473 



THE AUSTRALIAN APPLE LEAFHOPPER {TYPULOCYBA AUSTRALIS 



Fvogg.). 



Bv J. G. Myeks^ F.E.S., Biology Seetiou, N.Z. Dept. of Agriculture. 

 (Communicated by Dr. R. J. TiUyard.) 

 (Four Text-figures). 



In the Agricultural Gazette of New South Wales, 'Vol. 29, p. 5U8, 1918, 

 Mr. W. W. Froggatt described a Jassid injurious to apple foliage, under the 

 name of Empoaaca atustralis, n. sp. He recognised that the injury his new- 

 species inflicted on apple leaves was different from that of the well-known 

 American Apple Leaf hopper {Empoasca mali Le Baron) which is as yet un- 

 known in Australasia; but he supposed that the Australian species was likewise 

 an Empoaaca. This is not the case. Both species belong to the very well de- 

 lined Cicadellid subfamily, the Euqjteryginae (Typlilocijbinae, Typliloci/bid.aS 

 auctt. ) but the venation of the Australian insect shows it to be a true Typhlocyba 

 (syn. Empoa). These differences may be summed up as follows: — 

 Wing (hindwing, the forewing being known as the tegmen) with submarginal 



vein Empoasca Walsh 



Wing without submarginal vein T yphlocyba Gerraar. 



This character shows very well in Froggatt's excellent flgiire (I.e.). Em- 

 poasca mali Le Baron indicates its presence "by the characteristic curling of the 

 terminal foliage. This resembles the contortion' caused by an attack of the 

 green apple aphis (Aphis pomi) and consists of the incurling of the end and 

 tlie edges of the leaf with a consequent puckering of the upper surface." This 

 species also causes wilting of early potatoes. 



On the other hand, the injury caused by Typhlnci/ba omtralis Frogg. is very 

 similar to that of its very near relatis'e T. roaae Linn, which occasionally attacks 

 apple in North America. The apple leaves become "variegated with yellow 

 spots" which spread to form irregular patches, giving the whole leaf a dis- 

 coloured appearance and eventually killing it. In contradistinction to Em- 

 poasca, this species shows no preference for young leaves and shoots but rather 

 for old foliage. 



Tijphloe>/ba anstralis has been introduced into New Zealand where it does 

 consideralile damage to apple trees in the orchard districts of Auckland (North 

 Island) and of Nelson (South Island). 



The insect is characterised as follows : — 



Vertex and prnnotum briglit sulphur yellow; eyes usually blackish. S'cutel- 

 lum bright yellow, often with deeper yellow patch on each side of base. Tef/mina 

 of the same bright yellow tint, the membrane iridescent and hyaline. Wings 

 hyaline. Underside uniform yellow. Froiis yellow. Vertex approximately 

 twice as broad as medianly long; fore border rounded. Pronotum trapeziform. 



