50 PROCEEDINGS OF THE NATIONAL MUSEUM vol. 121 



29. Melanotus pertinax (Say) 



Figures 6/, lOk 



Elater pertinax Say, 1839, p. 185, 



Cratonychus pertinax. — LeConte, 1853, p. 479. 



Melanotus pertinax. — Candfeze, 1860, p. 359. — Blatchley, 1910, p. 755. — Thomas, 



1941, p. 260.— Dietrich, 1945, p. 58.— Severin, 1949, p. 17.— Fattig, 1951, 



p. 21. 



Male. — Body color black or dark reddish brown and appendages 

 lighter reddish brown (light colored teneral specimens also have 

 appendages paler than body), covered with white vestiture evenly 

 distributed over body. 



Head: Front with pair of shallow anterolateral or transverse 

 depressions, margin narrow and evenly rounded when viewed from 

 above, thick and not strongly protuberant above cljrpeus; parantennal 

 fovea small but moderately deep circular or semicircular, foveal 

 tragus seldom developed; nasale flat, width about 2 tunes height. 

 Mandible with deep, teardrop-shaped pit. Antenna exceeds tip of 

 hind angle by about 1 segment, reddish brown, ratio of segments 

 2:3:4=3:4:5, segment 4 about iKo times as long as maximum width; 

 erect male hairs short and dense. 



Pronotum wider than long, ratio of width/length =1.06-1.20; 

 punctures at center usually separated by distance equal to more than 

 twice own diameter, smaller than those on front, sides of pronotum 

 rounded and concave at base of hind angles; hind angles divergent, 

 carina weak, usually not extending cephalad of base of hind angle. 

 Genitalia as figured; paramere without blade. 



Elytron: 6.4 ±0.4 mm (6.0-7.3). 50 spec. 



Female. — Antennal tip short of pronotum base by 1 segment; 

 internal genitalia as figured, bursa with sparse, scattered peglike 

 spines, accessory gland very short and clavate. 



Elytron: 7.2 ±0.4 mm (6.6-8.1). 27 spec. 



Types. — Types of pertinax: "Mass." Specimens lost. 



Distribution. — Maine to North CaroHna, west to Wisconsin and 

 Illinois. 



Connecticut: Litchfield, New Haven; May, July. Georgia: Clarke; May. 

 Illinois: Champaign, Knox, McHenry, McLean; May, July. Maine: York; 

 July. Massachusetts: Berkshire, Bristol, Hampshire, Middlesex, Suffolk, 

 Worcester; April, August. Minnesota: Hennepin, St. Louis; May, June. New 

 Hampshire: Hillsboro, Strafford; May, July. New York: Columbia, Erie, 

 Putnam, Tompkins, Washington, Wyoming; May, August. North Carolina: 

 Buncombe; June. Pennsylvania: Lycoming; July. South Carolina: Aiken; 

 June. Vermont: No data. Wisconsin: Milwaukee; June. 



That the appendages are of a different color than the body sets 

 pertinax apart from other American Melanotus, since no other species 

 has this coloration. 



