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Meristic characters considered important were counts of precaudal vertebrae and gill rakers of the second arch (Smith et al. 1979, Figure 16) Sixteen of the 19 Green River Gila specimens had precaudal vertebrae counts in the G. cypha, G. robusta range; three had precaudal vertebrae counts in the G.' elegans range. Nine specimens had gill raker counts in the G.' robusta range; eight were in the G. cypha range and two in the G. elegans range (Figure 16). Taxonomic analysis is continuing for Gila spp. More information will be provided in subsequent reports and publications. Razorback sucker' Five razorback suckers were collected from the Yampa and Green rivers during 1981 (Table 24). Only one razorback (Green River, RM 344.3, 5/17/81) was captured during standardized sampling. Four fish including one recapture, were collected from a riffle in the Yampa River at 0.3 mi (0.5 km) upstream from its confluence with the Green river (Echo Park). Fish No. 1342 was a ripe female that was originally tagged by Bio/West, Inc. in March, 1978. near Island Park, approximately 12 mi (20 km) downstream from the recapture point. The other three fish were ripe tuberculated males. Two of the males were collected (and several other individuals seen, but not captured) at the upper end of a gravel/rubble bar in shallow (less than 1.0 ft; 0.3 m) relatively swift (greater than 1.2 ft/s) water. The female and remaining male were collected from a sand/silt shoreline near the lower end of the same bar in slower current (less than 0.5 ft/s). McAda and Wydoski (1980) found several razorback sucker in spawning condition on this same riffle in 1975. Collections of only five individuals in 1981 precludes-'any intensive analysis of the abundance or distribution of razorback sucker in the' Yampa and upper Green rivers. In CRFP studies on 300 mi of the Green River below Split Mountain (Tyus et al. 1981), only 92 individuals were collected in three years (1979-1981) of sampling. Only five of the 92 were collected during the standardized sampling program. Only adults were collected indicating low or nonexistent reproductive success in recent years. Collections of adults in the lower Yampa in 1981 in spawning condition strongly suggest spawning activity, however, succes's of this attempt is suspect since no young were subsequently collected. 72