Morphometric Studies of the Sweet Potato Weevil, Cylas Species- Complex in Southern Ghana

  • Maxwell K. Billah University of Ghana
Keywords: Sweet potato, morphometric studies


The Sweet potato weevil, Cylas species, is a key pest of sweet potato, and widely distributed on the African
continent. The management of the pest is limited because its taxonomic status is not clear. Populations of the
same species occupying distinct localities experience different ecological and climatic pressures that might
result in differentiation in traits. This study sought to identify and compare body sizes of Cylas species from
four regions in southern Ghana – Central, Eastern, Greater Accra and Volta. Of the 6,686 samples collected from
the four regions, two species were identified: Cylas brunneus Fabricius, and Cylas puncticollis Boheman. Twelve
morphometric characters were examined and measured, of which four traits - elytra and rostrum lengths,
pronotum and head widths contributed most to the variations observed. In C. puncticollis, individuals with the
longest body were recorded in Greater Accra Region (7.084 ± 0.089 mm), while those in the Central Region had
the smallest body size (6.786 ± 0.086 mm). Our findings suggest that distinct localities may influence changes
in body size.

Author Biography

Maxwell K. Billah, University of Ghana

African Regional Postgraduate Program in Insect Science (ARPPIS), University of Ghana, Accra, Ghana

Department of Animal Biology and Conservation Science (DABCS), University of Ghana, Accra, Ghana