Xylomycophagy in a close relative of termites: Lamproblattidae (Blattodea) systematics, ecology, and diet

Abstract

Recent systematic work has shown that Lamproblattidae may be an ancient lineage of Blattodea. Given their putative position as sister to Xylophagodea, investigations of their little-known biology can uniquely offer new insight into the evolution of wood-feeding and thus, the evolutionary precursors to eusociality. Here, we compiled all literature information on Lamproblattidae in a new appraisal, integrating it with novel data collection.

First, we revised the systematics of Lamproblattidae. We provide a key to the family and related taxa, give revised definitions of taxa, remove Eurycanthablatta from Lamproblattidae, describe Lamproblatta mimadelfi sp. nov., and provide a morphology-based phylogeny for Lamproblattidae. The phylogeny weakly demonstrates the monophyly of Lamproblattidae, the paraphyly of Lamproblatta relative to Lamproglandifera, the lack of support for Eurycanthablatta within Kittrickea, and weak support for Anaplecta + Lamproblattidae.

Next, we reviewed hundreds of iNaturalist observations to gain new occurrence data for Lamproblattidae. Combining this distribution data with that from a literature review and other publicly available databases, we model the habitat suitability for Lamproblattidae. Finally, we used multiple genetic techniques to reveal new information about the physiology of L. mimadelfi.

We find no evidence for the presence of hindgut parabasalians, but we do find evidence of indirect wood-feeding – xylomycophagy. Metabarcoding of gut contents shows that L. mimadelfi is a generalist feeder, but wood-associated fungi are the most consistent and abundant food across samples, comprising about 40 % of its diet. We then discuss all the results to hypothesize possible evolutionary sequences for the acquisition of direct wood-feeding in Kittrickea, and the shift from generalist to specialist feeding.