The Wharton Lab

Saotis Foerster, 1869: 210. Type species: Mesoleius (Saotus) brevispinus Thomson, 1883 by subsequent designation of Viereck (1914: 130) based on five species first included by Thomson (1883) though Viereck cited Dalla Torre’s catalog (Dalla Torre 1901) rather than the original work by Thomson.

Saotus Thomson, 1883: 933 Unjustified emendation.

Iskarus Kolarov, 1987. Type species: Iskarus seleuciformis Kolarov, 1987. Monobasic. Synonymized by Kasparyan and Shaw (2003).

Thirty valid species, several of them fairly recently described, were included by Yu et al. (2012). A preliminary key to the European species was provided by Kasparyan and Shaw (2003) but more complete revisions were subsequently published by Kasparyan (2010) and Kasparyan and Kopelke (2010).

Clypeus (Fig. 3) usually narrow, strongly bulging medially, with rounded transverse ridge; ventral margin sharp throughout, deeply impressed medially, rarely with impressed margin at midpoint partly obscured when median bulge extends ventrally to an exceptional extent; ventral margin usually bilobed as in Fig. 3, rarely truncate to more shallowly concave medially, with lateral margins distinctly angled dorsally; epistomal sulcus sharply setting off face from bulging clypeus. Malar space usually distinctly shorter than half basal width of mandible. Mandible (Fig. 3) moderately long, curved, gradually narrowing from base to middle, usually weakly expanding from midpoint to apex; less commonly parallel-sided distally, ventral tooth usually slightly longer than dorsal tooth; ventral margin carinate. Inner eye margins parallel (Fig. 3) to weakly converging. Female ocelli small to very small, with maximum diameter of lateral ocellus distinctly shorter than distance between ocellus and eye. Antennae with relative lengths of first and second flagellomeres quite variable: commonly with first long and slender, nearly twice longer than second as in Fig. 4. Hypostomal carina joining occipital carina well above base of mandible; occipital carina complete. Epomia usually absent. Dorsal end of epicnemial carina usually extending to anterior margin of mesopleuron, less commonly weakly separated from anterior margin; mesopleuron finely mat or polished, finely punctate. Notaulus absent to weakly impressed on dorsal angle of anterior declivity, absent on disk. Pleural carina well-developed dorsoanteriorly, sometimes weak ventroposteriorly; propodeal carinae variable: lateral longitudinal carina varying from present and well developed to nearly absent; lateral margins of petiolar area nearly always well defined, but either open (as in Fig. 8) or closed anteromedially; areola rarely present as a triangle separated from petiolar area and basal median area by transverse ridges, but discrete areola usually absent; median longitudinal carinae often absent between petiolar area and anterior margin of propodeum. Legs with apical comb on posterior side of hind tibia present, not dense; hind tibial spurs slender (Fig. 1), roughly equal in length, spurs about 0.4-0.5 times length of hind basitarsus; tarsal claws either simple or weakly pectinate. Fore wing (Fig. 5) with areolet absent; stigma short, broad, Rs+2r arising from or near midpoint. Hind wing with first abscissa of CU1 much longer than 1cu-a. T1 (Figs 7, 8) usually short and relatively broad for most of its length, as in Fig. 7; more abruptly widening near base, then very gradually widening posteriorly; dorsal carinae well developed along margins of deep basal depression of dorsal tendon attachment, very low and rounded posteriorly, often extending as traces to level of spiracle, though sometimes distinctly posteriorad spiracle; dorsal-lateral carina often sharp and distinct from spiracle to posterior margin of T1; glymma deep. S1 not extending to level of spiracle, about 0.35-0.4 times length of T1. T2 thyridium present; laterotergites of T2 and T3 completely separated by creases in females of four of the five species examined, T3 pendulous in the fifth species. Ovipositor (Figs 9, 10) short, straight, with deep subapical, dorsal notch; ovipositor sheath short and broad (relatively shorter and broader than in species of most other genera of mesoleiines but not all and even slightly variable within Saotis. Apex of female metasoma as in Figs 9, 10. The female metasoma is usually compressed, at least apically, and often more extensively as in Fig. 2; female subgenital plate thus often appearing folded along midline; setae on subgenital plate short and erect as in Himerta and Euryproctus. With one notable exception, the species tend to be small.

This description is considerably modified from Townes (1970) and based largely on females representing five species in the Texas A&M University Collection.

Known hosts for members of this Holarctic group are tenthredinid sawflies that are gall makers on Salix (willows) Kasparyan and Kopelke (2010).

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 are also grateful to David Wahl of the American Entomological Institute and Andy Bennett of the Canadian National Collection for extended loans of the material used for 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 this page and Dave Karlsson for access to material from the Swedish Malaise Trap Survey (Trap 22, collection event 1638 for S. compressiuscula). 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, Karl Roeder, 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 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.