Wyeomyia smithii, the pitcher plant mosquito, is an inquiline

Inquiline

In zoology, an inquiline is an animal that lives commensally in the nest, burrow, or dwelling place of an animal of another species. For example, some organisms such as insects may live in the homes of gophers and feed on debris, fungi, roots, etc...

 invertebrate found only in the phytotelma of the purple pitcher plant, Sarracenia purpurea

Sarracenia purpurea

Sarracenia purpurea, commonly known as the purple pitcher plant, northern pitcher plant, or side-saddle flower, is a carnivorous plant in the family Sarraceniaceae...

. In this microcommunity of bacteria, rotifer

Rotifer

The rotifers make up a phylum of microscopic and near-microscopic pseudocoelomate animals. They were first described by Rev. John Harris in 1696, and other forms were described by Anton van Leeuwenhoek in 1703...

s, protozoa

Protozoa

Protozoa are a diverse group of single-cells eukaryotic organisms, many of which are motile. Throughout history, protozoa have been defined as single-cell protists with animal-like behavior, e.g., movement...

, and midge

Midge

A midge is a very small, two-winged flying insect. "Midge" may also refer to:-Real:* Midge Costanza , American politician* Mildred Gillars , aka "Midge", American broadcaster of Nazi propaganda during World War II...

s, W. smithii is the top-level predator; its presence determines the bacterial species diversity within the pitcher.

Wyeomyia smithii is a model organism for the study of photoperiodism

Photoperiodism

Photoperiodism is the physiological reaction of organisms to the length of day or night. It occurs in plants and animals.Photoperiodism can also be defined as the developmental responses of plants to the relative lengths of the light and dark periods...

, the biotic process of controlling seasonal life history

Biological life cycle

A life cycle is a period involving all different generations of a species succeeding each other through means of reproduction, whether through asexual reproduction or sexual reproduction...

 events by measuring day length as a reliable predictor of the seasons. W. smithii enters a state of developmental arrest, larval diapause

Diapause

Diapause is the delay in development in response to regularly and recurring periods of adverse environmental conditions. It is considered to be a physiological state of dormancy with very specific initiating and inhibiting conditions...

, that is initiated and maintained by short daylengths and averted or terminated by long daylengths