearctic species and stated that the boundaries of Hyperbatus were well-defined by Thomson (1895). We suspect that continued recognition of Hyperbatus will require transfer of some of the species currently residing in Campodorus to Hyperbatus.

Clypeus of moderate size, neither very narrow nor very wide, broadly bulging medially; ventral margin sharp except medially where sharp margin overlapped by blunt median bulge; ventral margin thus having a bilobed appearance as in Campodorus, with sharp lateral margins distinctly angled dorsally; epistomal sulcus sharp and distinct. Malar space equal to or a little shorter than half basal width of mandible. Mandible moderately long, curved, gradually narrowing from base to distad midpoint, then more or less parallel-sided to apex; ventral tooth varying from slightly shorter to slightly longer than dorsal tooth; ventral margin carinate. Inner eye margins parallel. Ocelli small, with maximum diameter of lateral ocellus distinctly shorter than distance between ocellus and eye. Hypostomal carina joining occipital carina well above base of mandible; occipital carina complete. Epomia absent or sometimes present. Epomia present. Dorsal end of epicnemial carina extending to anterior margin of mesopleuron but weak near margin; mesopleuron ventrally coarsely punctate. Notaulus weakly impressed on dorsal part of anterior declivity. Pleural carina complete, well-developed; propodeum with lateral longitudinal carina very well-developed, complete or nearly so; median longitudinal carinae forming part of a broad, rounded petiolar area then extending anteriorly as narrowly spaced, somewhat irregularly parallel-sided ridges; areola confluent with basal median area. Legs with apical comb on posterior side of hind tibia present but poorly developed; hind tibial spurs usually long, slender, about 0.4 times length of hind basitarsus; all tarsal claws simple. Fore wing with areolet absent. Hind wing with first abscissa of CU1 longer than 1cu-a. T1 not long and slender; gradually widening posteriorly; basal depression for dorsal tendon attachment deep; dorsal carinae well-developed basally, extending posteriorad level of spiracle to 0.3-0.5 times distanct between spiracle and posterior margin of T1; dorsal-lateral carina sharp and distinct from spiracle to apex; glymma deep, broad basally, narrowing posteriorly. S1 almost extending to level of T1 spiracle. T2 thyridium present; laterotergites of T2 and T3 completely separated by creases. Ovipositor fairly short, straight or weakly decurved, with subapical, dorsal notch. Ovipositor sheath shorter than posterior hind tibial spur. Female metasoma more elongate than in the otherwise similar Campodorus.

This description was modified from that given by Townes (1970).

A parasitoid of Tenthredinidae. Eller et al. (1989) recorded H. marmoratus as the most common parasitoid of Pikonema alaskensis (Rohwer) in their Minnesota (USA) sample site, and discussed diapause in the host and its parasitoids. Host records for Hyperbatus sternoxanthus include some lepidopterans and these should be regarded as suspect.

This page was assembled by Bob Wharton as part of a larger collaborative effort on the genera of Ctenopelmatinae. Page last updated May, 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 David Wahl for useful feedback throughout our study as well as Al Gillogly for collecting several species useful for composing these pages. 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, Caitlin Nessner, Mika Cameron, and Danielle Restuccia 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 and 0923134.

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.