Requests for Help and Information
Below are recent requests for information and/or help received by the webmaster. If you provide help and you feel this information would be of interest to the chironomid community, please notify the webmaster for inclusion on this page. Messages will be listed most recent first.
However, a faster method of communication would be to utilize either the Chironomidae Discussion Forum (web) or the Chiro-L listserver (email subscription).
05 October 2005 - Jon Martin
07 September 2004 - Jake Benner
08 August 2004 - Gerald Bergtrom
11 July 2004 - Ram Porat
Received 05 October 2005 - Jon Martin
I am seeking specimens of all life stages of Einfeldia dissidens from Europe for comparison with Japanese specimens - which are probably a different, but closely related species. In particular I would like at least some specimens preserved in 85% or higher ethanol for molecular analysis.
Jon Martin, Department of Genetics, University of Melbourne, VIC 3010, Australia
I have a question regarding chironomid larval behavior, so I thought I'd drop you a note and maybe (?) you could post it to your list or send it to the members of your group (great website, by the way).
A colleague and I are investigating some trace fossils (burrows, tracks, trails, etc.) left in glacial lake sediments of the Connecticut River Valley (MA, VT, NH, ME), USA. To date, many workers have described various tracks and trails made by invertebrates in these sediments and in other glacial lakes around the world. However, there has been much debate about the origin of one in particular known as Cochlichnus in trace fossil-speak (I know, I know, complain to the ICZN). It is a continuous sinusoidal trail with an amplitude of 1-3 mm and wavelength of 5-10 mm. I have attached a picture of a bedding plane covered with these trails to this email.
Early workers in the 1890s assigned these trails to the activity of chironomid larvae but gave little in the way of evidence. Later workers cited these early studies in their papers as evidence for a chironomid origin. In the 1970s a geologist cited an entomologist who stated unequivocally that these sinusoidal trails can ONLY be made by nematode worms, and NOT by insect larvae. The problem is that this geologist collected mud from a modern trace-in-progress on a flat in Puerto Rico. In that sample there were two organisms present: a nematode and a chironomid larva. In the late 1970s another group of geologists went back to the early literature and since it had been "debunked" a few years earlier said these trails must represent the activity of some other insect larvae. Personal communication in the mid 1980s by my colleague with some "experts" at (name withheld) University claimed to "not know much about nematodes...(but) Dipterid fly larvae DO NOT produce sinusoidal trails and ONLY irregularly and vertically burrow the sediment." (emphasis added). Finally, in the late 1980s a geologist, Robert Metz, made a collection of a sinusoidal trace-in-progress at the edge of a pond in New Jersey. From this sediment sample he extracted only one macroinvertebrate: a chironomid larva.
So...which is it? Can aquatic chironomid larvae make sinusoidal trails in the process of feeding in fine-grained sediment? Is there a physiological restriction that would inhibit them from behaving in that way? Even better, have you ever observed this behavior in situ?
We appreciate any help that you can offer, and you will be properly and gratefully acknowledged for your assistance
Jake Benner
Note: The webmaster frequently receives requests regarding chironomid breeding colonies. If you are currently maintaining a breeding colony of midges or know of researchers and/or institutions that have these, and would be willing to share this information, please let the webmaster know so that I can develop a "breeding midge colony directory" web page. Further, there is a new page regarding sources for chironomid cultures (see menu left).
Dear Chironomid Worker:
If you currently collect chironomids from nature, or if you are maintaining a breeding colony of chironomids in your laboratory, we respectfully ask for your assistance in obtaining larvae. My graduate students and I have been studying the structure, organization, expression and evolution of chironomid hemoglobin genes for some time (e.g., Gruhl et al., 1997; Kao et al., 1995a, b; Trewitt et al., 1995), and we are starting comparative study of the structure of globin genes and globin gene clusters in geographically separated populations and species of Chironomus. This will require obtaining larvae of known chironomid species from around the world. DNA would be extracted from the larvae and subjected to molecular cloning and/or PCR (polymerase chain reaction) amplification of specific globin genes or gene regions. Globin genes and adjacent DNA isolated in this manner would be sequenced and the sequences would be analyzed with phylogenetic tools to trace the evolution of individual genes and gene clusters. With your assistance in providing larvae, the genomic libraries we plan to make could be used for many other studies. The libraries that we create would be made available to you for your own purposes (this could include collaboration on molecular systematic studies, which we are also planning).
Because of your reputation in the field of Chironomus biology, we respectfully request your help in obtaining larvae from your laboratory and your part of the world. We are interested in as many different species as you can send us, including some that inhabit unusual environments (for example, salt-water species such as C. salinarius), and species of Chironominae that do not contain hemoglobin (for example Proteamesa olivaceae). Because we have studied C. thummi (riparius) and C. tentans extensively, we are also interested in different populations of these species. Your assistance to us will of course be gratefully acknowledged in any publications arising out of this work.
If you are able to help us, please respond by e-mail to bergtrom@csd.uwm.edu. We will then send you a description of how we have used silica gel and salt (NaCl) to preserve larvae (because these methods do not require refrigeration, they are effective and permit inexpensive shipping of samples). Please accept our sincere gratitude in advance.
Gerald Bergtrom, Ph.D., Professor of Biological Science
Some references:
- Gruhl, M.C., Kao, W-Y and Bergtrom, G. (1997) Evolution of orthologous intronless and intron-bearing globin genes in two insect species J. Mol. Evol. 45, 499-508.
- Kao W-Y, Bergtrom G (1995) Sequence of globin 6 gene alleles and linkage of globin 6 and 7B genes in the insect Chironomus thummi thummi. Gene 153: 209-213
- Kao W-Y, Hankeln T, Schmidt ER, Bergtrom G (1995) Sequence and evolution of the gene for the monomeric globin I and its linkage to genes coding for dimeric globins in the insect Chironomus thummi. J Mol Evol 40:354-361
- Trewitt PM, Luhm RA, Samad F, Ramakrishnan S, Kao W-Y, Bergtrom G. (1995) Molecular Evolutionary analysis of the YWVZ/7B globin gene cluster of the insect Chironomus thummi. J Mol Evol 41:313-328
Mail/Ship To:
Dr. Gerald Bergtrom, Ph.D.
Biological Sciences Dept.
University of Wisconsin-Milwaukee
P.O. Box 413 3209,
North Maryland Avenue
Milwaukee, WI 53201
I am looking for any information on the following subjects:
1) Infestation of chironimid larvae through rapid filtration systems.
2) Use of sprinklers in filtration ponds to prevent egg-laying by adult chironomids.
3) Any other methods which prevent egg-laying by chironimids in filtration ponds, reservoirs and holding tanks.
4) Anti-fouling paints that are approved by the health administration for use in potable water systems.
5) Affectivity of approved anti-fouling paints in preventing settling of chironimids in storage tanks.
Dr Ram Porat,
Chief Biologist,
Mekorot National Water Company
Email: rporat@mekorot.co.il
Page last reviewed: Thursday, 06-Oct-2005
