• fins of small native minnow specimens (i.e. distance without spines from front of • pectoral fin anal fin base Asian Carp with 15-18 to base of rays and stiff, caudal fin hard spine going more having a than 2.5 times finely serrated into the posterior distance from (rear) margin anal fin base • dorsal fin forward to tip with moder- of snout) ately stiff, • throat teeth nonserrate fused (See spinelike ray Figure 2-II), at origin molariform • anal fin (C) (i.e. knobs Key To Identification falcate (i.e. looking similar to human molars) hooked) with 12-13 rays Information Sources: Asian carp are large 39-40 in. (40-50 lb.) fish introduced and slightly into the U.S. by fish farmers in Southern states in the stiffened, Etnier, D.A. and W.C. Starne. 1993. The fishes of 1960’s and 70’s to control vegetation and algae blooms. nonserrate Tennessee. University of Tennessee Press, Three of these species, the grass carp (Ctenopharyn- spine at origin Knoxville. 681 pp. godon idella), bighead carp (Hypophthalmichthys • dorsal fin Pflieger, W.L. 1975. The fishes of Missouri. Mis- nobilis), and silver carp (Hypophthalmichthys molitrix) with 8 rays souri Dept. of Conservation, Jefferson City. 343 pp. have been released or have escaped to the wild and are and origin of fin (D) behind pelvic insertion Robison, H.W. and T.M. Buchanan. 1988. Fishes of reproducing in many rivers and streams of the Missis- • a smooth ventral keel (E) extending from base of anal Arkansas. University of Arkansas Press. sippi River Basin. As they continue to expand their fin to isthmus at the base of the gills Fayetteville. 536 pp. range, and show up in commercial and sport fish catches, • gill rakers extremely numerous and fused or covered Smith, P.W. 1979. The fishes of Illinois. University a need has arisen to develop a simple key to assist fishers with a netlike or spongelike porous matrix of Illinois Press. Urbana. 314 pp. and resource managers in making quick and accurate • pharyngeal teeth 4-4, moderately long and bluntly USGS Online. Nonindigenous aquatic species. http:// field identifications. rounded nas.er.usgs.gov/fishes/accounts/ • intestine very long with many loops, its length 3-6 Five species are included in this key. In addition to the times longer than total fish length For more information contact: grass, bighead and silver carps; the common carp (Cyprinus carpio) and the black carp (Mylopharyn- Black carp godon piceus) have also been included. The black carp • thick, elongate body with broad, blunt head is being used extensively by fish farmers, primarily in • golden/dark grey/brown color with scales on back Southern states, to control snails that harbor a trematode and sides showing a prominently dark-edged, giving a parasite that infests catfish and taints their flesh. The characteristic cross-hatched effect (A) black carp is similar in appearance to the grass carp, and • subterminal mouth (B) with thin unspecialized lips the possibility of its escape from captivity is high, so • dorsal fin short and pointed with 7-8 rays and situated resource managers and fishers are urged to be watchful over the for it. The key to Asian carp identification which follows pelvic fins assumes that the reader can readily distinquish the • anal fin common carp from other fish species: closer to caudal fin 1. Dorsal fin rays 13 or more; dorsal and anal fins with a strongly serrated (barbed) anterior (front) than in Revised - 30 April 2004 spine...... Common carp Dorsal fin rays 9 or fewer; dorsal and anal fins • anal fin and strongly lacking strongly serrated spines...... 2 closer to decurved 2. Distance from origin of anal fin to caudal fin base caudal fin anteriorly (C) equal to distance from anal fin origin to pelvic fin than in with 85-100 insertion (Figure 1-I), scales large, carp-like...... 3 native scales Distance from origin of anal fin to caudal fin base minnows • scale rows 1.5 to 2 times distance from anal fin origin to pelvic fin (i.e. distance above lateral insertion (Figure 1-II), scales small, trout-like...... 4 from front of line 26-28 anal fin base to • fins of small base of caudal specimens fin going more without spines than 2.5 times • pectoral fins into the distance with 16-21 rays from anal fin and large base forward to individuals tip of snout) with sharp, • pharyngeal nonserrate Figure 1. Relative anal fin positions of Asian carps. throat teeth 2,4- ridges along 5-4,2 (those in several of the 3. Pharyngeal teeth 2,5-4,2 (located behind the mouth principal row anterior rays Juvenile bighead carp in the throat) with prominent with deep • moderately Juvenile grass carp parallel grooves (Figure 2- parallel grooves stiff I...... Grass carp (See Figure 2-I) nonserrated Pharyngeal teeth molariform spine at dorsal (Figure 2-II)...... Black carp Bighead carp fin origin 4. Ventral keel on abdomen • deep bodied, • anal fin (belly) extends forward only to somewhat falcate (i.e. the base of pelvic fins; gill I. grass carp teeth laterally hooked) (D) rakers long and slender; body compressed with 13-14 soft with scattered dark blotches..... body with back rays ...... bighead carp and upper sides • smooth ventral keel (E) extending from vent forward Ventral keel on abdomen dark gray to pelvic fin base extends forward past pelvic fin grading to off- • gill rakers long, comblike (length 40 times width) and base to isthmus (i.e. base of white on lower sides and belly, many dark to black close-set, not fused into a porous, net-like plate gills): gill rakers forming a II. molariform teeth irregularly shaped blotches scattered over entire body • pharyngeal teeth 4-4, moderately long and bluntly compact mass covered by a • young silver in color, not developing blotches until rounded net-like matrix; body lacking Figure 2. Anterior about 8 weeks of age (see juvenile photo) • intestine long with many loops, its length 3-5 times scattered dark view of pharyangeal • large, scaleless head and opercle longer than the total fish length blotches...... silver carp arches showing teeth • mouth large and terminal (A) without teeth in jaws, configurations of and with lower jaw projecting beyond upper jaw Silver carp Further descriptive details by grass carp and black • eyes situated far forward (B) along midline of body • deep-bodied, laterally compressed body, very silvery species follow: carp-like (i.e. and projecting downward in color in young with back and upper sides changing molariform) teeth. • scales very to olivaceous (greenish), grading to silver below the Grass carp tiny, lateral line in adults • thick, elongate body with broad, blunt head cycloid, • scales very tiny and cycloid, resembling those of trout • silver/pale grey color with scales on back and sides resembling • head and opercle scaleless with relatively large, showing a prominently dark-edge, giving a characteris- those of upturned mouth (A) without teeth in jaws tic cross-hatched effect (A) trout • eyes situated far forward (B) along the midline of the • subterminal mouth (B) with thin unspecialized lips • lateral line body and projecting somewhat downward • dorsal fin short and pointed with 7-8 rays and situated complete • lateral line scales approximately 95-103 over the pelvic fins