99-million-year-old termite-loving thieves caught in Burmese amber

April 13, 2017
The oldest termitophile from 99-million-year-old Burmese amber, Cretotrichopsenius burmiticus. Credit: Cai et al., 2017

Eusocial insects, such as ants, social wasps and bees, and termites, include some of the most ecologically ubiquitous of terrestrial animals. The nests of these insects are well protected and provide a safe, communal space for the storing of resources and production of brood, so the nests are often cohabited by various highly specialized symbionts that take advantage of the abundant resources and protection inside the nests.

Recently, a research team led by Dr. CAI Chenyang and Prof. HUANG Diying from Nanjing Institute of Geology and Palaeontology (NIGPAS) of the Chinese Academy of Sciences reported the oldest horseshoe-crab-shaped, obligate termite-loving rove from mid-Cretaceous Burmese amber. These fossils represent the oldest known termitophiles, which are able to hack into a termite and exploit their controlled physical conditions to steal plentiful resources (e.g., fungi) inside it. The discovery reveals that ancient termite societies were quickly invaded by beetles about 99 million year ago.

Termitophiles, symbionts that live in , include a wide range of morphologically and behaviorally specialized organisms. Understanding of the early evolution of termitophily is challenging due to a scarcity of fossil termitophiles, with all known reliable records deriving from the Miocene Dominican and Mexican ambers (approximately 19 million years ago). Mesozoic termitophiles are of great significance for understanding the origin of eusocial societies of termites and the early evolution of specialized termitophily.

To integrate into the hosts' societies, termitophilous beetles have repeatedly evolved physogastry (swollen abdomens) and limuloid (horseshoe-crab-shaped) body shapes, representing the two principal forms. Both morphological adaptations have arisen convergently many times in beetles (Coleoptera) as well as in flies (Diptera).

Ecological reconstruction of the mid-Cretaceous termitophille. Credit: Cai et al., 2017

The peculiar fossil rove beetles, named as Cretotrichopsenius burmiticus Cai et al., 2017, exhibits the characteristic features of the modern aleocharine tribe Trichopseniini, including the articulation of the hind leg whereby the coxae are fully fused and incorporated into the metaventrite.

Cretotrichopsenius burmiticus has a protective horseshoe-crab-shaped body form typical of many modern termitophiles, with concealed head and antennae and strong posteriorly directed abdominal setae. The discovery represents the earliest definitive termitophiles, pushing back the fossil record of termitophiles by 80 million years.

Recent species of Trichopseniini are usually associated with derived neoisopteran termites of Rhinotermitidae, and less frequently with Termitidae. Interestingly, some trichopseniines are known to live within nests of the basal-most termites (Mastotermitidae) and drywood termites (Kalotermitidae).

Because host specificity is rather low in extant trichopseniines, it is certainly likely that Cretotrichopsenius may have been associated with the variety of termite groups known from Burmese amber. The fossils reveal that ancient termite societies were quickly invaded by beetles about 99 million years ago.

The result was published in Current Biology on April 13th, 2017. This study was jointly supported by the Chinese Academy of Sciences, the National Natural Science Foundation, the Natural Sciences Foundation of Jiangsu Province, and the Ministry of Science and Technology of China.

Explore further: Intact mushroom and mycophagous rove beetle in Burmese amber leak early evolution of mushrooms

More information: Current Biology, DOI: 10.1016/j.cub.2017.03.009

Related Stories

Brazilian scarab beetles found to be termitophiles

January 13, 2015

Termite soldiers are able to chemically detect intruders in their colonies. While most trespassers are swiftly dealt with, some spiders, centipedes, millipedes, and insects are allowed to find shelter within termite nests. ...

Finding the first fungus farmers

July 5, 2016

The development of farming was a key milestone in human history, but as a species we were quite late to the party. Insects got there first! One of the best documented examples happens in the termite world, where some species ...

100-mllion-year-old amber preserves oldest animal societies

February 11, 2016

Fighting ants, giant solider termites, and foraging worker ants recently discovered in 100-million-year-old amber provide direct evidence for advanced social behavior in ancient ants and termites—two groups that are immensely ...

The World's oldest farmers

June 22, 2016

An international team of researchers has discovered the oldest fossil evidence of agriculture, not by humans, but by insects.

Recommended for you

How to cut your lawn for grasshoppers

November 22, 2017

Picture a grasshopper landing randomly on a lawn of fixed area. If it then jumps a certain distance in a random direction, what shape should the lawn be to maximise the chance that the grasshopper stays on the lawn after ...

Ancient barley took high road to China

November 21, 2017

First domesticated 10,000 years ago in the Fertile Crescent of the Middle East, wheat and barley took vastly different routes to China, with barley switching from a winter to both a winter and summer crop during a thousand-year ...

New paper answers causation conundrum

November 17, 2017

In a new paper published in a special issue of the Philosophical Transactions of the Royal Society A, SFI Professor Jessica Flack offers a practical answer to one of the most significant, and most confused questions in evolutionary ...

0 comments

Please sign in to add a comment. Registration is free, and takes less than a minute. Read more

Click here to reset your password.
Sign in to get notified via email when new comments are made.