Biochemical and molecular species identification techniques have a broad ra
nge of applications in the management and conservation of marine organisms.
While species boundaries are not always clearly defined, phylogeneticists
utilise autapomorphic characters to distinguish phylogenetic species. Genet
ic markers discriminate between marine taxa when traditional morphological
distinctions are unclear. The applications of these techniques can be divid
ed into four general categories. Firstly, compliance enforcement, which oft
en depends on genetic identification techniques to enable officials to iden
tify the species to which regulations pertain. Secondly, quality control ap
plications, to allow for the testing of marine products to guard against fr
audulent substitution with less valuable species, which is particularly per
tinent since processing often obliterates identifiable features. Thirdly, a
variety of applications to ecological and life-history studies and conserv
ation management are reported. Here, the genetic identification techniques
of species from cryptic life-cycle stages or of morphologically indistinct
species are an indispensable tool for marine scientists, conservators and m
anagers. Lastly, the application of genetic techniques for sourcing populat
ion origin is briefly discussed. The biochemical and molecular techniques a
pplied to species identification all exploit phenotypic or genotypic polymo
rphisms that are sampled using either tertiary level protein based methods
or primary level DNA based methods. In this review, examples of the applica
tions along with the total protein, allozyme, serological, PCR and other DN
A based methodologies are briefly described and some generalities with rega
rd to their use are presented.