Azelus Förster, 1869

Taxonomic History / Nomenclature
Azelus Foerster, 1869: 205 Type species: Tryphon erythropalpus Gravenhorst, 1829 [= Ichneumon erythropalpus Gmelin, 1790]. Subsequent designation by Perkins (1962: 409).

Epachthes Foerster, 1869: 205 Type species: Tryphon erythropalpus Gravenhorst, 1829 [= Ichneumon erythropalpus Gmelin, 1790]. Subsequent designation by Viereck (1914: 51) based on two species originally included in Epachtus by Thomson (1894: 1999). Synonymized by Perkins (1962: 421).

Paraplesius Foerster, 1869: 207 Type species: Tryphon erythropalpus Gravenhorst, 1829 [= Ichneumon erythropalpus Gmelin, 1790]. Subsequent designation by Townes et al. (1965: 253). Synonymized by Townes et al. (1965: 253).

Epachtus Thomson, 1894: 1999. Unjustified emendation.

As of 2012, Azelus erythropalpus (Gmelin, 1790), from the Western Palaearctic, is the only valid species included in this genus.
Diagnosis and Relationships
Azelus is recognized by the combination of very short hind tibial spurs and the evenly convex, very blunt and heavily sculptured clypeus. It can be separated from some of the other more robust, heavily sculptured mesoleiines by the short hind wing 1cu-a.
Frons without median horn or elevated carina. Clypeus broad, surface weakly bulging, nearly flat, heavily rugose-punctate (Figs 2, 3); ventral margin blunt throughout, evenly convex; epistomal sulcus shallow, weakly indicated. Malar space (Fig. 2) slightly longer than half basal width of mandible. Mandible (Fig. 3) moderately long, curved, tapering gradually from base to about midpoint, parallel-sided to slightly broadening from midpoint to apex, ventral tooth longer than dorsal tooth. Ocelli small, maximum diameter of lateral ocellus shorter than distance between ocellus and eye. Maxillary palps much shorter than head height. Male antenna slightly longer than body; first flagellomere not much longer than second (Fig. 1). Hypostomal carina joining occipital carina above base of mandible; occipital carina complete. Dorsal end of epicnemial carina extending to anterior margin of mesopleuron or narrowly separated therefrom as in Fig. 5; mesopleuron densely but finely granular punctate ventrally. Notaulus distinctly though not sharply impressed on anterior declivity, weaker on disk but long, broadly converging near posterior margin. Pleural carina complete, varying from weak to well-developed; propodeal carinae mostly obscured by dense, granular sculpture, often with traces of median longitudinal carinae extending from posterior margin. Legs without apical comb on posterior side of hind tibia; hind tibial spurs very short, slender, longest spur less than 0.3 times length of hind basitarsus (Fig. 8); all tarsal claws simple, not pectinate. Fore wing areolet present in two of three specimens examined, completely absent (Fig 9) in the third specimen; stigma (Fig. 9) narrow, with Rs+2r arising slightly basad midpoint; 1cu-a often interstitial with Rs+M. Hind wing (Fig. 9) with first abscissa of CU1 about 4 times longer than 1cu-a. T1 (Figs 6, 7) broad, gradually widening posteriorly; dorsal carinae distinct near deep basal depression for dorsal tendon attachment, in one of three specimens indicated as low, rounded ridges extending to or slightly posteriorad level of spiracle, present only basally in other two specimens; dorsal-lateral carina well-developed basad spiracle, difficult to distinguish among heavy sculpture posteriorly; glymma deep, broad basally, narrowing posteriorly. S1 short, extending about 0.35 times length of T1. T2 thyridium present; laterotergites of T2 and T3 completely separated by creases. The only known species is fairly robust compared to the slender species of Alexeter.

The above description is based in part on Townes (1970) but largely on three male specimens: two from the Texas A&M collection and one from the Canadian National Collection.

1. Azelus erythropalpus habitus, m...
2. Azelus erythropalpus face and clypeus...
3. Azelus erythropalpus mandibles and clypeus...
4. Azelus erythropalpus mes...
5. Azelus erythropa...
6. Azelus erythropa...
7.Azelus erythropalpus T1
8. Azelus erythropalpus hind leg...
9. Azelus erythropalpus wings...
10. Azelu...
No referenced distribution records have been added to the database for this OTU.
Biology / Hosts
Parastioids of Dolerus (Tenthredinidae). Yu et al. (2012) provide several references.

There are no specimens currently determined for this OTU, or those specimens determined for this OTU are not yet mappable.

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 of the American Entomological Institute and Andy Bennett of the Canadian National Collection for extended loans of the material used for this study. Matt Yoder provided considerable assistance with databasing issues, and our use of PURLs ( in this regard follows the example of their use in publications by Norm Johnson. Heather Cummins, Andrea Walker, Patricia Mullins, Caitlin Nessner, Mika Cameron, Karl Roeder, Danielle Restuccia, 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 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, 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.