The Moths of Suffolk
2289 Knot Grass, Acronicta rumicis, (Linnaeus, 1758)

National Status : Common

Local Status : Resident (SMP Status 1)

Distribution and abundance : Widespread and common, although apparently more infrequent in the south-west of the county

Habitats : Various open habitats; grassland, heathland, fens, scrub, gardens and open woodland

Flight Period : Reported as double-brooded; late April to June and August to early September. Local records have a slight peak from mid-April to late May with a much larger peak from mid-June to mid-August.

Larval foodplants : Various herbaceous and woody plants

Morley's Final Catalogue : Of quite frequent occurrence from Brantham to Beccles, and Aldeburgh to Brandon.

Wingspan details : Forewing 16-20mm, Wingspan 34-44mm

Identification

Confusion species
    AdultPoplar Grey, Acronicta megacephala
Scarce Dagger, Acronicta auricoma
Sweet Gale Moth, Acronicta euphorbiae
Coronet, Craniophora ligustri

Compare confusion species
    Adult

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Tunstall Common, Suffolk (29.vii.2006) © A Prichard

Flight chart
JFMAMJJASOND
4 19 9 100 67 2

Life history chart
JFMAMJJASOND
pupa pupa pupa pupa imago imago ovalarvaimago larva larva pupa pupa pupa

Further Photographs

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Eye (13.v.2000) © Paul Kitchener
Wolves Wood (31.v.2003) © A Prichard
Ipswich, Suffolk (iv.2003) © N Sherman
 
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Found by day - Ipswich, Suffolk (ix.2003) © N Sherman
VC25, Burgh Castle, Suffolk (27.iv.2010) © Brian Jones
Female - Ipswich, Suffolk (19.vii.2014) © Neil Sherman
 
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Larva found on Tayberry plant - Ipswich, Suffolk (17.ix.2014) © Neil Sherman
Ipswich, Suffolk (22.vii.2015) © Paul Kitchener