[HELICONIUS] Ithoimiinae or Ithomiini? Election fever!

[James Mallet]

Dear All,

The election for the most powerful nation on 
earth is now underway. Another poll was for some 
strange reason not so well reported, even though it has also just taken place.

Keith Willmott just conducted a straw poll among 
friends and ithomiine specialists concerning the 
rank of the name to be used for the ithomiines: 
Subfamily? Or Tribe? The particular ithomiines he 
was referring to consist of the American 
ithomiine species including Tithorea, Melinaea, Scada and others.

I am providing a resume of the conversation for 
your interest, so feel free to comment on this 
list (or privately) if you have strong feelings about the matter.  Jim

_____

The original list contacted were:

(Keith Willmott)
Niklas Wahlberg
Andrew Brower
Jim Mallet
Dick Vane-Wright
Gerardo Lamas
Chris Jiggins
Marianne Elias
André Victor Lucci Freitas
& Mathieu Joron
_____

Here was his original query:

Hi all you ithomiinologos,

Marianne suggests (and I agree) that it's about 
time we tried to come to some consensus whether 
we should call ithomiines Ithomiinae or 
Ithomiini. Obviously it won't be a solution that 
pleases us all. I'm going to try to give reasons 
for each option, and being in the Ithomiinae camp 
I'm obviously biased in that direction and will 
add my own comments why I think arguments for 
Ithomiini are weaker, so I'm expecting the 
ithomiinists to reply and even the score. If we 
can't ultimately come to an amicable decision, maybe we should take a vote...

For Ithomiini:

Ackery et al (1999) proposed downgrading 
Ithomiinae to Ithomiini on the sole basis that 
ithomiines, danaines and tellervines form a 
monophyletic group. However, there is no link 
between monophyly and taxonomic rank so this is 
not an argument one way or another. It may also 
be (though I'm guessing, and have no evidence) 
that phylogenetic distance between ithomiines and 
danaines is comparable to that between other 
tribes, not subfamilies. However, if one were to 
apply such a criterion (that taxa of the same 
rank should be separated by a similar distance, 
or have a similar molecular-clock date of origin) 
to classification across all organisms at all 
taxonomic ranks, I imagine the result would be 
taxonomic chaos. The suggestion by barcoders that 
a fixed barcode distance should be used to 
delimit species taxa is analagous and I imagine 
doesn't have many followers among you people.

For Ithomiinae:

Ecologically (hostplants, habitats, behaviour) 
and evolutionarily (evolving largely on different 
continents) danaines and ithomiines are very 
distinct, linked only by use of PAs in sex 
pheromones and/or for defence. While ithomiinists 
might argue that the differences between 
ithomiines and danaines are fewer than between 
other nymphalid subfamilies, this is difficult to 
demonstrate given that most other nymphalid 
subfamilies are so heterogeneous it's hard to 
characterise them. I don't think that the 
morphological and ecological differences among 
Ithomiinae tribes are any less significant than 
they are among tribes in, say, the Biblidinae, 
Satyrinae or Charaxinae. Ultimately, I think the 
most important consideration is what is to be 
gained by changing a classification that has 
served very well for the last 50 years in 
countless publications on systematics, ecology 
and evolution, not only on ithomiines, but also 
on danaines, and has recently appeared in the 
first comprehensive neotropical checklist? 
Although Danainae would continue to exist, its 
new meaning would be very different from before. 
Avoiding unnecessary confusion in nomenclatural 
changes is one of the main responsibilities of 
taxonomists. As far as I can see, all that is 
gained is the representation of monophyly among 
the groups, something we all know anyway.

But I await your opinions, and please circulate 
to others whom I may have inadvertently omitted from the mailing list.

Keith
_____

Andy Brower then summed up the opposition to the motion:

Hi all,

There are certainly reasonable arguments on both 
sides here, but I agree with Niklas, for several 
reasons.  First, the selfish one:  we called them 
Ithomiini in Brower et al. (2006), with 
justification mainly based on the monophyly of 
Danaini+Ithomiini+Tellervini  argument.  This 
raises the second, more important point:  if 
Ithominae is viewed as a subfamily, then 
Tellervinae (5 or 6 species) and Danainae s.s. 
(~150 species) should be viewed the same way.  As 
noted by Jim and others, this has parallels in 
Heliconiinae, which as currently construed 
contains former "families" "Acraeidae" and 
"Argynnidae," that each represent quite diverse 
monophyletic groups and could easily be 
recognized as distinct subfamilies.   And so, too 
with Satyrinae, currently circumscribed to 
include former subfamilies Morphinae, Brassolinae 
and Amathusiinae.  To me, having a nomenclature 
for Nymphalidae with fewer, more inclusive 
monophyletic subfamilies yields a classification 
that better reflects our understanding of the 
cladistic structure of the group than one with many taxa at the same rank.

Note that the other two "big" families 
(Lycaenidae and Hesperiidae) each have seven 
subfamilies in their current circumscriptions, 
while Nymphalidae under the fewer-more-inclusive- 
scheme will have 12 (Libytheinae, Danainae, 
Heliconiinae, Limenitidinae, Nymphalinae, 
Apaturinae, Biblidinae, Cyrestinae, 
Pseudergolinae, Satyrinae, Charaxinae, Calinaginae).

I would also note that within Ithomiini/ae, there 
is at present only one subordinate rank employed 
between the group as a whole and the genera, so 
there is not a problem with the squeezing out of 
a group of subtribal names (as there is in 
Danainae s. s. if it is reduced to a tribe).

cheers,

Andy
_____

And here was Keith's summary of the voting, and his personal decision:

Hi all,
Everyone seems to have had their say, votes are: 
Ithomiinae 4 (Keith, Andre, Gerardo, and, just 
about, Mathieu), Ithomiini 3 (Niklas, Chris, 
Andy), and undecided/unconcerned 3 (Jim, Dick, 
Marianne). As Andy said, there are good arguments 
on both sides. Since this vote doesn't tell us 
too much and I and Gerardo both admit we are 
biased, I suggest leaving the matter in the hands 
of Andy, Niklas and Andre, who seem to be writing 
some major paper on nymphalid classification, 
since they see the "bigger picture". I'm sure 
you'll seriously consider all our points and 
whatever you decide, we'll all follow.
Thanks everyone for your thoughts,
Keith
_____

Finally, a rejoinder to a comment by Andy Brower about the decision:

Hi Andy,
Dick suggested something similar, and it might be 
worthwhile. I don't know exactly what you have in 
mind, but feel free to draft something or let me 
know if you want me to. I guess we should also 
have a final result, once you, Niklas and Andre have finished deliberating...
Keith
>Hi all,
>
>I was wondering if anyone thinks it would be 
>appropriate to compile our messages back and 
>forth as a sort of conversation paper that we 
>might send to the News of the Lep Soc or Antenna 
>or someplace.  It seems like an interesting 
>illustration of how nomenclature (the "old-fashioned kind) works.
>
>cheers,
>
>Andy








________________________________

James Mallet
UCL
www.ucl.ac.uk/taxome/jim
2008-2009 Fellow, Wissenschaftskolleg zu Berlin
Wallotstrasse 19
14193 BERLIN
Germany

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