70.120 (1787) Argent and Sable Rheumaptera hastata hastata (Linnaeus, 1758)

Status
Resident. Local.
UK BAP Priority Species.
 
Flight period
J F M A M J J A S O N D
























 
History
Lennon (1860) stated "I had the good fortune this year to take a fine variety of Melanippe hastata: it is larger and finer than the common kind, with much more pure white, and a fine pure white fringe, running round both wings." Writing in 1864, Lennon had found it at Tinwald Downs and near Barnkirk on the Lochar Moss (VC72) and also at Dalskairth (VC73). Thomas Rae Bruce had also recorded it from Slogarie (VC73) on 7th July 1879. Buchanan White (1895) listed it as occurring in Colvend parish. Gordon (1919) found it to be common and generally distributed, but being scarce of late. It had been noticed flying along stone dykes where bracken occurs on moorland in June.
 
MOGBI with their dot distribution maps included the species for all three VCs, the records sometime between 1961-81. Records occurred throughout the 1970s and 1980s, but for the 1990s there are only two records. All these latter records were in Kirkcudbrightshire and Wigtownshire.
 
Records continued in the 21st century but only a handful at most for each year. All this paucity of records is possibly down to observer coverage, rather than the scarcity of the species, probably due to the rough moorland terrain it keeps and the difficulty in walking over this.
 
Adults fly during the day from late May to early July, especially in warm and sunny weather.
 
Life cycle
One generation. Overwinters as a pupa in plant debris. Larvae are present July and August in a 'spinning' that it constructs by fastening the leaves together of its foodplant. On birch the leaf appears triangular or 'samosa' like in shape, while it is a domed cylindical spinning on bog myrtle. The caterpillar is of a glossy black with fine golden markings along its flanks, which become more extensive as the caterpillar grows.
 
Larval foodplants
Downy Birch, Silver Birch and Bog-myrtle.
 
Identification
The black and white pattern on the wings makes it easily recognisable, but the Small Argent and Sable is similar, but is smaller, has a straighter forewing costa and the central dark band across the forewing is rarely broken.
 
Both forms occur in the region: the smaller race, nigrescens, is a moorland species the caterpillar of which feeds on bog myrtle, while hastata feeds on small birch trees.
 
Habitat
Damp moorland and rough grassland.
© Richard Mearns, Grobdale Lane, 25 July 2005

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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