Nothobranchius boklundi is distinguished from all other species of the genus by a unique combination of characters in females that consist of pale red elongate spots over the dorsal and anal fin rays only; males similar to the other members of the N. brieni species-group and differing from all other species of the genus by the caudal and anal fin proximal portions being spotted with a broad light submarginal band and dark margin, the absence of a dark margin on the dorsal fin, the absence of spots on the head and no black margin to the scales (Ref. 84038). This species differs from the other members of the N. brieni species-group by the regular reticulated pattern on the body; its light blue iris; the caudal fin having a dark margin, its proximal portion with red dots or spots; dorsal fin without light margin, without distinct black spots anteriorly; anal fin completely covered with irregular rows of red spots, distal portion yellow and border not distinctively pigmented (Ref. 84038).