THE SHORT-WINGED SCAYENGEE BEETLES. 



437 



Southern half of State ;. frequent. March 25-May 11. Taken 

 by sifting and from decaying fruit. One of the smallest of Staphy- 

 linids. 



LVI. P^ederus Grav. 1806. (Gr., "a precious stone.") 



Small, slender, convex species, sparsely clothed with erect hairs 

 and having the presternum shortened between and under the coxae, 

 not reaching mesosternum ; neck one-third the width of head, labrum 

 emarginate at apex; last joint of maxillary palpi obtuse; tarsi with 

 the fourth joint bilobed beneath. Three species are known from 

 the State, all colored alike, being reddish-yellow, shining, with the 

 head and last two segments of abdomen black ; elytra dark blue. 



KEY TO INDIANA SPECIES OF P^DERUS. 



a. Elytra much shorter than wide ; distinctly shorter than thorax, sparsely, 

 coarsely and deeply punctate. 837. palustris. 



aa. Elytra subquadrate, at least as long as wide, and as long as or longer 

 than thorax. 



ft. Thorax ovate ; elytral punctures coarse, deep, rather close-set through- 

 out 838. LITTORARIUS. 



f)l). Thorax elongate-oval; elytral punctures shallow, much less coarse 

 and very sparse, obsolete toward apex. 839. obliteratus. 



S37 (2572). PiEDERUS palustris Aust, Proc. Bost. Soc. Nat. Hist., XIX, 47. 



Elongate, slender. Antennae piceous, the apical and four basal joints 

 pale, the outer joints gradually thickened. Head suborbicular, as wide as 

 long, rather coarsely and sparsely punctate. Thorax elongate-oval, slightly 

 narrower than head, very sparsely punctate. Elytra as mentioned in key. 

 the basal angles very broadly rounded. Abdomen as wide as elytra, mi- 

 nutely punctate. Length 4.5-5 mm. 



Starke, Knox and Posey counties; scarce. April 18-June 17. 

 Sifted from debris along the margins of ponds and lakes. 



838 (2573). P^ederus littorarius Grav., Men. Col. Micr., 1808, 142. 



Elongate, slender, subparallel. Antennae piceous at middle, the base 

 and two or three apical joints pale, the outer joints not enlarged. Head 

 slightly longer than wide, base broadly rounded ; surface, as well as that of 

 thorax and abdomen, finely and very sparsely punctate. Thorax convex, 

 slightly longer than wide, a little narrower than head; sides feebly curved. 

 Elytra equal in length to and one-fourth wider than thorax. Abdomen a 

 little narrower than elytra, parallel. Male with the slit of the sixth ven- 

 tral three times as deep as wide. Length 4.2-5.5 mm. 



Throughout the State; common. February 14-November 10. 

 Occurs especially in open woodland. Hibernates beneath and be- 

 tween the leaves of mullein. 



