7601

• UCREFRP Catalog Number: 7601
• Author: Minckley, W. L.
• Title: Native Fishes of Arid Lands
• USFW Year: 1991.
• USFW - Doc Type: A Dwindling Resource of the Desert Southwest.
• Copyright Material: NO

Figure 31. Speckled dacelpecesito moteado from three
Arizona localities: Upper: Aravaipa Creek, 67 mm in total
length; Middle: Beaver Dam Wash (Virgin River drainage),
71 mm; and Lower: Pari a River canyon, 70 mm long.

notoriously turbid, and floods violently through a
narrow gorge (Fig. 32); persisting in such a place
must require a unique body shape, plus remarkable
adaptations at levels other than reflected in
morphology.
Speckled dace in some other tributaries, including
those lower in the system, are far less spectacular.
Many are small and round-bodied, with reduced fins
and relatively large, loosely overlapping scales. They
live in quiet pools as well as riffles of creeks.
Speckled dace are opportunistic carnivores, feeding
heavily on aquatic insects and other invertebrates,
and only occasionally on plant materials.
The longfin dace (Fig. 33), shared by the Colorado
and Rio Yaqui systems, occurs from uplands to

Figure 32. Paria River in Pari a Canyon, Arizona. Photograpl
by G. C. Kobetich.

Figure 33. Longfin dacelchara/ito a/eta larga, 86 mm in total
length, from Aravaipa Creek, Arizona. This minnow, unlike
most western fishes, remains relatively abundant through
much of its original range. It disperses rapidly from isolated
refuges when intermittent desert washes begin to flow after
rains, and was thought by early settlers to emerge from the
sand.

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