This checklist, compiled by Glyn Collis, first appeared in Mulholland (2012). The four-digit number preceding each species name is the Bradley-Fletcher species code.
1545 Clouded Yellow, Colias croceus Gibson & Hopkins (1998), Gibson (2000)
1549 Large White, Pieris brassicae Gibson (1990), Gibson & Hopkins (1998)
1550 Small White, Pieris rapae Gibson (1990)
1551 Green-veined White, Pieris napi Gibson (1990, 2000)
1553 Orange-tip, Anthocharis cardamines Gibson (2000, 2004)
1555 Green Hairstreak, Callophrys rubi Gibson (1990)
1557 Purple Hairstreak, Neozephyrus quercus Sutcliffe (2008)
1561 Small Copper, Lycaena phlaeas Gibson (1990)
1574 Common Blue, Polyommatus icarus Gibson (1990)
1590, Red Admiral, Vanessa atalanta Gibson (1990)
1591 Painted Lady, Vanessa cardui Gibson (1990)
1593 Small Tortoiseshell, Aglais urticae Gibson (1990)
1597 Peacock, Inachis io Gibson (1990, 2000)
1600 Small Pearl-bordered Fritillary, Boloria selen Gibson (1990)
1607 Dark Green Fritillary, Argynnis aglaja Gibson (1990)
1610 Marsh Fritillary, Eurodryas aurinia Sutcliffe (2008)
1614 Speckled Wood, Pararge aegeria Mulholland (2012)
1615 Wall Brown, Lasiommata megera Sutcliffe (2009), also Gibson (1990, 2004)
1618 Scotch Argus, Erebia aethiops Gibson (1990, 2004)
1621 Grayling, Hipparchia semele Gibson (1990)
1626 Meadow Brown, Maniola jurtina Gibson (1990)
1627 Small Heath, Coenonympha pamphilus Gibson (1990)
1629 Ringlet, Aphantopus hyperantus Gibson (2004)
Number of species 23.
As noted by Gibson (1990) and Sutcliffe (2008) there is also an eighteenth century record of a Large Skipper Ochlodes venta from Bute (Thomson 1980, p28). At least since the time when Thomson was writing, the range of this species in Scotland has been largely confined to Dumfries and Galloway and south Ayrshire (see also Futter et al 2006).
References
Futter, K., Sutcliffe, R., Welham, D., Welham, A., Rostron, A.J., MacKay, J., Gregory, N., McCleary, J., Tait, T.N., Black, J. & Kirkland, P. (2006). Butterflies of South West Scotland. Argyll Publishing, Glendaruel.
Gibson, J.A. (1990). The butterflies of the Island of Bute. Transactions of the Buteshire Natural History Society, 23: 41-45.
Gibson, J.A. (2000). Additional notes on the butterflies of the Island of Bute. Transactions of the Buteshire Natural History Society, 25: 91-92.
Gibson, J.A. (2004). Recent notes on Bute butterflies. Transactions of the Buteshire Natural History Society, 26: 91-92.
Gibson, J.A. & Hopkins, I. (1996). The Clouded Yellow butterfly on the Island of Bute. Transactions of the Buteshire Natural History Society, 24: 76.
Mulholland, N. (2012). The Speckled Wood – a new butterfly for Bute, with a checklist of Bute’s butterflies. Transactions of the Buteshire Natural History Society, 28: 64-65.
Sutcliffe, R. (2008). Bute butterflies. Transactions of the Buteshire Natural History Society, 27: 85-86.
Sutcliffe, R. (2009). Recent changes in the distribution of some Scottish butterflies and the arrival of new species in Scotland. Glasgow Naturalist 25 (2) 5-12.
Thomson, G. (1980). The Butterflies of Scotland. Croon Helm, London.