440 STUDIES IN AUSTRALIAN ENTOMOLOGY, 



Rhytisternus nigellus, n.sp. 



2. Oblong, depressed ; prothorax subcordate, as wide across 

 apex as across base, sides lightly sinuate towards base ; elytra 

 with four inner strise strongly impressed, entire, fifth weaker, 

 interstices depressed. 



Black ; legs, labrum, palpi and antennae piceous-red. Head 

 small, smooth ; front bi-impressed ; the impressions short, linear, 

 arcuate, divergent behind, their apices connected by the strongly 

 impressed clypeal suture ; clypeus strongly declivous to labrum ; 

 eyes convex, set lightly in orbits at base. Prothorax transversel}'^ 

 cordate (2*4 x 3-2 mm.), depressed on disc, roundly declivous on 

 anterior part of sides ; disc transversely striolate ; sides almost 

 evenly rounded on anterior three-fourths, obliquely straightened 

 (not out-turned) before base ; anterior margin almost truncate, 

 hardly emarginate ; base subtruncate, very lightly sinuate ; 

 anterior angles truncate, not perceptibly advanced ; basal angles 

 sharply marked, rectangular ; lateral border thick ; median line 

 lightly impressed, linear ; two separate lateral basal impi-essions 

 on each side, neither attaining base, the internal having a narrow 

 elongate well-defined course, the external forming a foveiform 

 puncture ; the space between the internal basal impressions 

 depressed, that between external and lateral margin very narrow ; 

 posterior marginal puncture small, placed at extremity of marginal 

 channel. Elytra wider than prothorax (6-8 x 4 mm.), lightly 

 rounded on sides, truncate on base with the shoulders rounded ; 

 apical curve lightly but decidedly sinuate on each side ; strise 

 lightly crenulate, four inner ones entire, strongly impressed, more 

 lightly so towards apex, fifth entire, lightly impressed, sixth very 

 faintly impressed, seventh obsolete ; interstices depressed, ninth 

 punctate, the punctures widely interrupted in middle ; lateral 

 border fine, reflexed ; basal border curved behind on each side ; 

 marginal channel widened a little before the apical sinuosity. 

 Prosternum truncate and bordered on l:)ase ; episterna finely 

 rugulose. Ventral segments obsoletely and very finely punctu- 

 late. 



Length 1 1 -5, 1 )readth 4 mm. 



