Condensing enzyme that elongates saturated and monounsaturated very long chain fatty acids, to yield products up to 30 carbons in length. a very-long-chain acyl-CoA + H(+) + malonyl-CoA = a very-long-chain 3-oxoacyl-CoA + CO2 + CoA No expression in adults. In D.melanogaster, functions in the elongation of long-chain C27 and C29 hydrocarbons. However, no expression is detected in D.simulans adult females or males which synthesize only short-chain C23 and C25 hydrocarbons. Belongs to the ELO family.