Conservation Biology of Lycaenidae (Butterflies) - IUCN

workers of the same ant, Anoplolepis longipes (Jerdon) (Kitching
1987).
In many cases, relationships between myrmecophily or
aphytophagy and oviposition patterns are not as clear as in
Allotinus Felder & Felder. Laying eggs in clusters ('clustering')
in many Australian Lycaenidae is strongly associated with
obligate myrmecophily (Kitching 1981), but this is not the case
for neotropical Riodininae, in which myrmecophilous species
lay eggs singly (Callaghan 1986). In the latter group, clustering
is associated with gregarious behaviour. Myrmecophilous
riodinine larvae are solitary, and gregarious larvae are not
myrmecophilous. The latter may be aposematic and conspicuous,
so that their protection against many predators is a function of
their distastefulness. Many myrmecophilous larvae, in contrast,
are rather cryptic, and accompanying ants may help to prevent
them being attacked by predators and parasitoids.
Such relationships between caterpillars and ants are thus of
central importance in considering the evolution and biology of
Lycaenidae and have attracted much attention.
Myrmecophily and evolution in lycaenids
Symbiosis with ants may have been an early development in the
evolution of Lycaenidae (Eliot 1973), and both Hinton (1951)
and Malicky (1969) suggested that ancestral lycaenids were
myrmecophilous. Contrary to Pierce's (1987) conclusion that
the distribution of myrmecophily in Lycaenidae does not reflect
phylogeny, Fiedler (1991a, 1991b) believed that there was a
strongly phylogenetic relationship present.
However, there is some possible confusion over roles of
myrmecophily in lycaenoid evolution as their influences on
Riodinines and the other taxa may be markedly different (De
Vries 1991a). Not only are they the most common basis for
suggesting ecological groupings in the family (Henning 1983),
but the evolution of lycaenid diversity itself may also be
involved. Pierce (1984) suggested that lycaenid diversity may
reflect speciation in relation to other butterfly families, and that
this could be influenced by larvae/ant associations in two
important ways:
1. Female lycaenids may adopt ants as oviposition cues
(Fiedler and Maschwitz 1989, on Anthene emolus (Godart)) so
that the presence of ants on a novel foodplant may induce a
rapid host switch. Although few such 'oviposition mistakes'
(Pierce 1984) may actually lead to range extensions, it may be
more important for a given lycaenid to retain a particular ant
association than a particular foodplant, and an increase in the
number of ovipositions on different foodplants may increase
the number of opportunities for subsequent speciation.
Essentially, novel foodplant choices may be made by female
lycaenids to an unusually high degree because they select for
ants as well as for chemically and physically suitable foodplants.
A 'new' hostplant may occupy a different ecological range
from those utilised earlier, and population isolates could thus be
formed.
2. The general non-vagility of many lycaenids results in
their occurrence in small, semi-isolated populations with rather
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little regular genetic interchange between them. Pierce (1983)
showed that a deme of the Australian Jalmenus evagoras
(Donovan) may be restricted to a single Acacia tree, where
males aggregate and compete for emerging females so that
variability in male reproductive success effectively reduces
population size further. Such patchy distributions (also noted in
the North American Glaucopsyche lygdamus Doubleday: Pierce
1984) occur in spite of apparent continuous foodplant availability
and it is quite possible that they result from selection of
foodplant areas which are high in nitrogen, as well as having the
required ants. Many myrmecophilous lycaenid larvae actively
prefer nitrogen-rich foodplants and plant parts such as seed
pods and flowers. This may be explained in part by the need to
supply ants with amino acids as a 'nutrient reward' for tending
the larvae (Pierce 1984).
Larval feeding
The overall importance of plant-feeding to caterpillars of
Lycaenidae differs substantially between different subfamilies,
and those of some groups rarely take plant food. As far as is
known, all species of Poritiinae and Lycaeninae are normally
phytophagous. Some Curetinae are phytophagous. Lipteninae
are also plant feeders, but are highly unusual amongst butterflies
in that larval food usually consists of algae, fungi or lichens (see
Cottrell 1984, for summary). Most genera of the two largest
subfamilies, Theclinae and Polyommatinae, appear to be
phytophagous or opportunistically carnivorous with varying
degrees of dependence on prey. Maculinea van Eecke and
Lepidochrysops Hedicke larvae are phytophagous when young,
but the late instars are obligate predators of ant larvae. Other
aphytophagous genera are noted in Table 1. Both Liphyrinae
and Miletinae appear to be entirely aphytophagous, and the
unlisted genera in Table 1 reflect ignorance of their larval
biology, rather than known phytophagy. Liphyra Westwood
and Euliphyra Holland larvae are probably specific feeders on
early stages of tree ants (Oecophylla spp): their larvae are
flattened and have a heavily armoured cuticle which enables
them to withstand ant attacks. The pupa of Liphyra remains
inside the last larval skin, which thereby functions as a puparium.
Aslauga larvae are predators of Homoptera, at least as late
instars. Eggs of Miletinae are typically laid near colonies of
Homoptera, including aphids, coccids and membracids and
some, at least, are found on a wide range of different hostplants.
Although the larvae are predominantly predators, some younger
instars may also feed on honeydew or other insect secretions
such as aphid cornicle secretions.
Selection of foodplant species by phytophagous species,
and their effects on foodplants, are difficult to study. Flower
predation of a range of perennial herbaceous legumes by
Glaucopsyche lygdamus in Colorado differed substantially
between species (Breedlove and Ehrlich 1972), with either
Lupinus or Theropsis being by far the most heavily attacked
plant at each of a series of sites. On both plant genera, flowerfeeding
can markedly reduce seed-set (Breedlove and Ehrlich
1968,1972). Whereas G. lygdamus females select inflorescences