339. No enlarged black scale on shoulder; first dorsal fin over three-fourths 



height of second dorsal fin; cheeks blue; sides with blue and orange 



bars; fins blue and orange 340. 



Usually with an enlarged black scale on the shoulder (at base of peC' 



toral fin); first dorsal fin often lower 341. 



340. Gill membranes very slightly connected; males with red coloring on anal 



and tail fins; N. Y. to Minn, and southward in the Mississippi Valley 

 almost to the Gulf 



Oligocephalus caerulens (Storer) Rainbow Darter 

 Poecihchthys caerulens (Storer) 

 Gill membranes slightly overlapping anteriorly; no red coloring on anal 

 and tail fins; Mich, to Virginia and Kansas 



Poecihchthys spectabihs Agassiz, Orange-throat Darter 



341. Scale count usually over 60; gill membranes not connected; belly red; 



Ozark area 



7^^sl^vicola punctulata (Agassiz) 

 (Poecihchthys punctulatus Agassiz) 

 Scale count usually less than 60; gill membranes very slightly connected 



342. 



342. With small dark spots along the middle of each side; fins with reddish 



coloring; Colorado and Kansas to the Rockies 



Islivicola cragini (Gilbert) Cragin's Darter 

 (Poecihchthys cragim (Gilbert) ) 

 Sides almost plain except for very fine dots and mottling; no red or blue 

 coloring; Ind. to Florida 



Claricola squamiceps (Jordan) 

 (Poecihchthys squayniceps (Jordan) ) 



343. Head flattened and depressed behind the eyes 344. 

 Head compressed and elevated behind the eyes 352. 



344. Premaxillaries more or less protractile (protractile downwards, groove 



not evident from above, in E. hlennioides) ; anal fin with one or two 



spines and six to nine rays 345. 



Premaxillaries not protractile (no groove between them and forehead) ; 



anal fin with two spines and ten to twelve rays 349. 



345. With one soft spine in anal fin; usually with eight or nine dorsal spines; 



snout moderately sharp; color usually brownish, often with M or W' 

 shaped lateral markings 346. 



With two spines in anal fin; usually with ten to fourteen dorsal spines; 

 snout blunt; color mostly greenish, with dark lateral bands extending 

 down from a dark dorsal area or with more or less diamond shaped 

 markings 347. 



346. Cheeks scaly; second dorsal fin with fine dark markings; eastern and 



central states to Colorado 



Boleosovia nigrum (Raf .) Johnny Darter 

 Boleosoma nigrum nigrum (Raf.) 

 Cheeks without scales; second dorsal fin with dark bands; east of the 

 AUeghenies southward to N. Carolina 



Boleosoma olmstedi (Storer) Tessellated Darter 

 Boleosoma nigrum olmstedi (Storer) 



299 



