NOTROPIS ALBIZONATUS, A NEW CYPRINID FISH ENDEMIC TO THE TENNESSEE AND CUMBERLAND RIVER DRAINAGES, WITH A PHYLOGENY OF THE NOTROPIS PROCNE SPECIES GROUP

Notropis albizonatus, n. sp., an endemic to the Tennessee and Cumberla nd river drainages, Kentucky, Tennessee, and Alabama, differs from oth er members of the Notropis procne species group in having a broad, dep igmented supralateral stripe bordered ventrally by a dark midlateral s tripe of equal intensity; predorsal stripe obsolescent or wanting, no postdorsal stripe; snout tubercles absent; lateral-line scales 36-38; predorsal scale rows 16-17; and unique genotypes for the Pgm-A locus. Only two disjunct populations of N. albizonatus persist, placing it am ong the most endangered fishes in North America. The species occurs in the Little South Fork (Cumberland River drainage, Kentucky) and Paint Rock River (Tennessee River drainage, Alabama) where it is an inhabit ant of clear, clean pools and runs over rock bottoms. These two system s are being altered by toxic runoff, channelization, and siltation. Th e species was recently listed as federally endangered. Using the princ iple of parsimony, we optimized allelic frequencies for 37 presumptive loci on 945 possible unrooted trees for seven species: Notropis albor us, N. albizonatus, N. chihuahua, N. greenei, N. ludibundus, N. procne , and N. uranoscopus. We tested hypothesized sister relationships of N . albizonatus and estimated relationships in the N. procne species gro up. Notropis albizonatus and N. procne, formerly hypothesized as siste r species, exhibit complete genotypic differentiation at three loci, P ep-S, Pgm-A, and Pgdh-A, and are not supported as sister species. Root ing the shortest network (L = 76.38) to either N. alborus or N. greene i, N. albizonatus, N. chihuahua, N. ludibundus, N. procne, and N. uran oscopus comprise a monophyletic assemblage. Notropis albizonatus is th e sister species to a N. chihuahua-N. uranoscopus clade, and N. ludibu ndas-N. procne are sister species, comprising the sister group to the N. albizonatus clade.