No. 39] ODONATA OF CONNECTICUT: GOMPHIDAE 137 



Ophiogomphus mainensis Packard ^^ 



Proceedings of the Entomological Society of Philadelphia, 2: 255: 1863. 



Nymph. — Labium as in PI. v, Fig. 4; third antennal segment 

 almost oval, the fourth segment rudimentary; dorsal surface of 

 the head minutely tuberculate. 



Thorax : legs short, very hairy, the hind femora each with a 

 glabrous scar on the external surface from base to near the distal 

 end. 



Abdomen : without prominent hooks but with knobs on 2, 3, 

 and 4, those on segments 5 to 9 projecting a little more and resem- 

 bling hooks or teeth, but not reaching the caudal margin of the 

 segments except that of 9 ; lateral spines wanting, but replaced 

 by blunt projections on segments 8, 9 and 10; lateral terminals 

 very wide at base, a little more than half as long as the superiors 

 and inferiors, which are about equal in length ; abdomen in front 

 of segment 10 divided into thirds by two longitudinal impressed 

 lines on the ventral surface. 



Measurements: total length, 23-25 mm.; abdomen, 14-15 mm.; 

 width of abdomen, 7 mm. ; length of hind femora, 4-5 mm. ; 

 dimensions of segment 9, 5 mm. broad by 1.25 mm. long. 



Adult, male. — Color yellow and dark brown or black. 



Head : labrum pale with brown or black margins ; a dark 

 streak on the front at ocelli ; ocellar area dark ; occiput yellow. 



Thorax : yellow, with a dark mid-dorsal stripe, another over the 

 mesopleural suture and another shortly dorsad, which may or may 

 not be united with the sutural stripe ; metapleural suture narrowly 

 lined with black; wings clear, or smoky. 



Abdomen: sides of terga i and 2 pale on sides, 3 pale on sides 

 at base, pale dorsal stripes on 1-3, dorsal streaks or spots on 4-8, 

 sides of 8, 9 and 10 broadly pale, the pale spots sometimes includ- 

 ing a black spot on 8 and 9 ; anal appendages denticulate or tuber- 

 culate below ; arms of the inferior appendage straight, cylindrical, 

 seen from below the apices considerably widened, divided at tips 

 (Fig. 15, C). 



Female (Fig. 15, E). — Occiput as in Fig. 15, A, the spines 

 long and contiguous a short distance from the bases, though vary- 

 ing in this respect, being more nearly parallel or the tips crossed 

 in some preserved specimens; vulvar lamina (Fig. 15, B) nearly 

 as long as segment 9, the median notch a little more than half the 

 length of the plates. 



Measurements : total length, male 42-45, female 43-46 mm. ; 



length of abdomen, male 28-30, female 30-31 mm.; length hind 



wings, male 25-26, female 27-28 mm. ; width of hind wings, male 



7-8, female 8.5-9 ^^^ 



Connecticut. — Litchfield, 4 June, 1925, and various other dates (L.B.W.) ; 

 Milford, 13 June, 1922 (W. E. B.). 

 New England. — May 27-July 11. 



'^^ J ohannus Needham, Can. Ent. 29: 182: 1897. See footnote, p. 134, 



