The moth is out from late May to early July, sometimes later.
This is also a marsh-loving species, and is generally plentiful in the fens of Norfolk, Suffolk, and Cambridgeshire; in the Southern counties it is either very local or, owing to its small size, has escaped detection, but has been noted as occurring in Surrey (Wisley), Kent (Deal), Hants (New Forest), Dorset, Devon, Cornwall, and Somersetshire; also in Yorkshire (Askham bog), and in Cumberland. The Welsh counties in which it has been found are Pembroke, Glamorgan and Carnarvon (Abersoch). It is locally common in Clydesdale, and has also been reported from Kirkcudbrightshire, and Perthshire. In Ireland it abounds in the boggy parts of Kerry, and is more or less frequent in several other parts of Ireland. Near Castle Bellingham, co. Louth, where it is common, a second brood was observed on Aug. 1st, 1894.
Its range abroad extends to Amurland and Japan.
The Rosy Marbled (Erastria venustula).
Another local species, but a frequenter of drier localities than the last two. This delicate rosy-flushed whitish moth first became known as a native of Britain by the capture of a few specimens in Essex. Stephens, writing in 1830, remarks, "I have hitherto seen four examples only—a pair in my own cabinet; one of the latter taken, I believe, in Epping forest by the late Mr. Honey, the other by the late Mr. Bentley." No other British specimens seem to have been recorded until 1845, when the late Mr. H. Doubleday, in July, noted several of the moths disporting themselves over, or settling upon, bracken in Epping Forest. For many years Loughton and some other parts of the forest remained the only known English haunts of the species, but in 1874 it was found commonly in
St. Leonard's Forest, Sussex; later still, it was discovered in the Brentwood district, Essex. It still occurs in all these localities, but appears to be now less frequently noticed in the original one than formerly (Plate [21], Fig. 9).
The caterpillar feeds in July and August on the flowers of cinquefoil (Potentilla), and is said to eat bramble blossoms also. Hellins describes it as rich brown, with a row of eight dusky-red diamonds down the back, enclosing the dorsal line of brighter red. The moth is out from the end of May and in June; it may be put up from herbage during the day, but its proper time of flight is in the early evening, and then only when the weather is favourable. If cold or damp the insects will not get on the wing. (Plate [25], Fig. 3; after Hofmann.)
The range abroad extends to Amurland.