156 NORTHERN FISHES 



Mississippi drainage in Minnesota and Wisconsin. Greene (1935) re- 

 ported it in central and southern Wisconsin. He believes this species 

 to be in process of extirpation in Wisconsin liecause of its widely scat- 

 tered distribution, and also reports numerous cases of hybridization 

 with other minnows. 



GENUS Opsopoeodus Hay 



PUGNOSE MINNOW 

 Opsopoeodus emiliae Hay 



The pugnose minnow has a slender body and a short head with a 

 small, upturned mouth. The back is yellowish; the sides are silvery, 

 with dark lateral stripes. There is a black spot on the back of the dorsal 

 fin. The dorsal fin has 7 to 10 rays, the anal fin 8. The scales are 5-40-3. 

 The pharyngeal teeth are 5 — 5 or 4 — 5, with serrated edges. This 

 species reaches a length of over 4 inches. 



The pugnose minnow ranges from southern Minnesota to the west- 

 ern end of Lake Erie and southward to Florida and Texas. Greene 

 (1935) reported it from the Lower Mississippi River and from else- 

 where in southern Wisconsin. There are no specimens from Minnesota 

 in the University of Minnesota collections. 



GENUS Notemigonus Rafinesque 



WESTERN GOLDEN SHINER (Bream, Roach) 

 Notemigonus crysoleucas auratus (Rafinesque) 



The western golden shiner (Figure 25C) is a deep-bodied minnow 

 with a large eye. The back is greenish, and the sides are pale with a 

 golden tinge. The lateral line is curved downward. There are about 

 51 scales in the lateral line. The teeth are 5 — 5. This species commonly 

 ranges up to 5 inches in length, but occasionally up to 12 inches. 



The western golden shiner is distributed from North Dakota to 

 southern Ontario and southward to Oklahoma and the Ohio Valley. 

 Greene (1935) reported it from all parts of Wisconsin. In Minnesota 

 golden shiners are more common in lakes than in streams. They prefer 

 shallow lakes and ponds. Golden shiners are the only fish that survive 

 in some ponds and sloughs where the oxygen is completely exhausted in 

 winter. Laboratory experiments at the University of Minnesota indicate 

 that at freezing temperatures this fish can live with very little oxygen 

 but at higher temperatures requires as much oxygen as any other fish. 



GENUS Notropis Rafinesque 



This genus contains a large number of species, which are widely 

 spread. At least seventeen species are reported from Minnesota. 



