169 



Dorsal sclerite of labrum dark brown; median depression not darker or 

 only slightly darker than other surface; setae 5 and 6 dark brown; seta 

 3 yellowish, other setae light, as in species just described. 



Mandibles black, resembling those of G. atomarius, less short than 

 in G. signatipennis; right mandible with 4 distal teeth, left mandible with 

 3; chaetoids of median brushes light yellow, relatively large; lateral setae 

 as in other species of Grammotaulius, small, light, dorsal seta 

 slightly larger than ventral. 



Maxillolabium as in G. a t o m a r iu s, sclerites and setae slightly darker; 

 base of palpifer and mentum reddish black; setae of submentum reddish 

 brown. 



Pronotum brown; groove in anterior third slightly dark in middle; 

 anterior margin narrowly reddish black; stripes of posterior and lateral 

 margin of posterior -angle process the same; punctation distinct, 

 chestnut brown. Mesonotum mainly brown, its posterior angles broadly 

 light brown; anterior margin laterally with a narrow, reddish brown 

 stripe; posterior margin with distinct, narrow, reddish black stripe and 

 small, brown, lateral cross stripes; margin black at posterior angle. 

 All large setae black. 



Tergites of metathorax pale, indistinct; sides of metanotum with 

 chestnut brown sclerotized dots behind anterior median tergites. Setae 

 black, anterior, anterior -angle, and medioanal primary setae longer 

 than the others. 



Number and arrangement of gills of G . n i t i d u s 



Segment 



Dorsal 



Pleural 



Ventral 



2 



3 

 3 



3 



3 



3 

 3 



3 



3 

 3 



3 



3 



3 

 3 



4 



3 

 3 



3(2) 



3 



3 

 3 



5 



2 

 2 



2 



o 



3 

 3 



6 



2 

 2 







2 



3 

 3 



7 



2 

 2 







2 



3 

 2 



8 



2 

 











2 

 



Propleuron chestnut brown, with black pleural groove; pleurites of meso- 

 and metathorax slightly lighter, pleural suture black apically, reddish brown 

 basally; punctation and chaetotaxy as in G. atomarius. 



Prosternite distinct, pentagonal, thin, brownish, dark at posterior margin, 

 with dense, lateral groups of chestnut dots posteriorly. Mesothorax 

 ventrally with similar dots laterally on posterior margin. 



210 



