12fi2 FAMILY LV. — TENEBEIONID/T:. 



XIX. Platydema Lap. 1831. (Gr., "hroad +body.") 



Small or medium-sized, broadly oval convex speeies having the 

 first joint of hind tarsi longer than the two following together; 

 epipleurse entire; mesostemum concave; last joint of maxillary 

 palpi broadly triangular, its inner and outer sides nearly equal; 

 intereoxal process of abdomen triangular, acute. They occur es- 

 peciall}' on fleshy fungi about the base^ of stumps or trees or be- 

 neath bark. About 16 species are known from the United States, 

 ten of which arc known from Indiana, while another may occur. 



KEY TO INDIANA SPECIES OF PLATYDEMA. 



n. Hend with iKirns or tubercles; fi'oiit concave. 



6. Tipper surface black, shining. 2332. excavatum. 



hb. Upper surface iJiceous or dark reddish-bi'own, ojiaque. 



2333. EEYTHROCERA. 



(in. Head without tubercles or horns. 



c. Thora.x dull red, cl.vtra black. 23.S4. buficoi.le. 



cc. Thorax and elytra black. 

 (/. Surface opaque. 



e. Elytra without red spots. 



/. Antennae wholly pale. 12335. euficorne. 



//. Antenna} black, three basal joints pale. 2336. flavipes. 



ce. Elytra each with an oblique red siKit on basal half. 



2387. EixiPTiciM. 

 dd. Surface shining black. 



.'/. Prosternum horizontal, its apex prominent. 

 n. Head with distinct transverse groove and frontal impressi ,ii. 



AMERICA MM. 



hh. I-Iead without transverse impression. 



;". Thorax very sparsely punctured. 2338. l.f.vipes. 



ii. Thorax and intervals of elytra densely punctured. 



2.'!.39. iMICANS. 



l/p. Prosternum convex between the c(ix;e, its apex deflexed and ob- 

 tuse. 

 ./. Elongate-oval; black with a bronzed tinge; smaller, not ovei- 



5 """■ 2340. PTniAHRUM. 



jj. r.r(jadly oval; larger, r>-7 mm. l>,34t. sudcostati'm. 



*2;;:!2 (T.^IO). IM^atydema excavatu.m Say. .Tcmrn. Phil, Acad. Nat Sci.. 

 in, 1X24, 207; Ibid. II, 157. 

 Broadly oval, convex. Black, shining; anteunre and legs reddish-brown, 

 the latt<.r sometimes piceous. Head of male with two parallel, pvonuneut. 

 cylindrical horns between the eyes; front deeply concave betwcn the bases 

 of the horns ; head of female with tubercles instead of horns. Thorax more 

 than twice as wide as long, narrowed from base to apex, surface finely and 

 sparsely punctate. Elytra with rather finely punctured stria? ; intervals fee- 

 bly convex, minutely punctured. Length 4.5-5.5 nun. 



Throughout the State; common. January H-Octobor 14, 



