(Morpho menelaus)
The Menelaus blue morpho (Morpho menelaus) is one of thirty species of butterfly in the subfamily Morphinae. Its wingspan is approximately 12 cm, and its dorsal forewings and hindwings are a bright, iridescent blue edged with black, while the ventral surfaces are brown. Its iridescent wings are an area of interest in research because of its unique microstructure. Due to its characteristic blue color, Morpho menelaus is considered valuable among collectors and was widely hunted in the 20th century. However, deforestation remains the main threat to the survival of this species. This neotropical butterfly is found in Central and South America, including the Cerrado which is a vast tropical savanna in Brazil. Other locations include Mexico and Venezuela. Ancestors of the Morpho menelaus butterfly may have been distributed in the Andean regions. There is great variation among the various species of Morpho. Two groups of Morpho butterflies, achilles and hecuba, are distinct in flight behavior and vertical forest distribution. This habitat stratification between the two forest levels may have led to the diversification of the Morpho butterflies. Flight pattern behavior may also have led to changes in the wing shape to make it more suitable for gliding or flapping. Phylogenetic studies suggest these are indicative of ancestral qualities. Morpho menelaus is part of the achilles subclade of Morpho. Within this species, there are no differences between males and females regarding forewing length, aspect ratio and wing centroid measurement which may be indicative of morphological homogeneity. Despite the popularity of the genus Morpho, there is not a general consensus on the number of species or on how these species are defined. For instance, some consider M. amanthonte a subspecies of Morpho melanus, but this is not supported by morphology. Some older studies have identified 75 Morpho species, and newer studies recognize about 30 species. Despite the many species of the Morpho butterfly displayed in collections, they usually have mismatched or missing abdomens which make it difficult for research. Using combined studies of parsimony and Bayesian analyses, Morpho melanus is associated with the M. helenor, M. sulkowskyi and M. amonthonte clades. The split of Morpho melanus from M. amonthonte is estimated to fall under the Pliocene era.