Graduate Thesis Or Dissertation

Taxonomic analyses of the Oregon chub, Oregonichthys crameri

Public Deposited

Downloadable Content

Download PDF


Attribute NameValues
  • The Oregon chub. Oregonichthys crameri. one of Oregon's endemic freshwater fishes. is restricted to the Willamette and Umpqua rivers and their tributaries. Specimens from the two rivers have traditionally been considered the same species. The goal of this study was to re-examine that assumption and determine if the Willamette Oregon chub and the Umpqua Oregon chub represent different taxa. The Oregon chub were examined through three sets of data: meristic. morphometric. and electrophoretic. Univariate (General Linear Model) and multivariate (Principal Components Analysis and Discriminant Function Analysis) analyses were performed. Univariate analyses resulted in significant differences between the Willamette and the Umpqua in the meristic characters: precaudal vertebrae. caudal vertebrae. the difference between precaudal and caudal vertebrae. pelvic fin rays, rudimentary dorsal rays, total dorsal rays, upper procurrent caudal rays, total caudal rays, maxillary barbels, and cephalic lateral line counts; in the morphometric characters: body width, head depth, eye length, and anal base length; and in the electrophoretic character, lactate dehydrogenase in muscle tissue. Discriminant function analysis based on meristic characters correctly classifies 90% of the Willamette and 65% of the Umpqua specimens. Discriminant function analysis based on morphometric characters correctly classifies over 89% of the Willamette and over 84% of the Umpqua specimens. Descriptions of the Willamette and Umpqua Oregon chub subspecies are given.
Resource Type
Date Available
Date Issued
Degree Level
Degree Name
Degree Field
Degree Grantor
Commencement Year
Academic Affiliation
Non-Academic Affiliation
Rights Statement
Peer Reviewed
Digitization Specifications
  • File scanned at 300 ppi (Monochrome, 8-bit Grayscale) using ScandAll PRO 1.8.1 on a Fi-6770A in PDF format. CVista PdfCompressor 5.0 was used for pdf compression and textual OCR.



This work has no parents.

In Collection: