(i2 SMITHSONIAN MISCELLANEOUS COLLECTIONS VOL. 1 37 



INTRODUCTION 



The South American semiaquatic grasshopper Marellia remipes 

 was described by Uvarov (1929) from a single female specimen from 

 Parana (province of Entre Rios, Argentina) sent to him by Dr. Car- 

 los A. Marelli. Several closely related species of the same genus were 

 subsequently discovered in different parts of South America : Marellia 

 clearei Uvarov, 1930, from British Guiana; M. paludicola Guenther, 

 1940, from eastern Peru, and M. geyskeia Willemse, 1948, from 

 Surinam. The male of Marellia remipes was described almost simul- 

 taneously by Liebermann (1940) and Rosas-Costa (1940) more than 

 a decade after Uvarov's description of the female. 



In his original description of Marellia remipes, Uvarov (1929) 

 states that this newly discovered genus of insects presents obvious 

 adaptations to semiaquatic life, as revealed by the remarkable ex- 

 pansion of the hind tibiae. He also points out the peculiar structure 

 of the apical portion of the abdomen and the ovipositor, remarking 

 that they suggest a very unusual habit of oviposition. 



A number of authors have published later reports on this curious 

 genus of grasshoppers, or have made reference to it in general works 

 of acridiology. Uvarov (1930), Chopard (1938), Liebermann (1940), 

 Rosas-Costa (1940), Rosillo (1940, 1941), and Willemse (1948), 

 verify the semiaquatic habits of Marellia, stating that the insects live 

 on aquatic plants and swim easily, both on the surface and under 

 water, being able to spend considerable time submerged among the 

 aquatic plants, to the stems of which they cling to avoid floating back 

 to the surface. 



Of the papers referred to in the preceding paragraph, those of 

 Rosillo (1940) and Willemse (1948) are particularly illustrative of 

 the habits of the insects of this genus. Rosillo observed Marellia re- 

 mipes near the city of Parana (Entre Rios, Argentina) living on 

 aquatic plants in shallow waters of the Parana River. According to 

 this author, the plant preferred by the insect at this particular place is 

 Hydromystria stolonifera IMay. (Hydrocharitaceae), a plant with 

 round or oval floating leaves on which the insects live and feed. He 

 describes for the first time the peculiar feeding habits of these in- 

 sects, which gnaw holes on the surface of the leaves instead of eating 

 them from the edges as do other grasshoppers. 



In the other paper Willemse transcribes observations on Marellia 

 clearei communicated to him by Dr. D. C. Geyskes of Paramaribo 



