Record Details
Field | Value |
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Title | The taxonomic significance of the male genitalia and associated structures in the genus Eucerceris cresson (Hymenoptera : Sphecidae) |
Names |
Davidson, Jerry Mitchell
(creator) Ritcher, Paul O. (advisor) |
Date Issued | 1970-04-27 (iso8601) |
Note | Graduation date: 1970 |
Abstract | The male genitalia of 69 species, representing eight genera of sphecid wasps, were examined in order to ascertain their taxonomic value. In all, the male genitalia of approximately 1000 specimens were critically studied. Emphasis was placed on the genitalia and associated sclerites of the known males in the genus Eucerceris. The genitalia of most species are so different that they can be defined by this structure alone. The pygidia, and to a lesser extent the seventh and eighth sterna, also offer reliable characteristics with which to distinguish species. The North American genera of the subfamily Philanthinae can be differentiated on the basis of male genitalic morphology. The morphology of the male genitalia of Eucerceris indicates a close relationship with Cerceris. This relationship is also indicated by external non-genitalic morphology. The genitalia of Didesmus males are radically different from those of Cerceris and Eucerceris but nevertheless, Didesmus is most closely related to these genera on the basis of non-genitalic characters, The male genitalia of the philanthine genera Aphilanthops, Clypeadon and Listropygia are very similar but differ considerably from those of the cercerine genera Cerceris, Eucerceris and Didesmus. These differences and similarities support the presently accepted classification and placement of these genera. Based on genitalic characters, Philanthus and Trachypus appear to be closely related to each other. On the basis of external non-genitalic characters, however, these genera appear to be only distantly related. Without examining other genera from Africa, Asia and South America, determination of the relationships of Philanthus and Trachypus to other groups is not possible. A key to the genera and a key to the species of Eucerceris based on male genitalia are provided. In addition, the genital structures of 33 species of Eucerceris are described in detail and the major key characteristics illustrated. |
Genre | Thesis/Dissertation |
Topic | Wasps |
Identifier | http://hdl.handle.net/1957/46203 |