166 Broughton A. Caldwell 



Abdomen. Procerci dark brown, up to 26 long, 17 wide, with a basal 

 curved spur and 2 short median setae. Preapical procercal spur not 

 developed, represented at most by a slight protrusion. Three long and 

 two shorter anal setae; longest seta about 450-500 (3) long. Anal tubules 

 slender, gradually tapering, and about 2.5 times as long as posterior 

 parapods. 



Etymology. — The species is found in Millrock Branch, a stream in 

 Rockdale County, Georgia, that supports a most diverse and interesting 

 chironomid fauna. 



Holotype. — Reared §, with exuviae, Millrock Branch at Haralson 

 Mill Road (83°57'24" N, 30°45'41" W), Rockdale County, Georgia, 3 

 VII 83, leg. B. A. Caldwell. Holotype specimen deposited in the Florida 

 State Collection of Arthropods (Tallahassee). 



Paratypes (9). — Reared 2 (allotype), with exuviae, same data as 

 holotype; reared §, with exuviae, same data as holotype; $ prepared 

 from mature pupa, with exuviae, same data as holotype except 3 VI 82; 

 mature 2 pupa, with exuvium, same data as holotype except 2 VI 78; 2 

 pupal exuvium, same data as holotype except 20 III 82; 2 larvae, final 

 instar, same data as holotype; larva, final instar, same data as holotype 

 except 19 VII 77; larva, final instar, Huffines Mill Creek, Rockingham 

 County, North Carolina, VIII 81, leg. D. R. Lenat. All paratype speci- 

 mens are deposited in the Florida State Collection of Arthropods 

 (Tallahassee). 



Diagnosis. — Males of Paracricotopus niger (Kieff.) and P. uligino- 

 sus (Brund.) are very similar structurally, as has been noted by Albu 

 (1968) and Saether (1980a). Paracricotopus millrockensis is very similar 

 to these two species structurally, and consistent separation may not be 

 possible. I have not borrowed the type material, but differences in these 

 species might be discovered in the structure of the aedeagal lobe and 

 gonostylus. Males of P. millrockensis are separable from those of P. 

 glaber by differences in the hypopygium, especially gonocoxite length, 

 aedeagal lobe size and shape, and gonostylus shape. In the female, P. 

 millrockensis is most similar to P. niger, but differences are found in the 

 genitalia, especially the shape of the coxosternapodeme and the ventral 

 lobe of gonopophysis VIII. In lateral view, prior to embedding in bal- 

 sam, the allotype female was noted to have a thinner notum than that 

 illustrated by Saether (1980a, Fig. 2 A). Also, there are differences in leg 

 lengths and ratios. The larva and pupa of P. millrockensis are separable 

 from the other described species in the genus by several characters. In 

 the pupal stage, P. millrockensis can be separated by the smooth elon- 

 gate thoracic horn, different abdominal chaetotaxy, and different anal 

 lobe. Its anal lobe is very similar to that of P. niger, based upon the 

 figure of Thienemann (1950). Saether (1980a), however, reported 8-15 



