The Herpetological Journal

pp.93-96

Authors: T. Clifford

Abstract: Adult female Triturus vulgaris breeding at seven small ponds within a freshwater marsh at Saltfleetby-Theddlethorpe Dunes National Nature Reserve were measured, weighed and examined for throat and belly spotting.

When the data were combined it was found that 26. 8 percent ± 4.2 per cent S. E. of the total population had immaculate throats. Immaculate-throated newts tended to have fewer, smaller and usually less distinct belly spots than the normal spotted-throated form. All the immaculate-throated newts in the sample were found to have dark-yellowish throat and lower mandible pigmentation.

There were no significant morphometric differences between immaculate-throated and spotted-throated newts at the study site although the immaculate-throated animals were found to have a significantly shorter head + body length than those recorded in mid Wales by Harrison, Gittins and Slater (1981). Both immaculate-throated and spotted-throated newts at the study site were found to be significantly lighter than those recorded by Frazer ( i 983) and Harrison et al. ( 1 981 ).

It is suggested that the high incidence of immaculate-throated female smooth newts at Saltfleetby-Theddlethorpe Dunes NNR is the result of the 'founder effect'.