Ringlet

Ringlet Aphantopus hyperantus (Linnaeus 1758)

Family: Nymphalidae, subgroup Satyrinae (The Browns)

Description

Photos by Martin Partridge

The Ringlet is around the size of a Small White, but almost black when freshly emerged, fading to brown with wear. The upperwings are plain black-brown with a variable number of small, white-pupilled black circles highlighted by yellow or orange rings (eyespots or ocelli). Similar, but usually larger and more strongly marked ocelli can be seen in on the underside when wings are closed, and are a key feature to separate from Meadow Brown.

The Ringlet is robust to poor weather, being one of the few butterflies which can be seen flying in cloudy conditions and occasionally even in rain.

Habitat

The Ringlet is a creature of moist and sheltered grasslands where it can flutter around a dappled jungle of tall plants in air which is damp and still. It can be found on wastelands, in rough pastures, conservation headlands and old-fashioned meadows. It also haunts the edges of rivers and streams and is common along the verges of road and rail routes as well as being found along woodland edges and rides, and in clearings. Wanderers may also turn up in gardens. It can occur in drier areas such as along the sand dunes of Spurn NNR or on the chalk pastures of the higher Wolds, although numbers are usually lower on such sites.


In the Wolds, many of the valleys run east/west and the Ringlet usually occupies the cooler north-facing slopes, which are thick in mosses, whilst all the other species are found on the drier, hotter south-facing sides, which have a completely different flora. The butterfly is particularly prone to suffer from drought conditions, especially where this shrivels up grass growth when larvae are active. The 1976 drought caused a crash in numbers whilst the notably hot year of 2003 was also very wet and therefore a good one for the Ringlet.

Distribution

Historically a species of the S and E of the county, Ringlet has completed its expansion through Yorkshire (part of a wider push northwards and into Scotland) and can now be seen county-wide, including occasionally at relatively high altitudes (300–400 m). Populations are fairly stable, showing less fluctuation from year to year than many species, but trends over recent years suggest a shallow decline may be ongoing.

Nevertheless, Ringlets often appear in quite large numbers, and site counts in the hundreds are not uncommon. In 2020, a count of some 467 individuals at Rawcliffe Bridge (nr Goole, VC63) was the highest for several years.

Overall, Ringlet is one of the most widespread butterfly species in England and Wales. It was historically absent from much of the north of England (including northern and western parts of Yorkshire) and Scotland. However, a fairly rapid expansion has seen most gaps in its English distribution closed (although Lancashire, somewhat mysteriously, remained largely Ringlet-free until very recent years). This expansion continues unabated into Scotland. National abundance trends are also positive for this species.

Life Cycle

Ringlet is strictly a single-brooded species throughout its global distribution. Occasional records beyond mid-September are more likely to be aestivating individuals (a behaviour better known from the related Meadow Brown) than evidence of a second brood. In Yorkshire, the flight period typically extends from late May to late August, peaking around the beginning of July. However, individual colonies are often short-lived, flying for only a few weeks within the countywide flight period.

Non-adhesive eggs are dropped in flight or ejected whilst females sit on grass heads. Initially, each dome-shaped egg is a pale primrose yellow and the shell glossy and transparent. Larvae can be seen through the shell prior to hatching after about 18 days. Once hatched, they feed until about late Oct then partially hibernate after the 3rd instar. Feeding continues whenever conditions are mild, although growth is slow. Later stage larvae are easiest to find by torchlight at night. They reach about 2cm in length by June and then pupate at the base of grass tussocks, emerging after about a fortnight.

As eggs are simply ejected into grassy areas, often whilst the female is flying, it is difficult to track down the range of grass species used by the large, but this is thought to be quite restricted. Thomas & Lewington (1991) note Cock’s-foot Dactylis glomerata and Wood False Brome Brachypodium sylvaticum as favourites, whilst Emmet & Heath (1989) give Tufted Hair-grass Deschampsia cespitosa as frequently used, and Creeping Bent Agrostis stolonifera as less commonly used. A wider range of grasses has been accepted in captivity.

Status

The species is not under threat.

Aberrations

Very variable with 35 recognised aberrations, mainly associated with the number, size and shape of the ocelli. In ab arete Miller, the rings are missing, leaving white pupils on a small black spot, whilst ab obsoleta Tutt lacks even the white pupils. One of the most striking variations is ab lanceolata Shipp where the ocelli are teardrop shaped. In ab caeca Fuchs the underside spots are restricted to the hindwings and reduced to white specks. In ab pollens the upperside is a pale yellowish brown. All these varieties have been recorded in Yorkshire.

CM 28/12/20