A Morphological Comparison of the Adults of Oryzaephilus surinamensis (L.) and O. mercator (Fauv.) (Col., Cucujidae).

Abstract

The object of the work described in this paper was to compare adults of Oryzaephilus surinamensis (L.) and O. mercator (Fauv.) by morphological and biometric methods with a view to determining the status of the latter as either a variety of O. surinamensis or as a separate species.There are some marked and constant differences between the two insects in the structure of the male genitalia. These are listed.The analysis of the biometric results shows a clear-cut difference between the two insects in the ratio of eye length to temple length. All the other ratios considered overlap, although the means may be widely different. Some of these ratios are illustrated by histograms.A cross-breeding experiment gave no offspring from the mixed pairs.It is concluded that O. mercator is a good species which can be recognised morphologically.