by Matthew Cobb
Outside my office I have a stupendous poster of the fly tree of life, showing the evolutionary relationships of the world’s flies, along with some lovely photographs. (You can download the poster from here.) This tree was produced to accompany a scientific article from 2011 describing the evolution of flies, which Jerry covered here.
When I have an idle moment, I like to inspect the tree for odd flies that I don’t know about and then find out about them. Which is how I came to be mooching around the web looking for the Ctenostylidae, which turn out to be a particularly weird group of 14 species about which very little is known. Here’s one (a male Sinolochmostylia sinica from China, taken from here):
Why are they weird? Well they have
- No ocelli (most insects have three small eyes (‘ocelli’ in Italian) on the top of their heads, used for detecting movement and in flight)
- No proboscis (this means they presumably don’t eat as adults)
- Branched aristae (part of the antenna) in females (most flies have feather-like aristae)
- They are viviparous (technically larviparous, as they lay larvae, like tsetse flies – NB that link might be NSFL)
They are probably parasitoids and may be nocturnal/crepuscular, but nothing is known of their ecology, or even their true distribution – they are found mainly in tropical regions, but also in Nepal, Korea and China. Their current taxonomic position, based on molecular analysis, is within the Tephritoidea – so they are related to the true fruit flies (Tephritidae) and the delightfully named flutter flies or Pallopteridae. You can learn about as much as we know about the Ctenostylidae by reading these two articles.
The fact that we have no idea about how these flies live should be no surprise. Most people in the world now live in cities, and we don’t know about the flies that live there, either. In 2012 the Natural History Museum of Los Angeles County launched a research initiative called NHM Biodiversity Science: City and Nature (NHM BioSCAN), with the aim of surveying the biodiversity of one of the world’s great cities.
In a sampling period lasting a mere three months, they discovered 30 new species of fly – not simply species that weren’t known in LA, California, or even the USA. These were species that had never been identified before, and there they were, buzzing about in an urban environment. Furthermore, those flies were from just one genus (a group of species, this one is Megaselia) called phorid flies. This suggests that other genera may hold similar richness.
Here’s a picture of the flies they found:
There’s a great post by Emily Hartop describing how she made the discovery, and the work she did with her boss, Brian Brown, and with the great English dipterist, Henry Disney.
There’s a nice couple of brief videos about BioSCAN. The first describes the project, the second shows how ordinary citizens are getting involved:
Look carefully around you, and you will be amazed by the diversity of life that can be seen, even if you live in a city. Next on my list from that Fly Tree of Life poster? Maybe the Neurochaetidae, also called upside-down flies. As of now, I know nothing about them, but they sound intriguing, and knowledge is only a few clicks away…