outward's picture

Moth eggs

Observed: 11th September 2010 By: outwardoutward’s reputation in Invertebratesoutward’s reputation in Invertebrates

I first thought the forsythia leaf was discoloured an unusual grey, then I admired the precision geometrical array. The eggs hatched a few days later. Minute looping caterpillars which descended on fine silk threads and escaped through the gauze base of my cage. The leaf was not eaten at all. Forsythia is an alien plant with no pests in UK.


No identification made yet.

Species interactions

No interactions present.


BeckyH's picture



Blewit Boy's picture


Presumably it must be a species of Geometrid moth, from your description of "looping caterpillars". Not sure which ones feed on Forsythia, if indeed this was its food plant, and it may not be, if you say they weren't eating the leaves. Although, I would've thought it likely that the mother would lay her eggs on the food plant.


Michael Skelton's picture


I once found a similar batch on a leaf of a shrub. The caterpillars also appeared to loop when newly hatched. In time they proved to be Large Yellow Underwing, which feed on various low plants. It may be that the female usually lays large batches on shrubs and the caterpillars then disperse to feed on plants such as dandelion.

jorj's picture

Wonderful photos - Would make

Wonderful photos - Would make a good design for textiles. Nature is just the best designer!


rimo's picture

The only moth species listed

The only moth species listed on DBIF as feeding on Forsythia are Brown-Tail, Privet Hawk and Caloptilia syringella, but we can rule all of those out immediately on basic morphology.
These do look much more like the eggs of a noctuid species than a geometer - as Michael says, Large Yellow Underwing lays eggs in these great sheets (as do several other yellow underwing species, including broad-bordered). YUW eggs also have the fluting seen here, so I'd strongly suspect one of those species - probably Large or BB from the timing. The females aren't very fussy where they lay their eggs, and frequently begin laying in the trap, or as soon as you pot them up - the larvae of both species eat virtually any low-growing plant, so there's not too much point in the female wasting energy finding the perfect spot!

Record your ladybird sightings!

outward's picture

Large Yellow Underwing

We have had a Large Yellow Underwing trapped by the lamp in our conservatory so I would be happy with this identification.

Blewit Boy's picture

You might've mentioned..........

You might've mentioned that before outward! ;)