Name:
|
- Semotilus, from the Greek, sema, "banner";
and the second part meant to mean "spotted"
- margarita, from the Greek, "pearl"
- Common name
- Other common names include: Nachtrieb Dace, Northern Dace, Northern
Pearl Dace, Northern Minnow
|
Taxonomy:
|
- Kingdom Animalia
- Phylum Chordata, animals with a spinal chord
- Subphylum Vertebrata, animals with a backbone
- Superclass Osteichthyes, bony fishes
- Class Actinopterygii, ray-finned and spiny rayed fishes
- Subclass Neopterygii
- Infraclass Teleostei
- Superorder Ostariophysi
- Order Cypriniformes, minnows and suckers
- Family Cyprinidae, carps and minnows
- Genus Semotilus, the creek chubs
- Minnesota Pearl Dace are of the subspecies Semotilus margarita nachtriebi,
named after Professor Henry Nachtrieb, of the University of Minnesota and
former director of the Minnesota Zoological Survey.
- Also known as Margariscus margarita
|
Description:
|
- A stout-bodied, cold water minnow.
- Length up to 6", 3"-4" average
- Coloration
- dusky mottled on the upper sides (many of the scale pockets on the sides
are darkened, giving the mottled appearance)
- silver grey to white on the lower sides
- white belly
- usually a dark spot near the base of the tail
- dark lateral band is distinct on the young, but fades in adults
- adult males have orange-red sides below the lateral band
- females may also show some color during spawning
- Body
- elongated form, nearly cylindrical in cross section
- usually complete lateral line of 62-78 scales
- dorsal, anal, and pelvic fins of 8 rays
- pectoral fins of 15/16 rays
- Head
- mouth terminal, nearly horizontal with the upper jaw, separated from the
snout by a groove
- small barbel in the groove of the upper jaw (occasionally lacking)
- hooked pharyngeal teeth in a 2, 5-4, 2 pattern, but count is variable.
- During the breeding season, males have a pink to red-tinted stripe along
their lower sides, and the upper sides of the pectoral fins bear paired
rows of small, sharp tubercles.
|
Identification:
|
|
Distribution:
|
- Native range centered in the northern Great Lakes states with extensions
from Nebraska into New Foundland; scattered populations in central Canada
- A relict or remnant population is found in parts of South Dakota, Nebraska
and northern lowa.
|
Habitat:
|
- Cool bogs, ponds, lakes, creeks, and clear streams.
- Cool, boggy waters of lakes and ponds and in the cold headwater streams
often associated with trout.
|
Associates:
|
- Feeds on algae, aquatic insects, free-floating animal plankton, and a variety
of other small aquatic organisms.
- A forage fish for larger sport fishes in some waters.
|
History:
|
- State Endangered in Iowa.
- State Threatened in South Dakota
|
Uses:
|
|
Reproduction:
|
- Spawns in late spring to early summer, in clear water with a weak to moderate
current, over sand or gravel.
- No nest is built, but the small spawning area is guarded by the male.
|
Comments:
|
|
Links:
|
|
|
Last updated on 15 October 1999
|
