The Flagfin Shiner, Notropis signipinnisBy Dick Stober
reprinted from American Currents, Fall 1973
Note: Species now known as Pteronotropis signipinnis
Notropis signipinnis, also called the flagfin shiner, is a beautiful native American fish of our southeastern states. This beauty shows a preference for small, clear, spring-fed streams and narrow, rather deep channels, widening out at times into pools or briskly cascading over rocky ledges. Shade or bright sunlight, it doesn't seem to matter to the frolicking flagfin. Schools of twenty to thirty may be seen feeding near the surface in pools and eddies and around bridges or culverts where they can easily be collected with a small seine or dip net.
It's a real treat to sit on a warm rock in the bright sunlight under an icy blue sky, looking at a bagful of beautiful flagfins. It is obvious where this name comes from since they fly the national colors of Spain. The pectoral and pelvic fins are predominately yellow. The dorsal, anal and caudal fins are yellow close to the body, warming to a brilliant reddish orange toward the extremities. The rays of the dorsal as well as the anterior rays of the anal are bordered by black except at the top and bottom in the vicinity of the caudal spot. The base color of the body is pearly. A rose-violet iridescent lateral band passes from the tail through the upper part of the eye to the snout. Below this color band is a wider black band. The body coloration is very similar to the African Pelvicachromis pulcher. Without going into too much detail it would probably suffice to say that the body shape of signipinnis differs from that of most species of Notropis in that the body is broader in the vertical plane rather than the usual oblong shiner shape. Most reference books claim that the average length of signipinnis is two inches, but we grow them big here in Alabama with males averaging closer to three inches from the snout to the base of the caudal fin. Breeding males display nuptial tubercles on the chin, lower jaws and on the side of the head. Females are without tubercles.
In general appearance the male has a broader lateral band of black with more intense coloration than the female (which is otherwise quite similarly colored). After careful inspection this difference becomes obvious, but at first glance differentiation of the sexes is difficult. The flagfin is a congenial community tank member with an easy to please appetite, it loves flake food and feels right at home swimming in the effluent of a power filter. You can watch them darting in and out during feeding time, eating the food drawn into the water by the current.
If you would place three females and two males in a twenty gallon, clean, well-planted aquarium with soft acid (pH range 6.5 to 7.0) water it should be just a matter of time that you will see fry swimming on the surface among the plants. It goes without saying that the adult fish must be healthy and well conditioned. Upon close examination you might see eggs scattered at random throughout the tank. The eggs appear to be semi-adhesive with some sticking to the plants and others scattered over the bottom among the gravel. As close as I can determine the hatching period is approximately 72 hours. The parents do not appear to make a concerted effort to seek out the fry, however, they manage to keep the number thinned down so that there is never a problem of over population. It's an easy task to remove newly hatched fry from the surface with a drinking glass. It has been my experience that fry do best when their normal diet is supplemented with frequent feedings of green water.
The Notropis signipitinis is classified as a forage fish which means that besides being a beautiful addition to our home aquarium it is a member of a group of fish which are an important link in the food chain of our southern streams. We must all exert every effort to preserve this fish by protecting it and its' natural habitat.
A closely related shiner is N. hypselopterus, the sailfin shiner, illustrated in
Innes' Exotic Aquarium Fishes and in Axelrod et al.'s Exotic Tropical Fishes (F-446.00).
Used with permission. Article copyright retained by author.