There is a form of Polygala myrtifolia with narrow leaves, the margins rolled under slightly. Maybe it isn’t quite the same as P. pinifolia, although the distinction isn’t upheld by the authorities. The photo shows narrow leaves and distinct vein lines across the floral parts and the crests white.
There is also a P. teretifolia bearing cylindrical leaves and P. scabra, the latter with narrow but hairy and channelled leaves.
P. myrtifolia var. pinifolia is found in the Western Cape and the Eastern Cape. It is not considered to be threatened in its habitat early in the twenty first century (Vlok and Schutte-Vlok, 2015; Manning, 2007; iNaturalist; http://redlist.sanbi.org).