Bridging ecology and systematics: 25 years of study of larval morphology of world Dytiscidae

Abstract

Although the Dytiscidae are among the most common insect inhabitants of freshwaters, knowledge of their larval morphology is scant throughout the world. The identification of larvae is a continuing problem because the literature available to accomplish this is scattered, limited to certain groups, outdated, difficult to use, or non-existent. Recent studies have demonstrated the taxonomic and phylogenetic value of chaetotaxy in studying larval Dytiscidae. Study of body sensilla (setae and pores) were shown to be useful and important both for diagnosis and study of phylogenetic relationships among taxa. The fact that all these studies were conducted separately over a period of more or less 25 years does not however facilitate comparison among taxa. This chapter synthesizes these studies into a more comprehensive approach, which should facilitate comparison among the dytiscid subfamilies. A corollary objective of this chapter is to exemplify how knowledge of dytiscid larvae and an ability to identify them has the potential to make the wealth of characters present in the larval stage available for ecological study.