7022

• UCREFRP Catalog Number: 7022
• Author: Mayden, R. L., W. J. Rainboth and D. G. Buth
• Title: Phylogenetic Systematics of the Cyprinid Genera
• USFW Year: 1991
• Copyright Material: YES

?(] BROWN-SCULP
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DEPARTMENT OF WILDLIFE AND FISHERIES
BIOLOGY,`UNIVERSITY OF CALIFORNIA, DAVIs,
CALIFORNIA 95616. Accepted 25 July 1990.
Phylogenetic Systematics of the Cyprinid Genera. Mylopharodon
and Ptychocheilus: Comparative Morphometry
RICHARD L. MAYDEN, WALTER J. RAINBOTH, AND
DONALD G. BUTH
phylogenetic relationships among the western North American cyprinids My-
lopharodon conocephalus and the four species of Ptychocheilus--P- grand
Lucius, P, oregonensis, and P. umpqua-were estimated from the perspective of
an outgroup species, He*eroleucus symmetricus. Canonical vanate analysis (CVA)
of 46 morphometric measures yielded scores that had group blvarlate prediction
ellipses with minimal overlap among species (95% prediction interval). These
measures also indicated large phenetic differences between A lucius and M.
conocepWus, and other ingroup taxa. Ptychocheilus umpquae from the Umpqua
and Siuslaw drainages was easily separable and may warrant recognition as
separate taxa. Gap-coding of six counts and 35 measures yielded multistate char-
acters that were then subjected to parsimony analysis. This analysis yielded a
single tree with a consistency index of 0.868, with most of the homoplasy as-
sociated with A lucius. The Wagner analysis supported the monophyly of the
genus Ptychocheilus and the relationships within the genus of (oregonensis [umpquae
(grandis, lucius)ll consistent with a north-to-south pattern of speclation. Given
the ages of fossil taxa in the genus and their hypothesized relationships to extant
members, the genus evolved prior to the Miocene. No taxonomic changes have
been proposed for this group at this time, although additional study of the
population currently recognized as P. umpquae inhabiting the Siuslaw drainage
is warranted. A key to the species of Ptychocheilus has been provided.
QUAW FISHES of the genus Ptychocheilus in-
S clude the largest native members of the
North American cyprinid assemblage, with P.
lucius reputed to reach a length of 150 cm and
a weight of 45 kg (Moore, 1968; Minckley, 1973;
Holden, 1980). Four extant species are recog-
nized, all distributed in western North America
(Fig. 1). Ptychocheilus oregonensis (Richardson)

0 1991 by the American Society of Ichthyologists and Herpetologists