Fagus mexicana Fagus mexicana Fagus mexicana, the Mexican beech or haya, is a species of beech endemic to northeastern and central Mexico, where it occurs from southwest Tamaulipas south to Hidalgo and Puebla. It is restricted to high altitude cloud forests in the Sierra Madre Oriental. It is closely related to the American beech "Fagus grandifolia" and is usually treated as "Fagus grandifolia" subsp. "mexicana" (Martínez) E.Murray. "Fagus mexicana" is a deciduous tree, reaching heights of 25–40 m tall and up to 1 m trunk diameter. The leaves are alternate and simple, with a slightly toothed margin, usually smaller than those of
Stigmella hemargyrella Stigmella hemargyrella Stigmella hemargyrella is a moth of the Nepticulidae family. It is found in most of Europe, except Iceland, Norway, Finland, Portugal and most of the Baltic region. The moths (imago) are bivoltine flying from April to May and again from July to August and can be found resting on trunks. The wingspan is 5–6 mm. The egg can be laid on either side of the leaf and the pale yellowish-white larva feed, within a mine on "Fagus sylvatica" and "Fagus sylvatica orientalis". The mine is a sinuous gallery and at the early state is relatively narrow with a