Monthly Archives: May 2011

Sometimes, working on poorly known groups is just…

Biologists like to glorify the discovery of new  taxa. Let that be species, genera, what say you. If this taxa has a spinal column and is extinct, contact Nature or Science, your CV points just went up.

In reality, this is not a big deal at all. You work on a poorly explored taxonomic group, you will find new taxa.

Arnett, already said it: the aleocharine staphylinids are the most taxonomically difficult group among the beetles, and represent close to 3% of all described life. Unfortunately, there are very few taxonomically informative characters.

Seevers, one of the deities among aleo. researches, eluded that the maxilla holds a taxonomic gold mine of characters. Unfortunately, he never was able to make sense of it.

All the lacinia you ever wanted

Don’t worry, I’m here, trying to help. A small sub-set of the true diversity, but if you look carefully, there is some sense in nonsense.

The remarkable Hoplandria larvae

Most aleocharine larvae are bland – elongate cream colored squishy things, maybe a pair of stemma, maybe a somewhat prominent pair of articulating urogomphi. Overall, the larvae have few diagnostic characters and identification relies havily on chaetotaxy.

The larvae of Hoplandria speices are another deal all together though.

Hoplandria larva

Only recently described, the larvae of this genus have extraordinarily elongate appendages, an obliquely attached sensory appendage (of the antennae), and spatulate setae near the apex of their femora.

Hoplandria larval head

Another interesting note is that they seem to have extremely reduced pygopods. Pygopods are the terminal pseudo-legs of larval beetles. Analogous to the spongy legs of moth and butterfly caterpillars, the larvae use these fleshy hooked pseudo-legs to push themselves forward, or anchor onto substrates. Hoplandria larvae, on the other hand, walk around with their rear end up in the air, stilting around with their long walking legs.

After reading Thayer et al. 2004, I hadn’t gotten the chance to see these remarkable larvae until a trip to Costa Rica in 2010. Then, I was sifting some forest leaf litter and this particular larva was spotted in my sorting pan. With the characteristic walk, I knew immediately what it was.

It’s not everyday you can field identify an aleocharine larva on the spot. Careful descriptions and behavioral observations are crucial, and can be priceless for identification.