As summer starts kicking into high gear in the United Kingdom, these graceful beauties can be found on the wing. A shocking scarlet, cardinal beetles get their namesake due to their colourful resemblance to the vestments of cardinals (no surprises there). For your strange insect fact of the day, a report from 2000 describes a male P. serraticornis feeding on cantharadin secrections from an oil beetle.
Cardinal beetles are generalist predators, chowing down on a wide variety of small invertebrates. They also occasionally take pollen. Their larvae live within decomposing wood, feeding on fungal hyphae and small invertebrates.
There are a couple species of beetles in the UK which are similar. Two rarer types of cardinal beetle can be found. The Black-headed Cardinal beetle (Pyrochroa coccinea), is slightly larger and is a deeper blood red. Finally, the Scarce Cardinal beetle (Schizotus pectinicornis) has a black head like P. coccinea but is only about half the length. It is rare, with an extremely local distribution.
Nardi, G., Bologna, M.A., 2000. Cantharidin attraction in Pyrochroa (Coleoptera: Pyrochroidae). Entomol. News 111, 74–75.
The Wildlife Trusts., 2015. Red Headed Cardinal Beetle. http://www.wildlifetrusts.org/species/red-headed-cardinal-beetle
This is one of my absolutely most favourite beetles. I was shown my first one by my friend Richard, who found it in a very serendipitous moment on a night-time hunt. They’re slow, but faster than you think – a minotaur can slip into its tunnel faster than one would expect. I also came across this beautiful little beetles on Ramsey Island in Pembrokeshire, a gorgeous RSPB reserve known for its fabulous dung beetles (along with seabirds, choughs, pergrines, rare lichens, and a welcoming and knowledgable staff). Looking forward to searching out a couple of my own this weekend in Oxfordshire.
March 19th is Taxonomy Day, a 24-hour period dedicated to the science of defining where biological organisms belong, based on their common characteristics. If the mnemonic “Kings Play Chess On Fine Green Silk” is familiar, you’ve already had a lesson in taxonomy. This represents how we classify organisms from the most broad category (Kingdom), all the way down to the finest (Species).
For my Taxonomy Day post, I chose to focus on two species I am very familiar with Aphodius fimetarius and Aphodius pedellus. These species of dung beetles superficially look almost identical, and nobody realised that they were completely different species until they were kayotyped. This is a process where the chromosomes of an organism are isolated, stained, and examined under a microscope. When several different representative beetles of this brilliant beetle were examined under the scope, their chromosomes were completely different. There weren’t any examples of individuals where chromosomes looked like a mixture of the two types, meaning there were no instances of hybridisation.
Scientists then realised that the species had different morphological characteristics as well. One species had a more densely punctured pronotum than the other. Even more striking differences were found when the aedeagus (male genitals) of the two different species were compared. As the characteristics of individual beetles vary greatly from one to the next, it can be easy to lump things into species when they look the same. Through collaborations between traditional taxonomy, and new molecular methods – we can learn more about the wonderful diversity that often remains hidden out of sight.
Miraldo, A., Krell, F.-T., Smalén, M., Angus, R. and Roslin, T. 2014. Making the cryptic visible – resolving the species complex of Aphodius fimetarius (Linnaeus) and Aphodius pedellus (de Geer) (Coleoptera: Aphodiidae) by three complementary methods. Systematic Entomology 39: 531–547.
Going to try out a new post form, a small series of quick little bits about beautiful British beetles, which unimaginatively is called “Beautiful British Beetles”. I chose Nicrophorus vespilloides as my first beetle to feature. Please let me know what you think.