| Virginia
Journal of Science.
2000. Vol 51 (1) : 17-22 |
| Comparison
of Larval Myomere Counts Among Species of Nocomis in Virginia
(Actinopterygii: Cyprinidae) Terre D. Green and Eugene G. Maurakis, Science Museum, of Virginia, 2500 West Broad Street, Richmond, VA 23220, and Department of Biology, University of Richmond, Richmond, VA 23173 ABSTRACT
Larval myomere counts of Nocomis
platyrhynchus were made using a dissecting light microscope
equipped with polarizing filters, and then compared to those of the
three other species of Nocomis
(Nocomis leptocephalus, Nocomis micropogon, and Nocomis raneyi) found in
Virginia. Average preanal myomere counts for N. platyrhynchus (26.9) were
significantly different from those of the other three species (N. raneyi =28.7; N. micropogon =26.0; and N. leptocephalus =25.9). This
is especially important as larvae of N.
leptocephalus, the only other species of Nocomis syntopic with N. platyrhynchus in the upper New
River drainage, can now be distinguished from those of N. platyrhynchus.
Larvae of N. raneyi also can
be distinguished from those of other species of Nocomis in Virginia based on
preanal myomere counts. However, larvae of N. platyrhynchus and N. raneyi cannot be distinguished
from each other based on total myomeres (42.0 versus 41.7).
Larvae of N. platyrhynchus
can be distinguished from those of three of its nest associates (Lythrurus ardens, Notropis rubellus, and Phoxinus oreas), but not from Campostoma anomalum and Luxilus chrysocephalus using
myomere counts. |