7259

• UCREFRP Catalog Number: 7259
• Author: Rosenfeld, M. J.
• Title: Preliminary Electrophoretic Study of the Colorado River Chub ‎(Pisces
• USFW Year: 1986.
• USFW - Doc Type: Cyprinidae, Genus
• Copyright Material: NO

not prospects for future screenings since samples would be

hard to gather without severe tr~uma or death.

This preliminary electrophoretic study does show that at least

larval and juvenile fishes might be identified as belonging to

either a roundtail or bony tail-humpback lineage or to a hybrid

state between them, using protein electrophoresis.

Young-of-year

sampling typically involves th~ fixation and preservation of

specimens intended for morphological examination.

A larval or

juv~nile sUb-sample preserved ~n dry ice would be required; the

entire animal would be macerated to obtain the requisite liver

proteins.

Electrophoresis of liver proteins indicated that the current

concept of phylogenetic relationships may be incorrect. The

roundtail chub may not be allied closely to either the bonyt~il

or humpback chubs, yet the bony tail chub has been considered a

sub3pecies of the roundtail chub (Ellis, 1914; Uyeno, 19(0).

Phenetic clusterings indicated greater similarities between the

roundtail chub and the Utah chub as well as the tui chub than

between the roundtail chub and either the humpback or bony tail

chubs.

Sample sizes were relatively small as well as not

necessarily representative of populations throughout the Upper

Colorado River, yet the genetic dist2nce separating the "round-

tail" chub from its Colorado River congeners is so great that the

g~netic distinctness of the "roundt21il" chub is likely real and

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