3.1. Life Cycle
The CLM is a holometabolous insect, its life cycle includes different stages 
). Considering a 25 °C temperature, the egg stage usually lasts about five days, the larval stage lasts about twelve days, and the pupae lasts about five days, totaling approximately 22 days until reaching adulthood 
. Total life cycle varies according to temperature, relative humidity, and rainfall. In the dry season, the attack of the pest is generally more severe than in wet periods 
Figure 2. L. coffeella life stages from egg to adult. After hatching the egg, (a) the larvae development is divided into four instars: L1 (b), L2 (c), L3 (d), and L4 (e). The last instar forms a cocoon and turns into pupa (f). The adult emerges (g) from the pupa to mate. Eggs are laid over the adaxial side of the coffee leaf and the cycle restarts. Temperature rising accelerates and shortens the cycle span time, as detailed.
The egg is about 0.3 mm, made by a translucent structure, with an oval, concave shape, and expanded sides 
. After hatching, the larvae leave the underside of the eggs, which are in contact with the upper leaf epidermis, and get into the leaves 
Figure 3. L. coffeella egg hatching and mine progression: (a) Unhatched eggs have a translucent structure, the arrow indicates a freshly oviposited egg; (b) after hatching, the eggshell becomes darker (white arrow) and the larva penetrates the leaf under the egg and starts feeding, forming a light green mine (black arrow); (c) enlargement of the mine. The black arrow indicates the dark color of the mine due to residues left behind by the larva.
The L. coffeella
larval phase has four instars 
. Newly hatched larvae have a translucent whitish color, but throughout their development they take on a greenish yellow tone. The last larval instar is about 4–5 mm, flattened, segmented with 11 segments, and yellowish in color 
a). Fourth instar larvae have a flat head and mouthpiece of the chewing type (Figure 4
b,c), prolegs, and crochets 
Figure 4. Immature stages of L. coffeella. (a) Ventral view of a fourth instar larva. Arrow indicates proleg; (b) flat head in front view; (c) chewing mouthpiece; (d) crochets (arrow) located in proleg. Morphology details to distinguish the immature stages are described in the text; (e) pupa’s sea cocoon; (f) pupae’s dorsal (a), and ventral (b) shapes.
After accomplishing the larval stages, the larvae leave the mines and weave a silk X-shaped cocoon, usually in the axial region of the leaf, forming the pupae 
e). Pupae have an approximate length of 2 mm, milky color, small black eyes, antennas, and legs ventrally fused, and wrinkled wings 
f). Usually, more pupae are found in the “skirt” region of coffee plants, which is the underside of the plant where dead leaves accumulate 
From the pupae, adults emerge with an average body length of 2 mm and a wingspan of 6.5 mm (Figure 5
a). They have a head with “white hair scales”, long antennae that reach the end of the abdomen, silver white chest, legs covered with white bristles, wing with three rows of yellow bristles at the apex with a black circle, yellowish abdomen and covered with white scales and genital organs covered by a tuft of white scales 
b,c). A recent description of the sexual polymorphism 
shows the differentiation of the structures present in both male and female genitalia: male—bulbus ejaculatorius, valve, gnathos, and aedeagus and female—ovipositor, sclerite, and corpus bursae. Overall, the female whole body is similar to the male, except by a slightly longer average length.
Figure 5. L. coffeella adults (a) perched on coffee leaf; (b) male seen by ventral view, with white scales all over the body; (c) closed caption of the wings apex from dorsal view to show details: black circle surrounded by yellow bristles.
3.2. Larval Feeding Behavior
CLM is a monophagous pest, coffee exclusive and the larvae are the causal agent of the crop damage 
. When feeding on the mesophyll of the coffee tree leaves, the insect creates mines that justify the common name of the pest—coffee leaf miner (Figure 6
a). The mines cause necrosis (Figure 6
b) and reduce the photosynthetic leaf surface (Figure 6
c,d), leading to a lower photosynthetic rate of the plants and consequent depletion of the plant and productivity diminish 
. The damage caused by this insect includes defoliation 
e). Eventually, without adequate cultural treatments, the infestation can lead to the death of the plant.
Figure 6. Damage to coffee leaf caused by the CLM larvae. (a) Initial mine formation; (b) mine developed, with large necrotic area; (c) larvae inside the mine; (d) leaf with impaired photosynthetic surface; (e) coffee defoliation.
A relationship between the feeding damage of CLM and the application of synthetic fertilizers has been described in the literature 
. The amount of free amino acids and reducing sugars in the metabolic system of coffee plants is related to nutritional imbalance and susceptibility to pests. Plants fertilized with organic material showed a decrease of up to 50% of leaf mines