Behavioral homologies are recognized in leptocerine caddisflies (Trichoptera) even though endproduct morphology is different

Leptocerid caddisflies have a wide variety of case forms, and therefore it might seem difficult to establish behavioral homologies at the family or generic levels. We videotaped case building in representatives of 9 genera in 8 leptocerid tribes and compared their behavior to 32 other caddisfly genera in 11 families to determine if family-specific behaviors could be identified. We also constructed a behavioral phylogeny of the 8 leptocerine genera and compared this phylogeny to an existing morphological phylogeny. Four unreversed and 1 reversed behavioral synapomorphies supported the monophyly of the Leptoceridae even though case shape varies among the genera. An analysis of 9 intergeneric behavioral characters produced 1 most parsimonious tree (length 11; consistency index: 1.00; retention index: 1.00) that differed from the morphological phylogeny in the placement of 2 genera. Six character states were homologous relative to the morphological data, 5 of which supported 2 nodes that were previously only weakly supported by morphological data alone. The remaining states were homoplastic relative to the morphological data. In general, detailed descriptions of behavior can yield valuable genealogical information even when behaviors appear superficially different.