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4 Foreign Nonindigenous Carps and Minnows (Cyprinidae) in the U.S.-A Guide to their Identification Reporting Discovery of Nonindigenous Species The collection of any nonindigenous cyprinid should be reported to state game and fish agencies and to the Nonindigenous Aquatic Species database (http://nas. er.usgs.gov; appendix C). For those wishing to report a new record, be aware that positive identification is of the utmost importance. Consequently, we urge that the specimen be retained if possible or at least well docu- mented with photographs. It is especially helpful for photographic images to be well-focused and to include shots of the entire fish from various angles as well as close-up views of the head and fins. Methods Taxonomy Scientific names and authorities were taken from "A Catalog of the Species of Fishes" (Eschmeyer and others, 1998, and amendments) available through the California Academy of Science (online at: http:// www.calacademy.orglresearchlichthyologylcatalogl fishcatsearch.html). Common names of fishes follow Nelson and others (2004). Meristic and Morphometric Measures Methods of recording meristic (count) and morpho- metric (measurement) data were standardized by Hubbs and Lagler (1958) and reviewed in Strauss and Bond (1990). Additionally, several publications that provide information on fishes of particular regions or states list useful details regarding identification, including standard formats for expressing meristics and morpho- metries (for example, Page and Burr, 1991; Etnier and Starnes, 1993; Jenkins and Burkhead, 1994; Ross, 2001; Boschung and Mayden, 2004). Meristic characteristics are variable within and among the cyprinids treated in this guide. Thus, meristic data from a number of sources are included for each species, including data from both native and introduced populations when available (appendix B). These data were reproduced as given by the original authors. Although most of the original reports follow the standards of Hubbs and Lagler (1958) and Strauss and Bond (1990), some did not (especially those in foreign publications) and, therefore, inconsisten- cies may exist. For detailed information on methods of data reporting, the cited authority should be consulted. Fin-ray counts, comprised of unbranched and branched rays, are often useful in the diagnosis of fish species. When reporting fin-ray counts, the first set of Roman numbers represents the number of soft unbranched rays. The second set (in parentheses) repre- sents the number of soft branched rays. For example, a fin with three unbranched rays and eight branched rays would be represented as: iii (8). The spine-like ray pres- ent in the dorsal and anal fins of some foreign cyprinids (for example, Common Carp, Goldfish, Crucian Carp) and a few native fishes is counted as an unbranched ray. Because the unbranched rays of the dorsal and anal fins are often difficult to discern, most North American fish books report only a single number representing a single unbranched ray plus all the branched rays. The last two branched rays usually share a common basal skeletal element and are counted as one. Counts of gill rakers are based on the first (outer) gill arch and normally performed using the outer arch on the left side of fish. Gill rakers are often aligned in two rows on each gill arch, an outer row of longer rakers and an inner row of short stubs. Only rakers on the outer row are counted, including the smallest in the outer-row series at top and bottom of the arch (Calliet and others, 1986). Some authors give either upper and lower limb counts, or inner and outer (anterior and posterior) counts, and those data are listed in this guide. Length of fishes is conventionally given in either standard (SL) or total length (TL). Standard length is the straight-line distance from the tip of the snout to the posterior end of the vertebral column. The end of the vertebral column can be located by laterally flexing the caudal fin at its base. The crease in the flesh at the base of the caudal fin marks the end of the vertebral column (hypural plate) and the beginning of the caudal fin. Total length is the straight-line distance from the tip of the snout to the posterior tip of the longest caudal-fin rays. North Americans typically measure total length (TL) with the caudal fins compressed dorso-ventrally, resulting in a measure slightly longer than if the caudal fins are left in their natural position (Anderson and Neumann, 1996). Unfortunately, many authors do not report the method used to determine total length. Pharyngeal Teeth Cyprinids do not have jaw teeth. Instead, they rely on their pharyngeal teeth and masticatory pads to crush or process their food. The number, size, and shape of the pharyngeal teeth are generally species specific.