Alloecentrella magnicornis is a species of caddisfly belonging to the order Trichoptera.

[3] The holotype of the species was originally collected in the Waitākere Township area in 1934, and is housed in the Auckland War Memorial Museum.

[5] Phylogenetic analysis indicates that Alloecentrella magnicornis forms a clade with Pycnocentrella eurensis, and is more distantly related to Pycnocentria species, Beraeoptera roria, Confluens hamiltoni, Pycnocentrodes aureolus and species of Olinga.

First joint slightly longer than head with moderately long fuscous and fulvous hairs.

[8] Alloecentrella magnicornis is often found in swift-flowing streams in the upper North Island, typically in forested areas where rock substrates allow liverworts and mosses to grow.