In Robson's time, 'Generally distributed [...] but not common, and only recorded by a few collectors'. [...] In Durham the records are clustered around the Team and lower Wear valleys, along the rivers where P. arundinacea grows. It is common on Waldridge Fell, and at Chester-le-Street, where TCD frequently finds the larvae, but always on Reed Grass and never on Carex spp. It should occur in the Derwent valley, but the only record here is by J. R. Johnson at Winlaton Mill in 1933: Sheppard and Eyre never found it there in spite of intensive research in the 1970's. J. P. Robson had it at Barnard Castle, but not until 1936, and J. W. H. Harrison found larvae at Norton, in the south of the county where a series of wet areas are ideal for the growth of Phalaris. It occurs in the Hamsterley Forest trap every year, and the highest record is from Salter's Gate, where evidence of larvae was found on a N.N.U. Field Meeting in 1968.