Data collected from the 16 species of the fish family
Cyprinidae (Pisces: Teleosti) found in Britain were
examined morphometrically and electrophoretically to examine
the taxonomic relationships within the group and aspects of
the occurrence and identification of interspecies hybrids.
The analysis of morphological characters by Principal
Components Analysis was not able to separate the morphological
characters into clear character suites. A rooted dendrogram
using Gower (1971) mixed data coefficient and UPGMA was found
not to correlate strongly with the presently accepted
classification or with the subsequently produced phenogram
based upon the enzymatic results. The phenetic treatment of
electrophoretic results gave a consensus topology equivalent
to Nei's (1972) .D. and UPGMA with standard errors.
Several taxonomic changes were suggested, the reduction from
six to two sub-families and moving two species into different
genera, Blicca bjoerkna to become Abramis bjoerkna and
Alburnus alburnus to become Leuciscus leuciscus.
The use of electrophoretic characters in preference to
morphological ones was strongly validated. Discriminant
Function Analysis could not discriminate between populations
with and those without hybrids.
An unidentified specimen from the River Trent, Nottingham, was
also described. It was found enzymatically not to correspond
to any of the 16 species examined, but could be placed in the
classification in the sub-family Leuciscinae and Abramin
A Doctoral Thesis. Submitted in partial fulfilment of the requirements for the award of Doctor of Philosophy of Loughborough University.