HOW TO KNOW THE INSEQS 



Fig. 125. BolltothoruG cornutus (Panz.) 



Dull bro^jvnlsh black. Thorax and elytra much 

 roughened v/ith large and small Irregular tuber- 

 cles. Llales with two horns as pictured. When 

 disturbed they "play pocDum" and strongly re- 

 semble bits of dry rotten wood or fungi among 

 v/hlch they are found. Length 10-12 mm. 



r^m* ''St^ The Darkling beetles represent a large family. 

 tis'AfVil / ^ large percentage are western forms and not 



found In our area. They vary In size from tiny 

 little fellows to that of some of our largest 

 Figure 125. beetles. A number of species are cosmopolitan 

 pests of grain products. Many of our native 

 species are found under bark. Ov/en J. Smith* has pictured and 

 described the knovm Iowa species. 



35a Head not strongly and suddenly constricted at base. ... 36 

 35b Head strongly constricted at base, being suddenly narrowed 



behind 37 



36a Mesosternum long; epimera of metathorax visible. (The 

 Melandryid Bark Beetles.) Figs. 126 and 133. 



Family 90, MELANDRYIDAE 



Fig. 126. Eustrophlnus blcolor (Fab.) 



Convex. Shiny black, sparsely pubescent. Ab- 

 domen, legs and four basal joints of antennae 

 reddish yellow. Common under bark. Length 

 5-6 mm. 



The members of this comparatively small family 

 are found mostly in fungi and under bark. They 

 are often thickly covered with silken hairs and 

 range in size from 3 to 15 mm. 



Figure 126, 



36b Mesosternum quadrate; epimera of metathorax covered. (The 

 Flat Bark Beetles) Figs. 127, 121 and 130. 



Family 72, CUCUJIDAE 



Fig. 127. Telephanus velox Hald. 



Slender, subdepressed, rather thickly clothed 

 with hairs, pale broivnish-yellow; head and apical 

 ends of elytra darker. The antennae are fre- 

 quently held in the characteristic position 

 pictured. Length about 4 mm. 



Figure 127. 



37a Side pieces of prothorax not separated from the pronotum by 

 a suture. Base of prothorax narrower than elytra 38 



* "A study of the Tenebrionidae of Southeastern lov/a." 0\7en J, Smith. Proc. la. 

 Academy Science. 28: 259-265. 1931, 



69 



