(470 ) 



X. On the ficnera Liothrips (oul Hoodia. By Dr. H. 

 Karny of Elboiien, Austria. Translated by G. A. 

 Elliott, F.Z.S., F.E.S. Communicated by R. S. 

 Bagnall, F.E.S., F.L.S. 



[Read February 7th, 1912.] 



In my work on the ThrijJS-gdiWs and the QsiW-Thripidac* I 

 mentioned incidentally that Uzel's genus Liothrips could 

 not be so sharply separated from tlie Gnjp)tothri2JS group as 

 is frequently assumed. In the Cryptothrips group, s. str,, 

 I include the genera Mesothrips, Zimmermann ; Smcrintho- 

 thrijys, Schmutz ; Gynaikothrips, Zimmermann ; Hoodia, 

 Karny; Gryptotlirips, Uzel; and Dcrmothrips, Bagnall. All 

 the above-named genera have the wings of e(;[ual width 

 throughout, and are thus distinguished from the otherwise 

 similar Lcptothrips, Hood, and AndrotJvrips, Karny, in which 

 the wings are somewhat constricted near the middle. 



According to Uzel's synoptic table, the essential differ- 

 ence between Liothrips and Gryptothrips lies in the 

 formation of the mouth. In Liothrips the mouth-cone is 

 "narrowed towards the apex and pointed"; in Gryptothrips 

 and the allied genera it is " apically broadly rounded." 

 These contrasts may, indeed, be easily recognised in 

 extreme cases, but there are many intermediate types. 

 Compare the three figures of Gynaikothrips nzeli, G. 

 chavicae and Mesothrips Jordani.i All three certainly have 

 the mouth-cone "apically rounded," yet they show (especi- 

 ally in Mesothrips) a decided approach to the pointed 

 type. It is evident that, in such cases, it is often difficult 

 to define any distinct boundary between Liothrips and 

 the Gryptothrips group. 



Of all the European genera, Hoodia, Karny, is, in my 

 opinion, undoubtedly the most closely allied to Liothrips, 

 Uzel ; I will therefore say a few words as to these two 

 genera. The special inducement to this is found in the 

 publication by R. S. Bagnall of an English species as 

 Liothrips hradecensis,\ whereas I consider it to be a new 



* Centralbl. f. Bakteriol. Parasit. ii. Infektionskr., ii, Abt. xxx, 

 1911, pp. 556-572. 



t I.e. p. 562. 



X Ent. Mo. Mag., ii Ser., vol. xxi, 1910, p. 256; Joiirn. Econ. 

 Biol, vi, 1911, p. 11. 



TRANS. ENT. SOC. LOND, 1912. — PART II. (OCT.) 



