Walking the 50km of trails at REGUA is fascinating for birders and naturalists alike. Altitudinal range spans 30 – 2000m and there is a richness of invertebrates and plants to match the diversity of birds that draws the majority of visitors to REGUA. All classes of arthropod are present in abundance and there are many interesting patterns of distribution waiting to be identified and investigated.
REGUA’s lodge garden has a roofed, whitewashed wall complete with mercury vapour lamp generating many new records of moths for the Reserve and for Rio State. The wall often reveals a wealth of other interesting invertebrates such as this Dobsonfly (Corydalidae). Many of these creatures are difficult to see in the forest probably because they are residents of the tree canopy.
In the forest there are chance encounters with exciting species such as the White Witch Moth (Thysania agripina) Noctuidae with a huge wingspan.
December to Febuary is the Brazilian summer and usually a hot rainy season and time of maximum plant growth. This is, of course, an excellent time for all insects and amphibians. Whilst August to November is the Brazilian Spring and busy for birdwatching, it is also good for insects. Only March to July are a little quieter.
There is a profusion of wonderful butterflies. Some, like the 88, (Diaethria clymena) are very common. The most famous neotropical butterflies belong to the Genus Heliconia, with their distinctive strap-shaped wings and bright colours. These insects were shown to have co-evolved with their food plant, the different species of passion-vine (Passiflora). The vines put out new shoots irregularly and the butterflies must live a long time to be able to search out new growth and lay a full complement of eggs.
Another spectacular group of insect are the various species of huge Morpho butterflies which flit through the forest under-storey.
Diptera are interesting and diverse. There are three common sources of food that can provide for a profusion of flies: dung, carrion and some species of freshly emerged fungus. Parasitoid ichneumonids and tachinids search out the larvae of butterflies and moths whose living tissues they will feed on until they finally cause their death.
Ants are predators, roaming leaf and shoot for opportunities or different species will farm leaves with the help of fungus.
Spiders must guard against predatory wasps and some of these are very large indeed.
Beneath the placid exterior of the forest, termites work to undo the conversion of CO2 to sugar; every now and then a crash is heard acr
oss the forest as another giant tree succumbs to their tiny jaws.
There is much work to do to find out how many species of arthropod exist in these rich habitats. We are only in the earliest of stages investigating how all these myriad species interact in Mata Atlântica.