''Leipomeles dorsata ''is a
neotropical
The Neotropical realm is one of the eight biogeographic realms constituting Earth's land surface. Physically, it includes the tropical terrestrial ecoregions of the Americas and the entire South American temperate zone.
Definition
In bioge ...
paper wasp
Paper wasps are Vespidae, vespid wasps that gather fibers from dead wood and plant stems, which they mix with saliva, and use to construct nests made of gray or brown papery material. Some types of paper wasps are also sometimes called umbrell ...
that is found across
Central America
Central America ( es, América Central or ) is a subregion of the Americas. Its boundaries are defined as bordering the United States to the north, Colombia to the south, the Caribbean Sea to the east, and the Pacific Ocean to the west. ...
and northern
South America
South America is a continent entirely in the Western Hemisphere and mostly in the Southern Hemisphere, with a relatively small portion in the Northern Hemisphere at the northern tip of the continent. It can also be described as the southe ...
.
It is a
eusocial
Eusociality (from Greek εὖ ''eu'' "good" and social), the highest level of organization of sociality, is defined by the following characteristics: cooperative brood care (including care of offspring from other individuals), overlapping generat ...
wasp with little differentiation between reproducing and non-reproducing females.
In fact, workers can become temporary reproductives if the main reproductives are killed, allowing reproduction to continue until the main reproductive population recovers.
The colony cycles through different ratios of main reproductive females and subordinate reproductive females, starting with few or no primary reproducing females, and increasing until there are only main reproductives.
Taxonomy and phylogeny
''L. dorsata '' is part of the tribe
Epiponini
The Epiponini (formerly known as Polybiini) are a large and diverse tribe of social wasps inhabiting the Neotropical region, with some species' ranges extending into the Nearctic region.
Selected species
* ''Apoica pallens''
* ''Leipomeles d ...
, a group of neotropical eusocial wasps.
This species has a complex taxonomic history. Other species have been synonymized into this species, the first being by Fabricus in 1804.
The initial classification of the species ''Polybia nana ''became ''Leipomeles nana ''in 1912 and was eventually synonymized with ''L. dorsata.''
''L. nana ''was the junior synonym and ''L. dorsata'' is the senior synonym.
However, ''L. nana'' has since been reclassified as its own distinct species, ''Leipomeles spilogastra'', and is no longer a synonym of ''L. dorsata.''
Description and identification
''L. dorsata '' females are a variety of colors, varying between chestnut to dark brown. Shade generally varies with age, with individuals becoming darker in color as they get older. However, egg-laying females sometimes exhibit yellow patterns on the head and
thorax
The thorax or chest is a part of the anatomy of humans, mammals, and other tetrapod animals located between the neck and the abdomen. In insects, crustaceans, and the extinct trilobites, the thorax is one of the three main divisions of the cre ...
.
The
abdomens
The abdomen (colloquially called the belly, tummy, midriff, tucky or stomach) is the part of the body between the thorax (chest) and pelvis, in humans and in other vertebrates. The abdomen is the front part of the abdominal segment of the torso. ...
of this species are generally an elongated diamond-like shape and the wings have a flattened semi-circular shape.
Nest Identification
''L. dorsata'' nests are made of extremely thin material classified as paper.
These nests may or may not have a
petiole.
If there is a petiole present it is covered in a sticky substance that protects the nest against
ants
Ants are eusocial insects of the family Formicidae and, along with the related wasps and bees, belong to the order Hymenoptera. Ants evolved from vespoid wasp ancestors in the Cretaceous period. More than 13,800 of an estimated total of 22,00 ...
, which are brood
predator
Predation is a biological interaction where one organism, the predator, kills and eats another organism, its prey. It is one of a family of common feeding behaviours that includes parasitism and micropredation (which usually do not kill th ...
s.
The nests are a series of combs underneath the leaf, and may be fused.
Generally, this species applies colored pulp to the outside of the nest, thought to be a method of
camouflage
Camouflage is the use of any combination of materials, coloration, or illumination for concealment, either by making animals or objects hard to see, or by disguising them as something else. Examples include the leopard's spotted coat, the ...
.
Distribution and habitat
''L. dorsata'' is a
neotropical
The Neotropical realm is one of the eight biogeographic realms constituting Earth's land surface. Physically, it includes the tropical terrestrial ecoregions of the Americas and the entire South American temperate zone.
Definition
In bioge ...
species present in the
rainforests
Rainforests are characterized by a closed and continuous tree canopy, moisture-dependent vegetation, the presence of epiphytes and lianas and the absence of wildfire. Rainforest can be classified as tropical rainforest or temperate rainforest ...
of Central and
South America
South America is a continent entirely in the Western Hemisphere and mostly in the Southern Hemisphere, with a relatively small portion in the Northern Hemisphere at the northern tip of the continent. It can also be described as the southe ...
. They build their nests on the underside of large tree leaves, making them extremely adapted to a niche of the rainforest habitat.
It is mainly found in the
lowland
Upland and lowland are conditional descriptions of a plain based on elevation above sea level. In studies of the ecology of freshwater rivers, habitats are classified as upland or lowland.
Definitions
Upland and lowland are portions of ...
areas of these forests from 50 to 500m elevations.
Large scale morphological studies rely mostly on collections from Costa Rica.
Colony cycle
This species has a distinct colony cycle, with primary egglayers only being part of the colony for a limited amount of time.
Reproductives of ''L. dorsata'' consist of primary yellow egg layers and
subordinate
A hierarchy (from Greek: , from , 'president of sacred rites') is an arrangement of items (objects, names, values, categories, etc.) that are represented as being "above", "below", or "at the same level as" one another. Hierarchy is an important ...
brown egg layers.
The yellow females have longer ovaries than the brown females.
This is likely due to the brown egglayers being former worker wasps that have become egg layers in the colony.
All of the yellow egg layers are older females, but there is usually a mix between ages in the brown egg layers.
This occurs when a colony is deprived of its yellow egg layers, the brown workers are signaled to become replacements,
an example of cyclical oligogyny.
Eventually, the older yellow egg layer population recovers and the workers aggressively prevent other females from becoming egg layers.
Behavior
Reproductive suppression
When the population of primary egg layers is robust, workers aggressively suppress reproduction by other workers. This aggression is exhibited between nest mates, through denying food and physically biting rivals.
Older mature primary egglayers will suppress reproduction in the younger brown egglayer population. However, if the colony begins losing its primary reproductives then it is advantageous for the colony if the subordinate (brown) egg layers reproduce, and they will do so since they are no longer suppressed by the yellow egglayers.
Communication
''L. dorsata'' display trail marking during colony migration, which is rather common for
neotropical
The Neotropical realm is one of the eight biogeographic realms constituting Earth's land surface. Physically, it includes the tropical terrestrial ecoregions of the Americas and the entire South American temperate zone.
Definition
In bioge ...
swarming wasps.
The scouts will drag or rub the underside of their bodies on surfaces, such as leaves along the migration route.
However, what makes ''L. dorsata'' unique is that it lacks the Richard's Organ, which is generally associated with
pheromone
A pheromone () is a secreted or excreted chemical factor that triggers a social response in members of the same species. Pheromones are chemicals capable of acting like hormones outside the body of the secreting individual, to affect the behavio ...
production in other species that exhibit this behavior.
Mating behavior
As is the case of most
Epiponini
The Epiponini (formerly known as Polybiini) are a large and diverse tribe of social wasps inhabiting the Neotropical region, with some species' ranges extending into the Nearctic region.
Selected species
* ''Apoica pallens''
* ''Leipomeles d ...
wasps, the reproductives stay in the nest, which requires males to find their way into the nest to mate.
An explanation for the male's ability to find potential mates is that they patrol for mates and follow colony migration
pheromones
A pheromone () is a secreted or excreted chemical factor that triggers a social response in members of the same species. Pheromones are chemicals capable of acting like hormones outside the body of the secreting individual, to affect the behavio ...
that were laid down by scouts to new nest sites.
In fact, males have been sighted at ''L. dorsata'' colonies as soon as the first day of nest construction.
In addition, males then might also be attracted by reproductives' own pheromones inside of the nest, and use those to find their way into the nest to mate.
Kin selection
Worker queen conflict
''L. dorsata'' is a species that does not have queens per se, but rather multiple egg layers that are in charge of reproduction.
The degree that these egg layers are specialized for reproduction depends on how functional their ovaries are. There are four patterns of ovaries that were observed in this species: no
oocytes
An oocyte (, ), oöcyte, or ovocyte is a female gametocyte or germ cell involved in reproduction. In other words, it is an immature ovum, or egg cell. An oocyte is produced in a female fetus in the ovary during female gametogenesis. The female ge ...
, immature
oocytes
An oocyte (, ), oöcyte, or ovocyte is a female gametocyte or germ cell involved in reproduction. In other words, it is an immature ovum, or egg cell. An oocyte is produced in a female fetus in the ovary during female gametogenesis. The female ge ...
, well-developed oocytes with at least one mature oocyte, and several well-developed and completely mature
oocytes
An oocyte (, ), oöcyte, or ovocyte is a female gametocyte or germ cell involved in reproduction. In other words, it is an immature ovum, or egg cell. An oocyte is produced in a female fetus in the ovary during female gametogenesis. The female ge ...
.
The females with the more mature reproductive organs are the ones that have greater reproductive success because they are more specialized; in cases where there are both brown worker egg-layers with the third reproductive pattern and yellow reproductives with the fourth reproductive pattern, the yellow females out perform and outcompete the brown ones.
However, if there are no yellow females present than the brown workers may be solely responsible for the colony's reproduction.
Life history
Colony survivorship
''L. dorsata ''has several qualities that allow for high colony survivorship. The main quality is that they display cyclical oligogyny.
This allows workers to temporarily take the place of egg layers when there are few or no egglayers, allowing the population to survive during a period of high egglayer mortality.
Also the ability of male
Epiponini
The Epiponini (formerly known as Polybiini) are a large and diverse tribe of social wasps inhabiting the Neotropical region, with some species' ranges extending into the Nearctic region.
Selected species
* ''Apoica pallens''
* ''Leipomeles d ...
to find nests with virgin females contributes to colony survivorship.
This ensures that copulation can take place in colonies where there has been loss of reproductives which guarantees the reproductive success of the colony.
Camouflage
''L. dorsata ''builds its nests in a way that disguises it from vertebrae
predator
Predation is a biological interaction where one organism, the predator, kills and eats another organism, its prey. It is one of a family of common feeding behaviours that includes parasitism and micropredation (which usually do not kill th ...
s.
They choose an overhanging leaf and build the nest underneath it so that it is hidden, and then proceed to construct an
envelope
An envelope is a common packaging item, usually made of thin, flat material. It is designed to contain a flat object, such as a letter or card.
Traditional envelopes are made from sheets of paper cut to one of three shapes: a rhombus, a shor ...
that mimics the color and patterns of the leaves surrounding the nest.
This mimicry results from the addition of colored leave pulp. Wasps chew up leaves on the surrounding tree, and then applied the resulting mixture to the outside of the nest.
Interaction with other species
Predators and predation
''L. dorsata'', as with other paper wasps mainly feed on insects and other
arthropods
Arthropods (, (gen. ποδός)) are invertebrate animals with an exoskeleton, a Segmentation (biology), segmented body, and paired jointed appendages. Arthropods form the phylum Arthropoda. They are distinguished by their jointed limbs and Arth ...
that they find by foraging.
The main predators of ''L. dorsata'', as with other neotropical paper wasps, are ants and birds that feed on a variety of insects.
Specifically,
army ants
The name army ant (or legionary ant or ''marabunta'') is applied to over 200 ant species in different lineages. Because of their aggressive predatory foraging groups, known as "raids", a huge number of ants forage simultaneously over a limit ...
present a grave threat to paper wasps in the tropics, and nests and behaviors have evolved as a way to combat this predation pressure; in the case of ''L. dorsata, ''this is seen in the chemical defense described below.
Defense
In the case of ''L. dorsata, ''defense is passive rather than active. Nest
petioles are covered in a sticky substance that protects the nest and the larva inside from ants.
This protection is perhaps the reason that this species has extremely docile females.
In many species that employ this method, the small size of the wasps requires alternate defense systems rather than aggression. Other examples include chemical defense and large numbers of adults at the foundational stage.
References
External links
* Fernando Noll Research Gate profile (much work on
Epiponini
The Epiponini (formerly known as Polybiini) are a large and diverse tribe of social wasps inhabiting the Neotropical region, with some species' ranges extending into the Nearctic region.
Selected species
* ''Apoica pallens''
* ''Leipomeles d ...
): https://www.researchgate.net/profile/Fernando_Noll/publications
* Encyclopedia of Life page: http://eol.org/pages/30391310/overview
{{Taxonbar, from=Q18345857
Vespidae
Hymenoptera of South America
Insects described in 1804