Morphological variations in Nigerian Apis mellifera Linnaeus, 1758 populations in Guinea savannah agro-ecological zone

Apis mellifera Linnaeus, 1758 is one of the most economically valuable insects which plays significant role in human medicine, nutrition and crop pollination. The morphometric variations of honeybee from different locations of the southern guinea and northern guinea savannah ecological zone of Nigeria were studied. Fifteen morphological traits were measured for variation on six hundred (600) worker honeybee samples purposively collected from ten different locations within the ecological zone. Data collected were subjected to one-way Analysis of Variance (ANOVA), SNK test (α=0.05) and Pearson correlation between morphometric characters were determined. At the same time a dendrogram of morphological proximity based on the fifteen morphological features was constructed. Results showed that morphometry variation (p<0.05) existed within the honeybee population in the guinea savannah agro-ecological zone of Nigeria, high morphological similarities were observed in the tibia length of the hind leg and the thorax length. The honeybee samples were classified into two distinct morphoclusters (A and B). Honeybee samples within morphocluster A were closely related in terms of the examined morphometric features and geographic distance (CV=1.65). In contrast, within cluster B, honeybee samples were closely related despite the vast geographical distance (CV=3.30, p<0.05). The body length was significantly positively correlated with the leg size, while hind wing length was positively associated with the proboscis, abdominal, thoracic, body length and hooks. Morphometric variations found in A. mellifera of guinea agro-ecological zone could significantly impact conservation and future bee breeding programmes of Nigeria.