Troutnut.com Fly Fishing for Trout Home
User Password
or register.
Scientific name search:

> > Maccaffertium vicarium / rivulicolum

Brookyman has attached these 6 pictures to aid in identification. The message is below.
View Full SizeView Full Size (4X larger)
View Full SizeView Full Size (3.3X larger)
View Full SizeView Full Size (3.9X larger)
View Full SizeView Full Size (2.4X larger)
View Full SizeView Full Size (1.6X larger)
View Full SizeView Full Size (2.5X larger)
BrookymanFebruary 20th, 2013, 1:40 am
Banned
Posts: 797
This is the real odd duck in the pond. Likely a March Brown.

I found him tonight in my Maccaffertium vicarium / rivulicolum file.

The absents of tergal markings past each transverse bands is weird. Meaning only having the black bands on each abdominal segment and not much other coloring. At first I thought the color must be coming in still from a recent molting.

I am not so sure of that. The wing pads shape and color are way more
developed than the topside of the abdomen. It looks like it has lateral
projections on segments 3-9, and very pale cream colored gills.

What I find intriguing and odd is the freckles all over the ventral side the abdomen.

I do not have the sample but I think is most likely 11 mm the same as
the other M vicarium / rivulicolum samples I collected that have similar ventral markings but no freckles.

I look forward to the input on this guy

Mack.
Banned for threatening another user and then trying to circumvent a kinder "soft" ban with fake accounts
EntomanFebruary 20th, 2013, 2:21 pm
Site Editor
Northern CA & ID

Posts: 2604
Mack -

It seems that every other vicarium I look at is uniquely marked in some fashion or another. You're right that this is a plain one though, legs as well as terga. I don't think it has anything to do with molting as the thoracic dorsum is usually the last to darken. Based upon the maculation of the 9th sternum you could say it looks in between the old fuscum description and what was once considered necessary to be vicarium. But that can be said for many specimens. It was known at the time (or at least suspected) that the two were proving to be highly variable and Rivulicolum was a species name given to those that approximated an arbitrarily selected midway point between the two extremes. Keep in mind this was based solely on subtle differences in the maculation of a single sterna (in the nymphal stage). It seems absurd, in hindsight. It was later discovered that when nymphs belonging to this "middle" species were reared, the resultant adults often keyed to either fuscum or invaria. There was even a well documented study complete with photographic examples of these three (the author escapes me off the top of my head) showing the incredible amount of gradations between them; proving the practical impossibility of knowing where one ends and the next begins. Burkes reasoning back in the 50's questioning the validity of the rivulicolum concept and designating it a junior synonym of fuscum probably reinvigorated the process of sorting the mess out.

The brief discussion at the end of the vicarium section in Bednarik & McCafferty '79 explains all this better than I can and is worth the read. The last paragraph in the "Use of Color" section earlier in the paper (where intraspecific variability in maculation is discussed as well) should also be helpful.
"It's not that I find fishing so important, it's just that I find all other endeavors of Man equally unimportant... And not nearly as much fun!" Robert Traver, Anatomy of a Fisherman
BrookymanFebruary 21st, 2013, 9:34 pm
Banned
Posts: 797
Just stating I had previously posted to this and was very wrong in my statement.

I had confused two different species so I deleted it.

Sorry for that.

Mack.
Banned for threatening another user and then trying to circumvent a kinder "soft" ban with fake accounts
EntomanFebruary 21st, 2013, 11:32 pm
Site Editor
Northern CA & ID

Posts: 2604
No problem, Mack. That happens to all of us from time to time. I've deleted some real doozies of mine in the past (hopefully before too many saw them).:) I was wondering where you were going with that post, but was waiting for your follow up before I responded. Now I don't have to...:)

BTW - You don't need to go to all the trouble of providing links to the papers. Mention of the author(s) and year is all that's necessary and even then only if you are quoting them directly or mentioning their use as a source.
"It's not that I find fishing so important, it's just that I find all other endeavors of Man equally unimportant... And not nearly as much fun!" Robert Traver, Anatomy of a Fisherman
BrookymanFebruary 21st, 2013, 11:36 pm
Banned
Posts: 797
Thanks Kurt. Now I have beer and should not type LOL :)

Mack.
Banned for threatening another user and then trying to circumvent a kinder "soft" ban with fake accounts

Quick Reply

You have to be logged in to post on the forum. It's this easy:
Username:          Email:

Password:    Confirm Password:

I am at least 13 years old and agree to the rules.

Related Discussions

TitleRepliesLast Reply
Re: Size Variation in March Browns
In the Identify This! Board by Fishskicano
5May 20, 2009
by GONZO
Re: Maccaffertium vicarium... "March Brown" ...nymph
(4 more)

In the Identify This! Board by Brookyman
4Jan 31, 2013
by Brookyman
Re: Agnetina
In Agnetina capitata Stonefly Nymph by GONZO
2May 8, 2007
by Troutnut
Re: I think it in the Mac group ???
In the Identify This! Board by Brookyman
14Jun 21, 2012
by Brookyman
Re: Insect photos on CatskillFlies website
In the Mayfly Genus Ephemerella by Jpsully
4May 24, 2008
by Softhackle
Re: Taxonomic ( synonym ) question.
In General Discussion by Brookyman
13Jun 6, 2013
by Brookyman
Acroneuria specimen moved from genus to species level
In Acroneuria carolinensis Stonefly Nymph by Entoman
0
Re: Allright guys...what is it?
In the Identify This! Board by Catskilljon
19May 27, 2009
by GONZO
Re: maccafertium?
In the Identify This! Board by Dryfly
17Jun 2, 2007
by Dryfly
Re: Green Drake QUig Cripple
In Fly Tying by JOHNW
2May 15, 2011
by JOHNW
Most Recent Posts
Re: Question about sulphurs in PA
In General Discussion by Lam (RleeP replied)
Re: Euro Nymph Rod
In Gear Talk by Wbranch (Partsman replied)
Re: Grannoms!
In Fishing Reports by Martinlf (Partsman replied)
Re: To Many Flys
In General Discussion by Flytyerinpa (Jmd123 replied)
Re: Does indicator affect leader size?
In Fly Tying by Gt2003 (Adirman replied)
Re: Spring Steelhead
In Fishing Reports by Wbranch
Re: Luther, MI
In General Discussion by Wiflyfisher
Re: It's On
In Fishing Reports by Martinlf (Summer_doug replied)
Re: Eastern Sierras 2019
In Fishing Reports by Summer_doug
Re: Greetings from Colorado
In General Discussion by Gripngrin (Iasgair replied)