240 



Notes on Some Miscellaneous Coleoptera, with 

 Descriptions of new Species. -Part IV. 



By Arthur M. Lea, F.E.S., Museum Entomologist. 



[Contribution from the South Australian Museum.] 



[Read October 10, 1918.] 



Plates XXX. to XXXII. 



PSEL APHID AE. 

 Articerus. 



The genus Articerus (like Mandalotus of the Curcu- 

 lionidae and Laius of the Malacodermidae) contains species 

 many of which are characterized by remarkable sexual 

 features. In the male the metasternum is always different 

 from that of the female, being often armed with one or two 

 spines or projections and sometimes largely excavated; the 

 under-surface of the abdomen of the female is usually evenly 

 convex, with the pygidium in the normal position of that 

 organ ; but on the male the abdomen is strongly depressed 

 towards the base, with the apex incurved and the pygidium 

 overhanging ; as a result the sex of a specimen carded in 

 the ordinary way may be distinguished from the side, the 

 female having the metasternum and abdomen almost con- 

 tinuously resting on the card, while in the male there appears 

 a gap (sometimes of great extent) between the tip of the 

 abdomen and the highest point of the metasternum ; the 

 tibiae of the male are often armed and sometimes have curious 

 flanges, the femora and trochanters are also subject to great 

 sexual variation ; but the sexual variation of the antennae is 

 seldom very pronounced. It is desirable to set unique speci- 

 mens so that both surfaces may be closely examined, and in 

 describing new species quite as much attention requires to be 

 paid to the under-surface and appendages as to the upper- 

 surface. At one time several exotic species were referred to 

 the genus, but these have all been excluded by Raffray. 



