DIAPERINI NORTH OF MEXICO TRIPLEHORN 401 



Platydema cyanescens Laporte and Brulle 



Platydema cyanescens Laporte and Brulle, 1831, p. 356. — Horn, 1870, p. 381. 



Description. — Body narrowly oval, moderately convex, deep 

 metallic blue, shining. Head of male with two prominent, parallel, 

 cyhndrical, forward-projecting horns between eyes, a deep depression 

 between them; head of female with sharply pointed tubercles instead 

 of horns, depression between them shallower, antennae and mouth- 

 parts reddish brown, terminal segment of maxillary palpus short, 

 broadly triangular; eyes moderate in size, flattened dorsally, deeply 

 emarginate anteriorly, separated ventrally by a distance of from 2.2 

 to 2.9 (average 2.5) times the longer axis of one eye. Pronotum 

 trapezoidal, strongly narrowed from base to apex, sides nearly straight 

 to slightly arcuate, basal angles rectangular, apical angles narrowly 

 rounded, strongly deflected, marginal bead rather fine, slightly reflected, 

 set off from rest of pronotum by a very narrow flattened area 

 which parallels it, surface uniformly coarsely and densely punctured. 

 Elytral striae feebly impressed, finely punctured; intervals subconvex 

 to fiat, minutely and sparsely punctulate. Prosternal process hor- 

 izontal, prominent; ventral surface of pronotum thickened, flat or 

 convex, coarsely and rugosely punctured; metasternum coarsely but 

 sparsely punctured; basal three abdominal sternites coarsely and 

 densely punctured, especially laterally where they are confluent, 

 forming longitudinal ridges; terminal two sternites minutely punc- 

 tulate, entire ventral surface dark brown to black with legs always 

 a shade or two lighter. Male genitalia with ventral portions of 

 lateral lobes elongate, curved laterally, meeting the basal sclerite as 

 in P. excavatum (pi. 4, fig. 24). Measurements: length 3.4-4.6 mm.; 

 width 1.8-2.6 mm. 



Remarks. — This species shows a close affinity to both P. excavatum 

 and P. teleops. It may be distinguished at once from either of these 

 by the vivid blue color (sometimes tending toward greenish) of the 

 dorsum. In the more narrowly elongate body and the flatness of 

 the elytral intervals, it is strongly suggestive of P. teleops, while in 

 the form and punctation of the pronotum and most other characters 

 it more closely approximates P. excavatum in general facies. 



Type. — Not seen; presumably lost; type localitj^, "Amerique sep- 

 tentrionale." 



Specimens Examined. — From the following localities, 65: 



United States: Alabama (Chickasaw, Mobile, Oak Grove). Florida (Bis- 

 cayne, Crescent City, Dunedin, Enterprise, Fort Myers, Haulover, Lake Mary, 

 Myakka River State Park, Ocala National Forest, Saint Petersburg, Silver 

 Springs). Georgia (Brunswick, Spring Creek, Tybee Island). Indiana (Marion 

 Co.). Louisiana (Covington). Mississippi (Brooklyn, Lucedale, Meridian, 

 Richton). Tennessee (Memphis). Texas (Columbus). 



