Biology of Eukiefferiella endobryonia sp. nov. A a colony of Fontinalis dalecarlica growing on the sides of pebbles in a gently flowing inlet connected to Mountain Lake, VA, USA (type locality) B a colony of Fontinalis novae-angliae occurring in a rapidly flowing stream at Sparks Lane, TN, USA C early fourth-instar larva, undulating its body in the tube D immature capsule of Fontinalis dalecarlica attached to the stem underwater E fourth-instar larva F fourth-instar larva feeding on a leaf margin of F. dalecarlica G a tube structure of the third-instar larva, which was mainly built from particles from the feces of mature larvae H amorphous, jelly-like silk mass spotted with detritus and diatoms, ripped off of the inner wall of the inner end of the pupal case I a dissected leaf-rolling case, consisting of five leaves and the resident pupa; the leaves used as the case materials are placed in the order of leaf arrangement, with the outermost leaf at the left-most; the innermost leaf (right next to the pupa) contains the head capsule (white arrow) and exuvium of the fourth-instar larva; some debris (pink arrow) and silk mass (black arrow) stuffed in at both ends can be seen J a pupa in its case: the pupal head is oriented toward the distal end of the shoot tip; most of the leaves near the pupal case were consumed by the larva early in the fourth instar stage.