Schwarziana quadripunctata is a small, stingless bee found in a stretch of the South American Amazon[dubious – discuss] from Goiás, Brazil, through Paraguay, to Misiones, Argentina.

[1] This highly eusocial insect constructs earthen nests in the subterranean level of the subtropical environment, an unusual feature among other stingless bees.

The closest relative of S. quadripunctata is the species Schwarziana mourei, determined through morphological and genetic evidence collected in the early twenty-first century.

[4] The distribution of S. quadripunctata ranges from the central highlands of Brazil down towards the northern edge of Argentina on the eastern side of South America.

[2] However, their population is believed to have declined by nearly sixty-five percent (65%) over the past few decades due to competition with the introduced Africanized honeybees[2] along with human deforestation.

However, through Tom Wenseleers' "Caste Conflict Hypothesis," it is believed that dwarf queens are evolutionarily advantageous in that they develop in order to avoid becoming a worker bee.

With the queen’s role in production complete, the combs are left to the tending of worker bees, which distribute nutrients and vital resources to the growing larvae.

The relative concentrations of hydrocarbons in members of a colony differed between unrelated sites, alluding to the hypothesis that the wax of each nest contains a unique chemical blend from which the developing larvae absorb.

It has been determined that S. quadripunctata navigates, like many other bees, through the use of magnetoreception – utilizing magnetic fields in the atmosphere to recognize differences in location, altitude and directionality.

[13] This notion of magnetic navigational skills was first observed in a 2005 study conducted by Esquivel et al. on a S. quadripunctata nest near Rio de Janeiro, Brazil.

The primary control experiment confirmed that the majority of the nest had a preferential exiting angle in accordance with the local geomagnetic field.

[13] A similar 2005 study by Lucano et al. observed the same nest of Schwarziana quadripunctata to determine the location of the bodily magnetoreceptors.

After separating the head, thorax, abdomen and antennae of a dozen stingless bees, magnetic fields were applied to each body part.

The antennae of the stingless bee, therefore, exist as a complex sensory organ used for orientation and navigation through the combined use of thousands of hair-shaped sensilla.

[15] As multiple virgin queens approach the age of reproductive success, they begin to accumulate the reddish-brown pigmentation associated with adult members.

[15] Some virgin queens will begin manipulating the cerumen (wax) layers[15] in preparation for the construction of brood cells by the workers.

[4] Since S. quadripunctata reproduction typically relies on a single queen, genetic relatedness within individual colonies is expected to be relatively high.

[11] This value has been replicated in several studies, including one conducted by Toth et al. (2001) among eighteen colonies in Brazil (relatedness value = 0.75 ± 0.04 among worker bees).

For instance, researchers compared the relative amounts of various hydrocarbon compounds present in the epicuticles, serving as a chemical odor to other individuals, of S. quadripunctata.

They then charted these hydrocarbon differences and found a distinct separation according to colony location, age, sex, and hierarchal position.

Some of these essential hydrocarbons were also found to be lacking in younger individuals, alluding to the idea that the chemicals are acquired as the exposure to the waxy comb, specific to each colony, increases.

[12] The recognition of various odors associated with hydrocarbon concentrations is also responsible for the ability of worker bees to determine the location of their home nest.

[5] The subtropical environment of the South American Amazon provides a vast array of dietary options for a stingless bee such as S. quadripunctata.

With such a densely populated niche of pollinating insects, it remains of utmost importance to balance competition and resource acquisition.

It is often adverse weather conditions, rather than complete depletion of pollen and nectar from the resource, that terminate the length of harvesting by the stingless bees.

Over ten percent (10%) of their diet comes from the species Casearia sylvestris (called guaçatonga) and Myrcia tomentosa (commonly referred to as goiaba-brava) alone.

Other popular flowering plants comprising their diet include Mikania catharinensis, Piptocarpha oblonga (or braço-do-rei in Brazil), and Cordia trichoclada.

It must remain large enough to allow the easy to-and-fro passage of the bee, yet small enough to dissuade potential predators (such as orb spiders) from causing havoc inside the nest.

This is a distinct comparison to the complex entryways consisting of layered entrances or closable doorways observed in some other related species.

Through the observation and measurement of several S. quadripunctata nests near São Paulo, Brazil, entrances were discovered to have an average area of 14.5 square millimetres (3⁄128 sq in).