The question of how many, and which stephanid taxa to include in the analysis is also a complex decision. Stephanids have a peculiar general structure, which makes them very difficult to interpret: their general morphology and structure are highly uniform throughout the family, but the intra- and interespecific variation of subtle characters is enormous.
Due to the first problem, i.e., the extremely high general morphological uniformity, it is very difficult to understand the natural "groups" in Stephanidae. For example, by the end of my Master's degree thesis, I was convinced that two North American species were somehow related to the Australian species of Parastephanellus, since they shared almost every important character I knew by them. It was only after a very arduous work with the Australian species that I could finaly detect the synapomorphies for the genus Parastephanellus, and securely isolate it from the North American species. Also, it was only after this study that I was able to notice that the Australian species of Parastephanellus form a "unit" within this genus, which is different, for example, from the New Guinean species and the New Caledonian species of the same genus. Thus, the decision to use representatives from these three "subgroups" of Parastephanellus could only be made after a lengthy and difficult revision.
To simply include "as many species as possible", or "all that look somewhat different", is not a good idea, because the high variability of subtle characters makes nearly every stephanid specimen an unique morph. It seems more accurate to work with species from distinct biogeographical regions first. They must be carefully examined, and well understood, and only them a trully representative set of species can be chosen.
As outgroups, I will be considering representatives of the following families.
About half of the current stephanid genera in the literature seems to be clearly monophyletic, but the limits of many other groups are still unclear. These are:
Megischus Brulle. This group is currently defined by "not having" the characters of other Stephaninae genera. The definition of its status (mono-, para- or polyphyletic) will have to wait for the cladistic analysis.
Parastephanellus Enderlein. Although distinclty delimited, it is intermediate between the Stephaninae and the Foenatopinae. Its relationships and origin is still totally unsuspected.
Madegafoenus Benoit. I am still trying to borrow representatives of this genus. This was the last genus described for Stephanidae, and is based on a very heterogeneous set of species.
Foenatopinae. This is a very speciose group, with 140 species worldwide. Because Foenatopinae taxa show weak differences between them, nearly every taxonomic treatment could be justified for this group, from synonymyzing all its three constituent genera, to splitting each of them in biogeographical subunits. The phylogenetic treatment of this group is perhaps the only tool to keep it free of the creation of arbitrary classifications.
HOW YOU CAN HELP
1. Megalyrids! These rare wasps are very important in my analysis, and I would highly appreciate a loan of any specimen you may have.
2. Specimens from Madagascar. The problem-genus Madegafoenus is from there, as are many other rare stephanid species I need to examine. Any Madagascarian specimen will be of great help!
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This page last updated: March 09, 1998.