NO. 3568 MELANOTUS QUATE AND THOMPSON 51 



30. Melanotus infaustus (LeConte) 



Figures Gi, lli,j; Plate lo 



Cratonychus infaustus LeConte, 1853, p. 478. 



Melanotus infaustus. — Candfeze, 1860, p. 357. — Thomas, 1941, p. 260. — Severin, 

 1949, p. 17.— Fattig, 1951, p. 21. 



Male. — Body color reddish brown, covered with whitish vestitm-e 

 evenly distributed over body. 



Head: Front with pair of shallow, anterolateral, transverse depres- 

 sions, margin dark reddish brown, thin and strongly protuberant 

 above clypeus, flattened anteriorly and straight when viewed from 

 above; parantennal fovea small, but w^ell defined, arc shaped, and 

 depth about equal to width of opening; nasale as wide as high, slightly 

 protuberant. Mandible with deep slitlike pit. Antenna exceeds tip 

 of hind angle by about 1]^ segments, reddish brow^n, ratio of segments 

 2:3:4 = 3:6:9, segment 4 about 1}^ times as long as maximum u^dth; 

 erect male hairs short and only moderately dense. 



Pronotum about as long as wide, punctm-es at center usually 

 separated by distance equal to or less than owm diameter, subequal to 

 those on front, sides of pronotum straight behind anterior curvature, 

 nearly parallel; hind angles divergent, carina usually extending slightly 

 cephalad of base of hind angle. Genitalia as figured; paramere with 

 apical blade. 



Elytron: 5.5-7.6 mm. 10 spec. 



Female. — Antenna exceeds tip of hind angle by 1 or less segment; 

 internal genitalia as figured, bursa with large patch of spines anteriorly 

 and few, scattered ones posteriorly, spines teardrop shaped, spermathe- 

 cal duct and accessory gland originate close together on bursa. 



Elytron: 6.5-7.5 mm. 3 spec. 



Types. — Lectotype of infaustus: Male, labelled with orange circle 

 "Ga." (MCZ 2518). First specimen of type series selected as lectotype 

 by authors in 1962. 



DisTEiBUTioN. — Florida, Georgia, Indiana, Illinois, Kansas, South 

 Dakota, and Texas. 



Indiana: Tippecanoe; June. Illinois: Whiteside; May. Kansas: Douglas, 

 Reno; June. South Dakota: Brookings, Lake; June, July. Texas: Big Bend 

 Nat. Pk., Bexar, Kerr; March, June. 



M. infaustus appears to be a rare species seldom seen in collections. 

 It is difficult to identify positively unless the genitalia are dissected. 

 Undissected specimens may be confused with the more common tenax, 

 trapezoideus , and prasinus in the Midwest and South or with lanceatus 

 in Texas. The slender thorax is helpfid in separating it from other 

 species, except lanceatus, but positive identification requires a study 

 of the distinctive genitalia. 



