Conservation Biology of Lycaenidae (Butterflies) - IUCN

Conservation biology of Lycaenidae: A European overview
Miguel L. MUNGUIRA 1 , José MARTIN 1 and Emilio BALLETTO 2
1 Departamento de Biología, Universidad Autónoma de Madrid, Cantoblanco, 28049 Madrid, Spain
2 Dipartimento di Biologia Animate, Università di Torino, Via Accademia Albertina 17, 10123 Torino, Italy
Biology of European Lycaenidae
The biology of European lycaenids is generally well known as
a result of both general and specific studies. A review of central
European species was made by Malicky (1969a) who dealt with
larval foodplants, phenology and overwintering stages.
Relationships with ants were also reviewed by Malicky (1969b)
and Fiedler (1990a, 1991). Books on regional faunas including
detailed ecological information on a species-by-species basis
are available for Italy (Verity 1943), the Netherlands (Tax
1989), British Isles (Ford 1970; Emmet and Heath 1989) and
Switzerland (SBN 1987). Specific autecological studies cover
a wide range of species from almost every major group within
the European fauna. Some of these studies are listed in Table 1,
together with the geographic areas in which they were
undertaken. Several studies in press or short notices have not
been listed and a wider range of species is covered by these.
Thus the information available covers roughly 50% of the
European lycaenids. The Table clearly shows wider coverage
of northern species and of the countries where the present
authors are based (Italy and Spain), but nevertheless it gives a
general idea of our knowledge of European lycaenids.
While most of the northern species are well known as far as
their biology is concerned, information on most Mediterranean
species is not available, even on such basic topics as foodplants
or habitat preferences. Greece, with its 12 endemic species, is
the area where basic studies are most urgently needed. High
altitude species are also under-represented in ecological studies
due to the difficulties of reaching their habitats for long-term
studies, but their conservation seems to pose fewer problems
than that of lowland species.
Synecological studies are generally less abundant and only
refer to some geographic areas such as southern France (Cléu
1950; Bigot 1952, 1956; Dufay 1961, 1965–66), Hungary
(Uherkovic 1972,1975,1976), Czechoslovakia (Kralichek and
Povolny 1978), Italy (Balletto et al. 1977, 1982a–e, 1985,
1988, 1989), Switzerland (Erhardt 1985) and Germany
(Kratochwil 1989a, 1989b, 1989c), or to some particular
ecosystems (Fouassin 1961; Janmoulle 1965; Cléu 1957;
Mikkola and Spitzer 1983; see also Ehrlich 1984).
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Larval foodplants
Most of the European lycaenids are polyommatines (Kudrna
1986). The data on lycaenid larval foodplants in Table 2 clearly
illustrate the fact that polyommatines have radiated in our area
more than the other groups, using wider niches and evolving to
produce a wider range of endemic species and peculiar ecotypes.
Life cycles
The most common strategy adopted by the European lycaenids
to endure adverse seasons is larval quiescence. Most
polyommatines hide away and spend the winter season (in
northern Europe) or the summer and winter (in the Mediterranean
areas) as second or third instar larvae. When the egg or pupa is
the overwintering stage, a diapause normally takes place (e.g.
Iolana iolas (Ochsenheimer), Tomares ballus (F): Munguira
1989, Jordano et al. 1990). Theclines typically overwinter as
eggs, lycaenines and polyommatines as larvae. In the last case,
however, there is considerable variation, again supporting the
idea of a wider radiation of the group in our area. Table 3
summarises the data on overwintering stages for Spanish
lycaenids (a sample covering 70% of European species).
There is one generation per year for most species. This
seems to be a clear adaptation to temperate climates which have
a favourable summer and a cold winter in which insect life
comes through a dormant period. All the theclines follow this
pattern, but again the polyommatines show some variation,
having species with two generations (e.g. Polyommatus [or
Lysandra] bellargus (Rottemburg), Lycaeides idas (L.)) or as
many generations as weather allows (e.g. Tarucus theophrastus
(F.), Aricia cramera Eschscholtz, Polyommatus icarus
(Rottemburg)). It is possible that species with two generations
are not 'fixed' to this condition, but constrained by food
availability or unfavourable weather conditions. Thus, many
species with a low number of generations may increase the
number when resource limits change. An example of this is
Polyommatus icarus with one generation in northern Britain,
two in southern Britain (Emmet and Heath 1989) and four to
five in Spain (Martin 1982).