Photo © Alec Harmer

Old World Webworm

Hellula undalis

Checklist Number
63.061 [B&F: 1360]

Verification
Record will require further evidence, at least a good photograph, unless CMR is aware recorder has confidence in identification

Classification

Family:Crambidae
Subfamily:Glaphyriinae
Genus:Hellula
Species:undalis
Authority:(Fabricius, 1781)

A widespread species from Africa across Asia to the Pacific: historically a rare immigrant to Europe, numbers are increasing, perhaps in part due to human transportation with the brassica crops it feeds on (for which it can be a commercially important pest species). The first record is presumed to have arrived on these shores as an immigrant on the basis of a specimen taken at a light-trap near East Prawle, Devon, on 28 September 1967, but there were no further records until 1988 since when it has been almost annual with an unprecedented 70+ individuals reported nationally in 2011: the majority have been in south-west England. In our area it is far rarer: the first (and so far only) record for the Isle of Wight came in 1989, with the first for VC11 in Hurn (Dorset) in October 2001, another on the VC11/12 boundary at Crawley in Oct 2006, a (very late) third in December 2015: 2023 saw a significant influx nationally, with a further two recorded in the county.

The abundance in each month is indicated as follows:

No records
Very occasional
Irregular
Uncommon
Off-peak, but not unusual
Off-peak, but not unusual
Main flight time
J F M A M J J A S O N D
Adult
Larval

Records by week (adult)

Records by week (larval)

No Larval records to show.

VC10 Isle of Wight

Site Date Quantity Recorder Stage
Freshwater (SZ38)26/10/1989oneSam Knill-JonesAdult

VC11 South Hampshire

Site Date Quantity Recorder Stage
Hurn (SZ19)16/10/2001oneMike JeffesAdult
Lymington (SZ39)19/12/2015oneAlec HarmerAdult
Marchwood (SU30)30/09/2023oneChris ThainAdult
Fareham (SU50)01/10/2023oneKeith WheelerAdult
Fareham (SU50)01/10/2023oneKeith WheelerAdult

VC12 North Hampshire

Site Date Quantity Recorder Stage
Northwood (SU43)12/10/2006oneReg A BellAdult