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Photo#92439
Eucnemid larvae - Dirrhagofarsus ernae

Eucnemid larvae - Dirrhagofarsus ernae
Nashua, Hillsborough County, New Hampshire, USA
January 10, 2007
Size: 6 - 18.5 mm
These are some of the eucnemid or False Click Beetle larvae I found in the soft, white-rot sapwood areas of an aspen trunk section that was suspended upsidedown in a tangle of bittersweet vines. Since I wasn't sure if these very slow-moving larvae would burrow their way into the white-rot chunks I brought home, I made sure not to dig them all out of their burrows. I want some at least to mature so an ID can be established.

I also contacted eucnemid authority Dr. Jyrki Muona to see if he can ID from larval images. He says he can but will have to get home from his travels first.

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Moved
Moved from Dirrhagofarsus.

Moved

Undescribed species
Latest word from Dr. Muona after examining specimens I sent him is that this species is completely undescribed, although there is a possibility another researcher is already in the process of describing it. In any case its description should be published in a year or less.

 
describing
I have been in contact with Dr. Muona on this matter. I came across this species in two other states since 1996. As soon as I extract the aedeagus from my own specimens, I will proceed with the description. If any larval specimen obtained, I would like a specimen or two for description purposes as well.

 
Hi Robert,
Although I appear to have found an undescribed species, I apparently was not the *first* to do so :-) Congratulations. I look forward to seeing your published description. I was apparently the first to find the larvae of this species, which I was obviously able to verify by rearing them.

I have been in close contact with Dr. Muona, who has been keeping me advised on progress. He and a graduate student have been working on a paper concerning the phylogeny of the Dirhagini, to which this species belongs, and have done (or are doing) DNA sequencing of this species toward that end. Muona is also doing a description of the larval stages of this species from the material I supplied him.

I will certainly send you larvae as you have requested, but seeing the great overlap in work and mindful that two heads are better than one, the more collaborative your respective efforts the better I should think. You might even consider joint publication. I have found Jyrki very helpful and easy to work with.

 
Hi Jim
Thank you. I was actually considering co-author with him on the description of this new species. I may also have another one from Arkansas, but will await for Dr. Muona to return to his office on monday for his thoughts on it. A fax illustrating the two unknown eucnemids are still at his office. I have a colleague who has done an excellent illustration for me in the past when I co-authored with Dr. Young on the larval description of Schizophilus subrufus. I'll have to track her down and have her illustrate this new species.

 
I'll need an address
to send larvae to. You can email that privately to me if you wish. Just click on my name, which takes you to my profile page, and find my email address there.

Tribe Dirhagini
Upon viewing adult images, Dr. Muona writes:

"My first instinct was ok, Dirhagini. A bit surprising is the fact that it appears to be Dirrhagofarsus lewisi, although the larvae are not by any means identical with the ones I have seen and are described in the article in Coleopterist’s Bulletin. Of course, it does have several larval forms, so…

"Please send me a specimen, I am especially interested in the male, which should have longer antennae. I think the first one was one."

Not Nem*atodes pen*etrans
Now, upon seeing images of the pupae, Dr. Muona says these are not the species he thought based on larval characteristics. We await adults now before he attempts any further IDs :-)

Moved

Moved

likely Nemat*odes penetr*ans
From Jyrki Muona, Jan 28, 2007:

Jim,

They had arrived last week - really fast! Now that I had the larvae at hand, the situation changes. Somehow one just misses things when looking at images only. First, this is not a described one [meaning larva]. Second, combining the t-formed rods on the prothorax, the few lateral teeth on the head, the pointed spiracular collars and the peculiar last segment makes them characteristic. The similarity to an undescribed Nematodes I bred from Viti Levu are striking and I am fairly sure this is Nematod*es p*enetrans, which, as far as I know is not recorded from NH [not so], but is from Maine and about all the surrounding regions. What makes this tricky is that all Nematodes actually have three different larval forms. The first minute larva is "Melasis-like", soft with large manibles, the second one like yours and the third, prepupal one, entirely different again, poorly sclerotized etc. One thing that makes me wonder is that often Nematodes breed in fairly hard-appearing wood, although at the time the larvae are bigger, the wood usually is soft already.
Please, try to breed it or put a window-trap close by. It would be nice to find out. After all, there are several undescibed "larval genera" you could have, e.g. Sarpedon, Epiphanis etc.
s.
Jyrki Muona

(Asterisks inserted by Jim McClarin to thwart searches on those words yeilding this image.)

Dr. Muona says
he suspects these are larval Micro*rhagus subsin*uatus, which would be a new species for New Hampshire. However, I am shipping him some larvae from this batch in a vial of alcohol so he can make a better determination. Meanwhile I hope that at least some of these will mature so I can add adult images.