SCUTELLEROIDEA OF IOWA 89 
Genus HYMENARCYS Amyot and Serville 
1843. Hymenarcys Amyot and Serville, Hém., 124. 
This small genus containing but four forms is chiefly Ne- 
arctic in distribution. The two species which are found in Iowa 
also enjoy a wide range in North America while the other two 
species have as yet been recorded only from Arizona and Mex- 
ico. The principal diagnostic characters of the genus follow: 
Head only slightly convex on dorsal surface; apex rounded. Rostrum 
extending a little behind midcoxae. Juga without lateral tooth. Bucculae 
gradually increasing in height posteriorly. Pronotum unarmed, the humeri 
rounded but not expanded. Scutellum with apex only moderately nar- 
rowed and not extending posteriorly as far as corium; the latter with a 
distinct and more or less acute apical angle; membrane with nervures ir- 
regularly furcate or reticulate. Odoriferous orifices well outside the coxae 
and not continued in a sulcus. 
Key to the species 
Veins of membrane irregularly fureate but not anastomosing; 
lateral margins of pronotum straight; length, 7.0-9.0 mm. 
PP eo 2 a he Ste ob 6 ood op idl we eceh rele ape aequalis 
Veins of membrane anastomosing; lateral margins of pronotum 
nem ermemorm= O0— 1125 MM... 2... 5 od es os sis ww ele oe NErVOSA 
Hymenarcys aequalis (Say) 
1831. Pentatoma aequalis Say, Deser. Het. Hemi, 7. 
1839. Cimex dentatus Herrich-Schaeffer, Wanz. Ins., V, 64, fig. 607. 
1844. Pentatoma dentatus Herrich-Schaeffer, Wanz. Ins., VII, 95. 
1851. Pentatoma boxura Dallas, List Hem., I, 244. 
1859. Pentatoma aequalis Say, Compl. Writ., I, 319. 
1872. Hymenarcys aequalis Stal, Svensk. Vet. Handl., 10, no. 4, 30. 
1904. Hymenarcys aequalis Van Duzee, Trans. Am. Ent. Soc., XXX, 49. 
General form ovate, narrowed. Color yellowish to pale brown with nu- 
merous, rather large and regularly arranged black punctures. Head long, 
narrow, the median lobe elevated and finely punctate, slightly longer than 
the lateral lobes which are rounded at antero-lateral margins; lateral sub- 
margins more thickly, finely punctured than rest of head. Eyes prominent. 
Antennae yellowish to brownish, thickly covered with small, closely set 
black dots; second and third segments about equal. Rostrum extending to 
posterior coxal border, moderately stout, the third segment somewhat in- 
fuseate, the apical segment black; first and second segments pale yellow 
with black median line. Pronotum more closely and regularly punctate on 
posterior half, the antero-lateral margins almost straight, the edges a little 
roughened anteriorly; humeri rounded, not prominent. Scutellum rounded 
at tip and contracted only moderately before it; irregularly punctate, the 
punctures towards apex a little finer and closer; apex at middle blackish 
with an elongate pale spot on either side. Hemelytra narrower than abdo- 
