a

 

 

 

 

b

 

 

 

c

 

 

 

 

d

 

 

 

 

e

 

 

 

 

 

 

 

 

f

 

Fig. 4. Transitions from the pure albomarginatus courtship song (a) to the pure oschei song (f) through intermediate variants (b-e) recorded in the different hybrid localities. Place and date of the collection: ) Germany, Erlangen, 20.07.1999; b) Ukraine, border betw. Nikolaev and Kirovograd regions, 30.06.1999; c), e) Ukraine, Nikolaev region, Migija, 15.07.2000; d) Ukraine, Nikolaev region, Koblevo, 8.07.1999; f) Ukraine, Odessa region, Semjonovka, 2.07.1999. In each case two upper traces - leg movements, lower trace - sound recording. Drawings of the highest positions of the hind tibiae are shown on the right; the moments when they occur are marked with arrows.