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Acrocercops cocciferellum(Chrétien, 1910).
Belongs to the Family GRACILLARIIDAE, this is a family of Leaf Miners.
Leaf miner is a term used to describe the larvae of many different species of insect which live in and eat the leaf tissue of plants. The vast majority of leaf-mining insects are moths (Lepidoptera) and flies (Diptera), though some beetles and wasps also exhibit this behavior.
Like Woodboring beetles, leaf miners are protected from many predators and plant defenses by feeding within the tissues of the leaves themselves, selectively eating only the layers that have the least amount of cellulose. In attacking Quercus robur (English oak) they also selectively feed on tissues containing lower levels of tannin, a deterrent chemical produced in great abundance by the tree.[1]
The precise pattern formed by the feeding tunnel is very often diagnostic for which kind of insect is responsible, sometimes even to genus level. The mine often contains frass, or droppings, and the pattern of frass deposition, mine shape and host plant identity are useful to determine the species of leaf miner. A few mining insects utilise other parts of a plant, such as the surface of a fruit.
Some patterns of leaf variegation are part of a defense strategy employed by plants to deceive adult leaf miners into thinking that the leaf has already been predated.
Gracillariidae is an important family of insects in the order Lepidoptera and the principal family of leaf miners that includes several economic, horticultural or recently invasive pest species such as the horse-chestnut leaf miner, Cameraria ohridella.
There are 98 described genera of Gracillariidae (see "Subfamilies and Genera"). A complete checklist is available of all 1809 currently recognised species (de Prins and de Prins 2005). There are many undescribed species in the tropics but there is also an online catalogue of Afrotropical described species [1]; the South African fauna is quite well known. Although Japanese and Russian authors have recognised additional subfamilies (de Prins and de Prins, 2005), there are three currently recognised subfamilies, Phyllocnistinae of which is likely to be basal. In this subfamily, the primitive genus Prophyllocnistis from Chile feeds on the plant genus Drimys (Winteraceae), and has leaf mines structurally similar in structure to fossils (Davis, 1994) (see "Fossils"). While there have been some recent DNA sequence-based studies of Palaearctic species (Lopez-Vaamonde et al., 2003, 2006), there is need for a satisfactory modern global phylogenetic framework for the subfamilies of Gracillaridae. Some genera are very large, e.g. Acrocercops, Caloptilia, Cameraria, Epicephala and Phyllonorycter.
Gracillariidae occurs in all terrestrial regions of the World except Antarctica.
These generally small (wingspan 5-20 mm.) moths and are leaf miners as caterpillars[2] which can provide a useful means of identification especially if the hostplant is known. The subfamilies differ by the adult moth resting posture (Davis and Robinson, 1999). Most Gracillariinae rest with the front of the body steeply raised; Lithocolletinae and Phyllocnistinae rest with the body parallel to the surface, or in Lithocolletinae often with the head lowered.
The first to fifth-instar larvae are flattened and possess specialised mouthparts adapted for feeding on sap. Older-instar larvae are cylindrical and have normal chewing mouthparts for feeding on plant tissue within the leaf mines, and have a fully functional silk-producing organ the "spinneret". Some genera have an intermediate stage in this remarkable hypermetamorphosis (Davis and Robinson, 1999).
Fossils
The family is an old one, with fossil Phyllocnistinae mines known from 97 million old rocks in Kansas and Nebraska (Labandeira et al. 1994). There are other fossil mines known from rocks of Eocene and Miocene age (de Prins and de Prins, 2005). There are also two adult moths are known from from Lithuanian or Baltic amber of Eocene age: Gracillariites lithuanicus Kozlov, 1987 and G. mixtus Kozlov, 1987) (de Prins and de Prins, 2005).
Source:http://en.wikipedia.org/wiki/Gracillariidae
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