70.079 (1769) Spruce Carpet Thera britannica (Turner, 1925)

Resident. Common.
Flight period

Lennon (1862-63) lists Thera simularia as occurring at Dalskairth, with Thera simulata at Whinney Hill and found to be "not common." Both these names are synonyms for Chestnut-coloured Carpet according to Kloet & Hincks (1972). However, simulata and simularia are under virgata as synonyms in Stainton's (1859) two volume work, and surely this is all Lennon would have had to work from. After much confusion, it therefore seems likely that Lennon's records are under the correct species.
Gordon (1919) under T. variata, another synonym, found it common in fir woods around Corsemalzie (VC74) but very variable. Earliest date was 12th June 1897, with the latest being on 12th October 1898.
William Evans received specimens from Mowat, the Killantringan lighthouse keeper during 1913 to aid his insect migration studies.
Sir Arthur Duncan (1909-84) during his lifetime had found it at Closeburn, Dumfriesshire.
In 1976 it was trapped on six occasions at the Rothamsted station at Penninghame (VC74), with a further five records from the Mabie Forest station during 1989-92.
From 1989 when it was caught in Kilsture Forest to 2010, there were five hundred and twenty records, with the regular trapped sites at Kirkton, Durisdeer, Cally Woods, Kirkcudbright, Kirriereoch, Kirkland and Old Torr featuring heavily among the records, with the rest from widely scatteres sites across the region.
Life cycle
Two overlapping generations. Overwinters as a small larva from the autumn to May, and again, June and July, with pupation taking place close to the ground.
Larval foodplants
Larvae feed on many other conifers than spruces, including pines, firs, cedars and occasionally cypresses.
Great care is needed in separating the Thera species, especially Spruce Carpet from Grey Pine Carpet. Apparently there are no consistent differences in the genitalia of these two species, but the males can be separated by viewing the antennae through a hand lens in good light. Spruce Carpet's having a pronounced 'shoulder' at the distal end.
Coniferous plantations, but also most other habitats where the conifer foodplants are found.
© Keith Naylor, Dyke Farm NR, Moffat, 16 August 2005
© Alison Robertson, Bowhouse Park, 1 May 2011

Local distribution map

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Distribution map displays records from the National Biodiversity Network (See terms and conditions).

The following datasets are included:

  • Butterfly Conservation - Macro-moth provisional distribution for the British Isles (excluding the Republic of Ireland) from the National Moth Recording Scheme
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