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3. Help to get some specimens of the isopod Caecidotea communis

My name is Leonardo García, I am a biologist intern in the National Autonomous University of Mexico and I'm doing my thesis with title "Morphological variation in the genus Caecidotea isopods (Packard, 1871) (Crustacea: Peracarida: Isopoda) of Mexico." Inside the National Collection of Crustacean, Biology Institute (UNAM).

I was wondering if somebody can help me to get some specimens of the specie Caecidotea communis and send them to me to continue with my thesis work. It would help and enrich my study.

Thanks for your attention

Leo

Hi Leo-

I assume you are pursuing an advanced degree in marine biology, as I believe Caecidotea communis to be a marine isopod. As far as I know, folks on this forum would be more likely to be familiar with freshwater isopods.

Maybe I'm missing something here, but wouldn't it have been prudent to made sure you had an adequate source of the critters you were intending to study before embarking on the study? :-)

Rodger, Caecidotea communis is a freshwater isopod. We have it here in PA. Or maybe I'm missing something here...;)

Hi Eric,

Ah, I stand corrected. Thanks for pointing out the error regarding my belief. :-)

Leo said I had some of them on my site and asked if I could get him any more from Wisconsin, but since I'm in Alaska I pointed him here to see if anyone else could help.

Leo, if there are photos of that species on this site, can you post a link to their specimen pages so people can see what they're looking for? A description of the identifying characteristics of that species would be helpful, too.

Eric -

This one had me going as well. I've only seen the family name Asellidae when these critters are mentioned in FF literature. I've never run into them in my angling. Is Caecidotea communis the species name of your most common Cress Bug? Do they fill the niche in your SC weedbeds that Gammarus scuds do out here? Are they as photophobic? The only things I know are that they can be abundant in PA, are scavengers, and that they are worth imitating as the fish seem to relish them. Our hatch page on this critter is blank and I'd like to add any info you can provide.

Thanks,

Ah, we were thinking the same thing, Jason. I moved the topic to the hatch page. My hunch is the PA contingent will be able to help Leo.:)

Honestly I don't have a species key so I can't tell you if what we have is communis. If it is. How many pounds do you want Leo? ;)

:)LOL

Thanks for the welcome! =)

Hi all!

I'll be happy to provide taxonomic information as well as the biology of the freshwater isopod.
I have some identification keys that are very basic to clearly distinguish them with the help of a pair of microscopes.
I attached a link where you can see the key to Williams (1970) A revision of North American epigean species of Asellus. On pages 4-17 is the description of the species Caecidotea communis (most common in North America). I recommend paying attention to pages 8 and 11 as the palm of the second pleopod gnatopod are heavier characters in taxonomic identification.

This is the link to download the key
http://si-pddr.si.edu/jspui/bitstream/10088/5397/2/SCtZ-0049-Lo_res.pdf

To differentiate between males and females is easy. Pay attention to the palms of the gnatopod, it´s presence is a sexual dimorphism in males. Because this gnatopod is much larger in males (Figure A on page 8, first pereiopod).

Crepuscular, it would very kind of you could help me. I just need at least 20 specimens. Would it be possible to send me these specimens?

Thank you all!