A Character Analysis of the North American Potter Wasps (Hymenoptera: Vespidae; Eumeninae)
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See discussions, stats, and author profiles for this publication at: https://www.researchgate.net/publication/247509646 A character analysis of the North American potter wasps (Hymenoptera: Vespidae; Eumeninae) Article in Journal of Natural History · October 1985 DOI: 10.1080/00222938500770551 CITATIONS READS 91 446 2 authors: James Michael Carpenter Jeffrey Cumming American Museum of Natural History Agriculture and Agri-Food Canada 301 PUBLICATIONS 10,736 CITATIONS 112 PUBLICATIONS 1,695 CITATIONS SEE PROFILE SEE PROFILE Some of the authors of this publication are also working on these related projects: Taxonomy View project Vespidae View project All content following this page was uploaded by James Michael Carpenter on 21 May 2014. The user has requested enhancement of the downloaded file. JOURNAL OF NATURAL HISTORY, 1985, 19:877 916 A character analysis of the North American potter wasps (Hymenoptera: Vespidae; Eumeninae) JAMES M. CARPENTER and JEFFREY M. CUMMING Museum of Comparative Zoology, Harvard University, Cambridge, MA 02138 U.S.A. and Department of Entomology, University of Alberta, Edmonton, Alberta T6G 2E3 Canada (Accepted 31 July 1984) A cladistic analysis of the nearctic genera of Eumeninae is presented. The ground plan states of 43 character systems are discussed, and the first comprehensive cladogram for any significant portion of the subfamily is presented. At least eight of the 26 genera are apparently nonmonophyletic: Zethus, Montezumia, Euodynerus, Odynerus, Pterocheilus, Stenodynerus, Leptochilus and Microdynerus. A key to the nearctic genera accompanies the text. Downloaded By: [American Museum of Natural History] At: 18:07 31 October 2007 Introduction The Eumeninae is the primary lineage of the Vespidae. Commonly known as potter wasps, they are an abundant and very diverse group, with greater species richness than the remainder of the family. They are common predators in many ecosystems, and various aspects of their behaviour are of interest to evolutionary biologists (Cowan 1979, 1981, Smith and Alcock 1980). But they are relatively unstudied as either potential biological control agents (Bohart et al. 1982) or as subjects addressing important evolutionary questions (Cowan 1978). These areas of investigation require some knowledge of evolutionary relationships in order to be pursued successfully. Progress in Eumeninae is hindered by their higher classification, which has been termed chaotic (Parker 1966). This paper is the first application of cladistic analysis to the Eumeninae. We invest!gate here the phylogenetic importance of characters used by previous authors, as well as new characters. A primary aim is to establish the ground-plan states of the characters for the subfamily as a whole, as well as the various less inclusive groups. This study treats in detail only the nearctic genera. However, it draws upon a study currently underway on the 'stem-group' of the Eumeninae (Zethinae and Raphiglossinae of authors) by the senior author, and the results of a study on the higher-level phylogenetic relationships of the Vespidae (Carpenter 1981). Also, together we have now seen representatives of nearly all of the world genera of Eumeninae, and refer to some of them in the discussion of character states as appropriate. Thus, the data base is not limited to the nearctic fauna. The results presented here are a framework upon which a comprehensive generic reclassification can be built when the rest of the world genera have been similarly analysed. Therefore, no nomenclatural changes are made here. However, several unnatural (nonmonophyletic) genera are indicated. 878 J.M. Carpenter and J. M. Cumming Taxonomic history The difficulties in generic classification are caused in part by the diversity and morphological complexity of the group, but are also due in large measure to the history of their taxonomy over the past 45 years. Prior to 1938, few genera were recognized in the Eumeninae. Saussure (1852-1858, Vol. 1 of 'l~tudes') recognized 18 genera of 'Eum6niens' (including Gayella), with Odynerus by far the largest. He divided the latter into four subgenera, thus partly following Wesmael (1836), and further partitioned these into 'divisions'. He similarly recognized divisions in some of the other large genera. In Volume 3 of his 'l~tudes' he introduced names for many of these divisions. Dalla Torre (1904) provided names for those that Saussure did not, but this infrasubgeneric classification was otherwise generally ignored by subsequent workers. Saussure (1875: 148) indicated that the difficulty of classifying the species placed in Odynerus resulted: 'first from the multiplicity of the transitions which almost insensibly ally each form with several others.., it results also from the multitude of details of form'. B1/ithgen (1938 a,b) began a trend of splitting and upgrading of subgenera, by dividing the European species of Odynerus into many genera and subgenera. This innovation was at first strongly resisted by other workers in the group. Bohart (1939b:98), referring to B1/ithgen's treatment of Microdynerus and Leptochilus, criticized it for 'overemphasizing species group differences, and the multiplicity of names which he has added tend to confuse rather than simplify the complex eumenine picture'. Bequaert (1939: 58), although not naming Bliithgen ('a German entomolo- gist'), stated: 'Such a procedure, however, not only leaves out the many annectant species, but it fails as a guide to the study of natural relationships.' Thus both these Downloaded By: [American Museum of Natural History] At: 18:07 31 October 2007 authors echoed Saussure (1875). Nevertheless, Bltithgen's approach was ultimately adopted and applied to other faunae, always on a regional basis. Bohart (1948, 1951) upgraded the taxa he treated as subgenera in 1939, and further genera have been added in the Nearctic by Parker (1965), Snelling (1975) and Bohart (1982,1984). Soika criticized Blfithgen as late as 1953, but eventually adopted and extended the trend of splitting even further, expecially in the Palearctic, Ethiopian and Australian Regions. Van der Vecht (1963) continued this in the Oriental Region. The neotropical fauna has been last to receive such attention. Willink (1967) split Hypodynerus and Soika (1978 b) did the same for Eumenes. Studies currently underway by van der Vecht and others will proceed similarly with the neotropical species currently placed in Odynerus and Ancistrocerus. The value of different characters and their role in generic classification has rarely been specifically discussed in the history of eumenine taxonomy. Saussure ('l~tudes' Vol. 1: xxiii~xvii) gave a discourse on the characters he used in his classification, and many of his interpretations have prevailed to the present (of. Saussure with Kurzenko 1980). Bequaert (1918) regarded the existing generic classification as artificial because the major characters used by Saussure were ill defined or variable. Kurzenko (1980) described directions in the evolution of various characters of Eumeninae, however he did not approach this problem analytically nor did he attempt to relate taxa at the generic level. Thus some of his interpretations are unacceptable (as is his cladogram for the traditional subfamilies using the recurrent veins of the forewing and the mandibles as defining features). The trend of extreme splitting has therefore proceeded without review of the basis for it. This historical development has had some positive results. The extreme subdivision has indeed produced many 'more natural and workable groups' from the 'larger categories" (Parker 1966), and many monophyletic groups have thus been formally Nearctic Eumeninae 879 recognized. However, this is far outweighed by the negative effects. The piecemeal nature of the classification has rendered it nearly incomprehensible to all but specialists in the group. Some 200 genus-group names are currently considered valid in the Eumeninae, but catalogues employing this classification exist only for the Palearctic (van der Vecht and Fischer 1972) and Nearctic (Krombein 1979). Both are now out of date. A comprehensive generic key does not exist even for Europe. Those of Soika (1978 a) and Guichard (1980) omit Paravespa and Cephalochilus, and Tobias and Kurzenko (1978) cover only the European U.S.S.R. The situation for other major areas is much worse. Further, the splitting has resulted in many cases ofparaphyly in the form of residues left in the old 'larger categories'. Bequaert's (1939) statement is today as trenchant as when it was made. Whereas criticism of Blfithgen's approach for not using the species-group category (Parker 1966) may ultimately resolve to a difference of opinion between lumpers and splitters, the paraphyletic taxa and lack of any semblance of a phylogenetic arrangement are much more substantive problems. Not only are these serious obstacles to evolutionary understanding of the Eumeninae, they do not permit the establishment of a truly rational, and so accessible, taxonomy. Methods Cladistic analysis can provide the basis for a more rational classification. As a method of character analysis, the phylogenetic approach is the best means of assessing the significance of the characters previous authors have used to separate genera, or in exploratory analysis of new characters. By distinguishing between less general Downloaded By: [American Museum of Natural History] At: 18:07 31 October 2007 (apomorphic) and more general (plesiomorphic) character states, group-defining characters