D.A. Neely | Geology Reports

USGS2019

Characteristics for the external identification of Black Carp from Grass Carp

Black Carp Mylopharyngodon piceus and Grass Carp Ctenopharyngodon idella are morphologically similar species native to eastern Asia and imported to North America as biological control organisms. Preferred identification methods are coloration and pharyngeal tooth form. Grass Carp possess serrated teeth and Black Carp molariform teeth. Examination of pharyngeal teeth causes extensive damage to a specimen and is labor and time intensive. Coloration can vary within a species and fades with preservation. We present a suite of external characteristics consisting of a truss network canonical variate analysis of distance measurements among landmarks on the lateral view of the head of each fish, the ratio of head length to mouth width, the visible presence of the premaxilla viewed dorsally with the mouth fully closed, and anterior lateral line angles among scales. Canonical variate analysis suggested that Grass Carp have a deeper head at the preoperculum and Black Carp a more elongate head relative to the preoperculum and eye. Comparisons of head length to mouth width ratio, visibility of the premaxilla dorsally with the mouth fully closed, and anterior lateral line angles all served as external characteristics of species, but outliers were present for each method. Because of the plastic morphology of wild populations, we suggest that a combination of characters be applied for identification.

Journal of Fish and Wildlife Management↗

USGS2007

Three new percid fishes (Percidae: Percina) from the Mobile Basin drainage of Alabama, Georgia, and Tennessee

Three new species of Percina are described from upland drainages of the Mobile Basin. Two of the three species are narrowly distributed: P. kusha , the Bridled Darter, is currently known only from the Conasauga River drainage in Georgia and Tennessee and Etowah River drainage in Georgia, both tributaries of the Coosa River, and P. sipsi , the Bankhead Darter, which is restricted to tributaries of Sipsey Fork of the Black Warrior River in northwestern Alabama. The third species, P. smithvanizi , the Muscadine Darter, occurs above the Fall Line in the Tallapoosa River drainage in eastern Alabama and western Georgia. In a molecular analysis using mitochondrial cytochrome b sequence data, P. kusha and P. smithvanizi were recovered as sister species, while Percina sipsi was recovered in a clade consisting of P. aurolineata ( P. sciera + P. sipsi ). Two of the three species, P. kusha and P. sipsi , are considered to be imperiled species and are in need of conservation actions to prevent their extinction. Description of these three darters increases the number of described species of Percina to 44. Sixteen are known to occur in the Mobile Basin, including nine that are endemic.

Alabama, Georgia, Tennessee↗