Dactylella, a genus of 30 species of fungi in the order Helotiales (phylum Ascomycota, kingdom Fungi) that exists as asexual forms (anamorphs) and captures and kills nematodes (roundworms). Once prey is captured, a penetration tube grows out of a hypha (one of the filaments that make up the body of a typical fungus) and enters the body of the prey. The hypha then begins to grow and branch, forming haustoria (special absorbing structures). Enzymes secreted by the fungus kill the nematode.