Systematics, evolution and larval morphology of world hydradephaga (coleoptera)

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Understanding of all life stages of insects is of critical importance to ecological and environmental management.  However, encounters with immature insects are relatively uncommon compared with adults, yet larvae undoubtedly cause more direct injury to crops and other materials valued by human than do adults.  This is true because most feeding is done in the larval stage whereas adults are primarily involved in dispersal and reproduction. My research emphasizes the study of larval morphology of aquatic beetles. Emphasis is placed on these insects because they are abundant, diverse and provide many challenging taxonomic problems.  Although water beetles are among the most common insect inhabitants of freshwaters, knowledge of their larval morphology is scanty throughout the World.  The identification of larvae is usually a regular and continuing problem for many because the literature available to accomplish this is widely scattered, limited to certain groups, outdated, difficult to use or non-existent.  This situation has been an obstacle to ecological work.  Because of this, I developed a framework, that facilitates comparison among species.  My system of analysis focuses on study of body sensilla (setae and pores).  I demonstrated that the characteristics of setae and pores are useful and important both for diagnoses and study of the genealogical (= phylogenetic) relationships among taxa. Study of larval features should allow more comprehensive classifications to be constructed.  Most classifications of groups of insects are based on study of adult stages only.  Subsequent to publication, these classifications are rarely tested or evaluated.  A way to test these preliminary classifications is to study the larval morphology.  Larvae are under differing selection pressures and therefore show quite different features. A long-term goal of my research is to produce a more rigorous and stable classification by combining characters from larvae with other data sets including adult and molecular characters.