4-23 



Leptocylindrus miniinus is a boreal, neritic diatom reportedly 

 associated with the spring Thalassiosira bloom in the Gulf of Maine 

 (Lillick, 1940) . L. minimus is difficult to distinguish from L. dani- 

 cus , which was considered a major dominant in Long Island Sound (Cono- 

 ver, 1956; Riley and Conover, 1967) . In New Haven Harbor, a major bloom 

 (10 to 10 cells/liter) of L. minimus occurred during April 1976 

 (Figure 4-9) following a period of consistent dominance that began in 

 September 1975 (Table 4-2) . This species was also dominant during July 

 and December 1974, September/October 1976 and less so during May, Sept- 

 ember and October 1977. 



Dinof lagellates have generally occurred as dominants during 

 late spring and summer in New Haven Harbor (Table 4-2) as has histor- 

 ically been the case for Long Island Sound (Conover, 1956; Riley and 

 Conover, 1967) . In June 1974, a non- toxic red-water bloom of the dino- 

 flagellate Peridinium sp. (which may have been Heterocapsa triguetra = 

 Peridinium triquetrum) was observed. In 1975, dinof lagellates were 

 dominant sporadically only during May and December. During 1976, 

 several dinof lagellates were dominant from April through October; major 

 features were the reoccurrence of a Heterocapsa triguetra bloom in June 

 and blooms of unspecified taxa and Prorocentrum spp. primarily from July 

 through September (Table 4-2) . In 1977, unspecified dinof lagellates 

 were among the ten dominant taxa from March through October, with addi- 

 tional blooms of Heterocapsa triguetra in February (Figure 4-10) , Kato- 

 dinium rotundatum in April (Table 4-2) and July and Prorocentrum red- 

 fieldii in July (Table 4-2) . 



Microflagellates have been consistent dominants in New Haven 

 Harbor, although prior to July 1976 unspecified taxa were probably 

 underestimated during microscopic examination (NAI, 1977) . During 1977, 



for example, unspecified microflagellates were consistently dominant, 



5 6 



with abundances ranging from 3 x 10 to 9 x 10 cells/1 (NAI, 1978). Of 



the microf lagellate taxa identified to genus, two cryptophycean genera 



(Chroomonas sp. and Rhodomonas sp.) appeared as overall dominants in 



1974 through 1975, and a third cryptophycean {Cryptomonas sp.) was an 



overall dominant in 1974 only (Table 4-1) . In 1976 and 1977, Chroomonas 



