72. Lopinga achine (Scopuli, 1763) / Woodland brown / Nymphalidae – Satyrinae
NL: boszandoog / D: Gelbringfalter / F: bacchante
Photographs: Frits Bink ©.
Medium-sized or large, wing length 25 (24-26) mm. The species occurred up to about 1920 in Luxemburg and up to 1926 in Wallonia in open forest with a well-developed grass undergrowth.
Butterfly is on the wing from early-June until early-July, peaks mid-June. The species is known from sub-continental and continental climates, amplitude 8 to 18. Required heat sum 700°d and maximum tolerated 1800°d, corresponding climate windows 22 and 35 weeks.
The butterfly is a very striking appearance but not easy to observe because it stays most of the time up in the tree canopy, presently declining strongly in Europe.
Behaviour over time
Overwintering: half grown larva in third instar, 10-13 mm in length, hidden in a grass tussock or litter layer.
Reproduction: oviposition starts after 2-3 days when the body contains 42 (36-48) eggs, observed potential production 2.5 times as much.
Larval feeding periods: 59 (52-66) days in summer and autumn and in next spring 34 (29-40) days from late-April until early-June.
Generations: always one.
Spreading of risk: not observed.
Life cycle: egg about 12 days; larva 44-47 weeks; pupa 18 (15-20) days.
Life span of adult: short, 2 weeks.
Photographs: Frits Bink ©.
Behaviour in space
From stay-at-home to migrant: stay-at-home, spatial requirement modest.
Finding a mate: male patrols and perches.
Orientation in the landscape: open wood with a grass undergrowth.
Oviposition: eggs dropped from resting place in a tree.
Threats from other organisms: vulnerable, no defence.
Threats from the environment: very sensitive to drought, in all stages.
Adult: honeydew from coccids and aphids in the tree canopy and also from puddles.
Larva: when young, the larva eats old leaves, in spring young shoots. Melica nutans and Carex montana are examples of grasses which produce nutritious shoots early in the spring.
Plant species: Cyperaceae, Carex montana, C. remota, Poaceae, Festuca rubra, Melica nutans.
Rearing experiment based on specimens originated from Buttle, Gotland, Sweden:
15 July 1982: 2 females captured in a wood of Scotch pine, Norwegian spruce, juniper, rowan and willow, with an undergrowth of mountain sedge, nodding melick and wood false-brome.
17 July: two females produced 83 eggs in the first day.
29 July: eggs hatched.
9 August: larvae first instar (in a host-plant selection test mountain sedge (Carex montana) was preferred).
11 August: larvae moulted, they have 'tails'.
13 September: larvae 10-11 mm in length, third instar, spent most of daytime at the tip of the stems.
3 October: larvae appeared to have stopped feeding, they are now 11-13 mm in length.
26 March 1983: one pot with four larvae taken indoors.
3 April: larvae were feeding and preferred the sunny side of the pot.
8 April: all in moult.
18 April: larvae nearly fully grown (host-plant test: wood millet and chalk false-broom refused).
25 April: first pupa.
12 May: first adult emerged.
15 May: 5 males emerged.
25 May: last adult emerged.
Parallel series after overwintering:
26 March: second pot remained outside.
8 May: larvae in last instar.
12 May: larvae full grown.
15 May: one larva fed on carnation grass (Carex panacea).
23 May: two females appeared.
9 June: last adult hatched.
Table 72-1. Results of dissections
Note: data of Karlson & Wiklund 1985: egg production 107 per female, longevity 11 and 14 days.
Table 72-2. Collection and observation localities
D, Steigerwald, 49° 39’N – 10° 23’E; 24 July 1984.
S, Gotland, Buttle 57° 25’ 09”N – 18° 34’ 38”E; 15 July 1982, 6 July 2004, seen c. 30 butterflies, not seen any 16 July 2004.
Fig. 72-1. Lopinga achine, phenogram adapted from Ebert & Rennwald 191b: 142.
Fig. 72-2. Lopinga achine, habitat characteristics.
Fig. 72-3. Lopinga achine, climate matrix, heat-sums 700 - 1800°d.