A NEW GENUS OF THE TRIBE MESOSTENINI FROM 
CHILE (HYMENOPTERA, ICHNEUMONIDAE)* 
By Charles C. Porter 
Biological Laboratories, Harvard University 
In my work on the Chilean Mesostenini it early became evident 
that the Cry plus cyanipennis of Brulle, one of the most striking and 
easily recognizable of the described mesostenines of temperate South 
America, is sufficiently distinct from other known forms to deserve 
separate generic status. I therefore give below a description of this 
new genus together with a brief discussion of its affinities and a 
redescription of the type species. 
Xiphonychidion, new genus 
Head transverse, temples strongly receding behind the eyes. Frons 
unarmed. Face gently convex between insertion of antennae and 
clypeus. Clypeus strongly convex, bluntly pyramidal in profile, the 
apical margin truncate, without a tooth. Antennae subequal to body 
in length, not at all thickened medially, subapical part of female anten- 
nae scarcely flattened below, white-annulate well beyond middle in 
both sexes. Epomia strong, with a little swelling above. Mesoscutum 
broadly convex, mat, with gross transverse foveolations arranged in 
roughly longitudinal series between which are much more finely 
sculptured areas; notaulus obsolete, not extending far beyond middle 
of mesoscutum, most clearly defined basally where it is a broad foveo- 
late depression. Scutellum low, gently convex. Propodeum grossly and 
rather regularly rugoso-reticulate throughout, basal trans-carina com- 
plete ; areola rather weakly to quite strongly delimited, smallish ; apical 
trans-carina obsolete except medially, where it borders areola behind, 
forming very strong, blunt sublateral crests; spiracle long-elliptical. 
Wings dark-infumate with purplish reflections. Areolet very large, 
pentagonal, a little higher than wide, intercubiti straight, almost par- 
allel, very slightly converging above; ramellus long and well-devel- 
oped; nervulus postfurcal by about 1/3 its length; median part of 
mediella straight; nervellus broken at about its lower 1/3 in female, 
a little below middle in male; axillus far from anal margin of hind 
wing but distinctly closer to it than to submediella over most of its 
length. First abdominal segment rather slender; postpetiole mod- 
erately expanded, part behind spiracles about 1.0 times as long as wide 
* Manuscript received by the editor December 20, 1962. 
