(476) 



Number and arrangement of gills of M . n i g r a 



Segment 



Dorsal 



Ventral 



2 



1 





3 



1 





4 



1 





5 



1 





Full-grown larva. Length 8.5 — 11.3 mm; resembling M. longicornis, 

 but darker. Frontoclypeus with a broad, black, transverse stripe covering 

 1st pair of dots anteriorly; 2nd pair of dots situated immediately behind 

 stripe; 3rd pair formed by small dots, sonaetimes only on one side or absent; 

 476 band in the posterior part wide, black, situated behind a light median stripe 

 and before a wide, oval process. Dorsal stripes black, distinct, connected 

 with lateral stripes and with wide stripes lateral to coronal suture; 

 connections between stripes dark brown; dark dots posteriorly at margin of 

 lateral stripes; ventral surface with short, black stripes covering dots 

 posteriorly. Gula brownish, lighter laterally, sometimes dark only at 

 anterior and posterior margin. 



166 



167 



FIGURES 766 and 767. Mystacides nigra L. Pupa: 

 766 -holding apparatus, segments 5 and 6; 767 — anal rod. 



Pattern of pronotum as in M. longicornis, but black stripes and spots 

 wider; ground color light brown, slightly darker than in M. longicornis 

 in dark specimens; anterior angles with distinct, light stripe; dark part of 

 lateral area uniformly black before and behind stripe, without dots; dots 

 present only at margin of posterior branch of wide, bracketlike, median 



596 



