9327

• UCREFRP Catalog Number: 9327
• Author: Starnes, W. C.
• USFW Year: 1995.
• Copyright Material: NO

along with partitioning or removing some upper basin samples by
morphology, had the interesting effect of allowing the Moapa and
Virgin river samples to cluster with the Chevelon and Pahranagat
samples paired with a large grouping containing all Gila and Bill
Williams samples and the Guzman Basin sample. In prior analyses
(Figs. 13,14), the Williamson Valley-Guzman Basin samples, which
consistently paired through all analyses as previously noted,
clustered outside the Chevelon-Pahranagat pair, which in turn,
clustered outside all other Gila Basin-Bill Williams samples;
however, in clustering Chevelon-Pahranagat with the Moapa-Virgin
pair, this relationship was juxtaposed (Fig. 15). Within the
large subgrouping containing all Gila Basin and Bill Williams
samples exclusive of Williamson Valley (i.e., SHY thru CNG, Fig.
15), relative positions of samples in clusters did not change
with this reconfiguration of the data set. Eliminating selected
samples from subsequent UPGMA analyses (Figs. 16,17) caused some
realignments among the main grouping of Gila Basin samples but
groupings (e.g., FRN, EFK, etc.; BAB, SAB, etc.) set apart by
lesser similarity to the main-grouping remained intact.
The UPGMA result depicted in Figure 15 is inclusive of the
greatest number of samples from the lower Colorado Basin after
deleting the small Agua Fria (n=2) sample of any BIOSYS run.
Before proceeding with observations on patterns in results of
that analysis, it should be noted that UPGMA and other phenetic
analyses conducted by DeMarais (1992) clustered his Sycamore
Creek (=Agua Fria herein) sample (size not given but presumably
much more than 2) well within a grouping of other samples from
the Gila Basin (paired with his East Verde R. sample). The
aberrant external placement assigned to the small Agua Fria
sample herein (Fig. 13) is explained by the presence of alleles
at several loci that were scored in no other samples of the
entire study; there is a possibility that tissues in this tiny
sample were transposed with those of the cyprinid Agosia or the
catostomid Catostomus and it will not be considered further in
discussion.
In Figure 15, several samples do not group with respect to
geographical proximity or morphology within the main Gila Basin
grouping (VDP thru VDS). Two pairings within that grouping,
Tonto + Cherry, Verde R. at Tapco + West Clear creeks actually
reflect both proximity and morphology, though the first is set
off from several others by nuances. External to that main
grouping, the cluster SHY - SYC contains both Bill Williams
system samples (Francis, Sycamore crs.) but also contains the
geographically remote East Fork Gila sample from the headwaters
of the Gila Basin in New Mexico and the Sheehy Spring sample from
the extreme southern (upper) Santa Cruz portion of that basin. A
somewhat more intuitive, from both the standpoints of geography
and morphology, grouping occurs external to that, the BAS + SAB +
CNG cluster which represents morphologically relatively similar
populations (e.g., Douglas, herewith) from the southern San Pedro
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