210 PROC. ENT. SOC. WASH., VOL. 23, NO. 9, DEC., 1921 



MELANOTUS HYSLOPI N. SP. (COLEOP.). 



BY R. H. VAN ZWALUWENBURG. 



The species herein described has been found so often in 

 material submitted for determination that it has seemed 

 advisable to publish this description in advance of a mono- 

 graphic revision of the genus. 



Melanotus hyslopi, n. sp. 



Male. 11.5 mm. long, 3.0 mm. wide. Slender elongate; dark chestnut 

 brown. Pubescence grayish white, moderately thick, coarse, short, recumbent. 

 Free margin of frons rather acutely rounded, slightly convex and very precipi- 

 tous along its median portion. Parantennal foveae very deep, entering strongly 

 sideways into the cranium behind the anterior face of the parantennal area. 

 Parantennal area prominent, and on a plane distinctly anterior to that of the 

 rest of the fronto-clypeal region; median height of parantennal area about equal 

 to its median width. Mandible with a deep fovea entering sideways near the 

 ba?e of its exterior face. 



Third antennal joint about one-third longer than the 2d; both together about 

 as long as the 4th (1.0-1.33-2.33). Tip of 8th antennal joint attaining the 

 posterior angle of the prothorax. 



Prothorax about as long as wide. Sides of prothorax, including posterior 

 angles, straight and diverging slightly backwards from about the anterior one- 

 third; gently narrowed from anterior one-third to the anterior angles. Punctua- 

 tion of notum of prothorax simple on disc, where it is rather coarse and sparse. 

 Posterior angles unicarinate, the carina strong and diverging slightly from the 

 lateral margin, attaining nearly midway to the anterior angle. Notum ot pro- 

 thorax somewhat depressed, with a posterior, median, impressed line. Sulci 

 well marked, subparallel with lateral margin. 



Scutellum longer than wide. Elytral striae consisting of a single series of 

 well impressed, sublinear punctures. Interspaces nearly flat, sparsely and finely 

 punctate. Elytra as wide at base as posterior angles of prothorax; sides sub- 

 parallel to about middle, thence conjointly narrowed to the apex. Humeral 

 carina not prominent; base of elytron without prominent knob opposite base of 

 4th stria. Sternites of abdomen coarsely and subconfluently punctate. 



Female. Slightly more robust than male. Tenth antennal joint attaining 

 to about apex of posterior angle. Prothorax more transverse than in male. 

 Elytra with sides parallel to beyond middle, thence conjointly narrowed to the 

 apex. Otherwise similar to the male. 



The color varies from light castaneous to deep chocolate brown. The males 

 vary in length from 11.3 mm. to 12.0 mm., the females varying within the same 

 limits. The relative length of the 2d, 3d and 4th antennal joints also varies, 

 the 3d varying from one-fourth to one-half longer than the 2d, and the 4th from 

 slightly less than the combined length of the 2d and 3d to slightly more than their 

 combined length. In some males the antennae exceed the posterior angles by 

 only 2 or 1 l / 2 segments. 



Described from 9 males and 2 females: (Males South 



